Blog

Chemical mixing is a crucial part of agricultural spraying. Regardless of the type of herbicide, fertilizer, or biologic you use, effective mixing requires proper equipment to ensure precision, safety, and minimize waste.

The main tool to add mini-bulk chemicals is typically a 12-volt diaphragm pump and electronic meter. However, what if I told you there was a way to mix all your bulk chemicals without multiple 12-volt pumps? Let’s look at the pros and cons of the different options and explain how you can use one pump and meter for multiple products without recalibration or disconnecting and connecting hoses.

Chemical Mixing With 12-Volt Pump and Meters: The Good and the Bad 

Anyone mixing chemical batches for a sprayer is likely familiar with 12-volt chemical pumps and meters. These are necessary to add products to your sprayer batches either directly or through an inductor cone. These pumps are effective, but they have several drawbacks including maintenance, limited flow, and of course cost. 

This method also limits your efficiency because you must calibrate multiple meters and add product one at a time carefully watching the meter until you have added your desired amount. You must shut off the valve, and pump, and then move on to the next product. There is also the constant handling of the hoses and meters, moving them around as needed, which can get messy. 

More sophisticated systems, such as the Dura Auto Batch System, allow you to inject each product directly, eliminating the need to handle each one. They will even allow you to set the amount of product you want and automatically shut off the pump once that amount has been reached. 

This method definitely works well, and it is much more efficient. However, it does come with added cost and you still have the potential for pump and meter failure due to the nature of handling agrochemicals. 

There are also automated systems to mix your chemicals without 12-volt pumps and meters. These provide the most streamlined option but they are by far the most expensive. The idea of being able to efficiently add chemicals while accurately measuring them without multiple 12-volt pumps and meters is certainly appealing, but how can you accomplish this without spending thousands if not tens of thousands?  

The good news is that with the right transfer pump for the carrier liquid, meter, and inductor setup, this can be done!

Chemical Mixing Setup Without 12-Volt Pumps

How exactly will one pump handle all the chemicals or additives? Instead of a 12-volt pump on each chemical tote, you can use the suction from a Venturi/inductor to pull product from each tote. This is the same type of inductor assembly that you would find under a cone bottom tank. (If you are not familiar with inductor tanks with a venturi, our guide on chemical inductors will get you up to speed.) 

In the following setup, instead of a cone bottom tank, we have a manifold stacked on top of a gear meter that can measure each product accurately. Each product is drawn into the manifold and through the meter, then feeds into your main carrier line into the sprayer or nurse tank. 

Everything is plumbed together allowing you to add each chemical one at a time. You simply open the corresponding ball valve for the product you want to add and watch the flow meter display until the desired volume is reached. Then close the valve, open the rinse valve to flush the system, and reset the meter before moving on to the next product.

There are a couple of important aspects of this setup that make it work: 1) the gear meter handles all the chemicals without the need for recalibration, and 2) suction is needed to pull chemical from each tank. 

The meter is pretty straightforward, you must ensure you are using a meter that can handle the different agrochemical viscosities. For this, an oval gear meter is required. It is the suction aspect that gets a little more tricky. 

There are two distinct ways one can generate the required suction: You can use the suction from your transfer pump (typically a 2 or 3-inch gas-engine driven pump) or you can use suction from an inductor. These two methods can effectively be used to move your bulk chemical but there are key plumbing differences for each one. 

Dultmeier sales offer prebuilt units that work with either method. We will examine those later in this article, but first, let’s walk through the differences between each one and consider the pros and cons of each.

Option #1: Using Suction of Your Transfer Pump

The simpler of the two methods is to use the suction created by your transfer pump. The pump is installed in your main carrier/water line. Each hose from your mini-bulk tanks is plumbed into a manifold. The outlet of the manifold is connected via a “T” fitting into your carrier line. All of the liquid, chemical, and water, is pulled through the pump and into the sprayer or nurse tank.

*Using the suction of a centrifugal pump to pull chemicals from the shuttle/mini-bulk tanks.

Required Components

• 2-inch or 3-inch Engine driven Centrifugal Pump (Preferably a “Wet Seal” Pump)
• Oval Gear Meter
• Flow Meter Display
• Poly “Tee” Fittings for manifold
• Ball Valves
• Hose
• Check valve

Advantages of using suction from your pump

• Lower overall cost
• Simple to setup
• Amount of chemicals you can add is not limited by the volume of the carrier that is pumped

Disadvantages of using suction from the pump

• All the chemical goes through the pump, potentially causing pump damage over time
• Potential to introduce air in the pump or starve the pump of liquid, resulting in seal failure
• Cannot use the pump to provide fresh water for rinse

Option #2: Using Venturi/Inductor System

The second method to draw your chemical into your system with your transfer pump is to utilize a venturi. The pump pushes the water/carrier through the venturi and this creates suction that can pull chemicals from the mini-bulk tanks and into your manifold then through the venturi. In this setup, there is no chemical going through the pump. 

The suction is created by the venturi and the venturi is located on the discharge side of the pump. The pump can also provide rinse water because it is just pumping fresh water and not chemicals. 

This would be a great option if you are already using a cone bottom mixing tank with an inductor venturi manifold on the bottom. You can plumb your chemical manifold into the bottom of your existing inductor cone. This will allow you to use the inductor assembly to suck product out of the cone bottom tank or your chemical manifold. 

*Using suction created from water pumped through inductor assembly to pull chemical from shuttle/mini-bulk tanks.

Required Components

• 2-inch or 3-inch Engine driven Centrifugal Pump (Preferably a “Wet Seal” Pump)
• Inductor System with 2 or 3-inch Venturi Manifold
• Oval Gear Meter
• Flow Meter Display
• Poly “Tee” Fittings for manifold
• Ball Valves
• Hose
• Check valve

Advantages of using inductor assembly for suction:

• Only one pump is needed to create suction and provide rinse
• No chemical through the transfer pump
• No risk of starving the pump

Disadvantages

• More components required means more cost

How to Construct Chemical Mixing Manifold

The central feature of this setup is building your manifold so your transfer pump can be used to pull chemical into the system and meter it accurately. This means we need a “stack” of “tee” fittings on top of a meter with a freshwater line plumbed into the top. It is recommended that a strainer is installed prior to the meter to protect it from debris. 

No matter which of these methods you choose, there are a few key aspects to keep in mind to ensure your system operates effectively. 

Pump Type

First off, the type of pump that you use matters. You can use a two- or three-inch pump. If your main carrier/water line is two inches, then use a two-inch pump. You need a three-inch pump if you want to use a three-inch line. It is important to ensure the pump has adequate horsepower to handle the demands of this application. Typically, this means 5 HP for a 2-inch pump and 9 or more HP for a 3-inch pump. Be sure to contact us if you need help identifying the right pump.

This is especially important if you are using an inductor with venturi. Your pump must meet the flow rate requirements for the inductor assembly to perform adequately. A two-inch pump used with a three-inch venturi assembly will not generate enough flow through the venturi to create the suction needed to pull products out of the cage tank/mini-bulk tank. 

Furthermore, it is recommended that you use a centrifugal transfer pump with a “wet seal”. This type of seal can be run dry for short periods of time without causing any damage to the seal assembly. This is especially significant If you plan to use the suction of the pump to pull product from each tote. You don’t want to risk damaging the pump if a tank runs empty and the pump starts pulling air. 

Plumbing

The hoses from the mini-bulk tanks/shuttles to the inlet of the manifold should be kept as short as possible. The suction of the pump is capable of pulling chemicals from about 20 feet with no problem but there is a limit. It is best practice to limit excess hose length, elbows, and other restrictions as much as possible so the system works efficiently. 

Meter

Using one meter for all of your products requires a meter that does not need to be calibrated for each product and can handle liquids with different viscosities. An oval gear meter is capable of providing consistent measurements of flow rates for both high- and low-viscosity liquids

You can use a meter with a local display to monitor the amount of chemical as it is added. This may be hard see because the meter is located on the bottom of the manifold. GPI offers a meter with a remote display option that can be mounted anywhere that is more convenient to see as you mix your chemicals.

Check Valve

A check valve is necessary to prevent any chemical or carrier flowing back into the manifold. This is installed between the meter and a “Tee” fitting in the main water line. 

Manifold Flange Fittings

Banjo manifold flange fittings are a style of plumbing connection that is much easier to work with than threaded fittings. These fittings are connected via a clamp and a gasket that provides a seal between the two flanges. Using these fittings saves a lot of time in the assembly and disassembly process. A single fitting can be isolated and removed/replaced without the need to unthread an entire group of fittings.

Rinse 

A feature that should not be overlooked. The rinse valve on the top of the manifold/stack ensures that all of the product is flushed out before adding another. The rinse line can be plumbed in a number of ways. The rinse plumbing will vary depending on whether you are using the pump suction or a venturi.

If you are using the suction of the pump (without a venturi/inductor assembly), then you will require a second pump to supply fresh water to rinse out the system.

Prebuilt Chemical Mix Unit: Quick Chem-Mix

Assembling one of these units can be done fairly easily if you have a good idea of how you want to set up your system. However, it does take a bit of time to build and wire the meter and display correctly. This is why Dultmeier offers ready-to-go systems. 

The Dultmeier Quick Chem-Mix system (Part number DUCHEM-MIX) is a complete chemical mixing manifold, meter, and display plumbed together on a stainless steel stand. It can be easily incorporated into your nurse trailer or a stationary mixing location.

There are two separate versions: with inductor assembly and without the inductor assembly. The full unit with venturi inductor (no tank) is ready to go, all you need is to install it on the discharge side of your transfer pump and connect your mini-bulk/shuttle tanks and you are ready to go:

If you want to use it with an existing cone bottom tank and inductor you already have or use the suction of your pump, use the system without the inductor. You just connect the outlet to the inlet of your pump:

Remember that the Quick Chem-Mix units without inductor will require you to plumb a separate freshwater rinse line to the manifold “stack”. 

Quick Chem-Mix Benefits

• Ability to pull chemicals from 20 feet or more depending on your setup
• Meter up to six individual chemicals
• One flowmeter for all products. There is no need to calibrate the meter for each product
• The rinse feature ensures all product is flushed out of the manifold
• Easy to plumb into existing inductor cones with minimal plumbing
• No 12-Volt mini-bulk pumps, just a single transfer pump is needed
• Available with 2 or 3-inch inductor assembly, also available without inductor assembly if you already have a cone bottom tank with inductor
• NEMA-rated weatherproof enclosure protects the display 

More Than One Way to Get the Job Done

There are several effective options for mixing mini-bulk chemicals. The setup you choose depends on your preferences and budget. Whether you assemble it yourself or use the Quick Chem-Mix, this system offers an inexpensive way to conveniently mix multiple products without handling several chemical pumps and hoses. 

If you prefer a more automated system be sure to check out the Dura Auto-Batch System

Air-operated double diaphragm (AODD) pumps are highly versatile, reliable devices widely used across various industries for handling viscous, abrasive, and shear-sensitive fluids. Powered by compressed air, these pumps use two diaphragms in a reciprocating motion to transfer liquid. With no need for electricity, these pumps offer a versatile option for hazardous and demanding environments.

AODDs: Basic Parts and Operation

1. Diaphragms: Located on either side of the pump, the diaphragms are flexible membranes typically made of materials like PTFE or rubber. 
2. Air Chamber: The air chamber (also known as the air valve chamber) is where compressed air is introduced to alternate between the two diaphragms. 
3. Inlet and Outlet Manifolds: The inlet manifold allows the fluid to enter the pump chamber, while the outlet manifold directs the fluid out of the pump after it has been moved by the diaphragms. 
4. Check Valves: Each diaphragm chamber has two check valves, one at the inlet and one at the outlet. These valves are responsible for directing fluid flow in a single direction. Typically a ball and seat style check valve.  
5. Valve Assembly (Air Valve): The air valve assembly, typically located in the center section of the pump, controls the distribution of compressed air to the diaphragms. 
6. Fluid Chambers: Fluid chambers are located on either side of the diaphragms. 
7. Exhaust Port: As compressed air pushes one diaphragm, the air on the opposite side is expelled through the exhaust port. This port vents the air used to move the diaphragms, and in some applications, exhaust air is collected or muffled to reduce noise.
8. Center Section: This is the core of the pump, housing the air valve and the air distribution system. 

How These Parts Work Together

When the pump starts, compressed air is directed into the air chamber behind one of the diaphragms, causing it to push outward and transfer fluid out through the outlet manifold. Simultaneously, the opposite diaphragm is pulled inward, creating suction in its fluid chamber, drawing in new fluid through the inlet manifold. The air valve then alternates the air supply to the other diaphragm, repeating the process. This alternating motion allows AODD pumps to handle viscous, abrasive, and shear-sensitive materials efficiently and reliably.

This design makes AODD pumps ideal for industries where the safe handling of various fluid types—especially in explosive or corrosive environments—is essential. 

Advantages of an AODD Pump

1. Corrosion Resistance

Advantage: Built with materials like PTFE, Viton, and Santoprene, AODD pumps can handle a wide variety of fluids, including those that are abrasive, viscous, corrosive, or contain solids.

Benefit: This versatility allows them to be used in many different industries and applications, from chemical processing to food and beverage production.

2. Self-Priming Capability

Advantage: AODD pumps are self-priming, meaning they can start pumping without needing to be filled with fluid first.

Benefit: This makes them ideal for applications where the fluid source is below the pump or where frequent starts and stops are required.

3. Ability to Run Dry

Advantage: AODD pumps can run dry without damage, unlike many other pump types. This means operating the pump without fluid moving through it.

Benefit: This is valuable in situations where the fluid supply may be inconsistent or may be interrupted. For example, you could use an AODD to pump out the contents of a barrel without needing to monitor the liquid level and shut off the pump immediately when the barrel is emptied to avoid damage to the pump. 

It should be noted that although an AODD pump can run dry, prolonged operation with no fluid can be hard on the diaphragms and other components. 

4. Safety 

Advantage: While not all AODD pumps are inherently explosion-proof, they are powered by compressed air and don’t require electricity, eliminating the risk of sparks.

Benefit: This generally makes them safe for use in hazardous environments where flammable or explosive materials are present, such as in the oil and gas industry. Always be sure to check that your pump and pump materials are compatible and designed for your application and environment.

5. Gentle Pumping Action

Advantage: The reciprocating diaphragm movement in AODD pumps produces a gentle, low-shear pumping action compared to other pump types. 

Benefit: This makes AODD pumps preferable for handling shear-sensitive fluids, such as emulsions, suspensions, and biological materials, without damaging them.

6. Easy Maintenance

Advantage: AODD pumps have relatively simple designs with few moving parts, making them easy to maintain and repair.

Benefit: Maintenance can typically be performed on-site without the need for specialized tools, reducing downtime.

7. Pumping of Solids and Slurries

Advantage: AODD pumps can easily handle fluids containing solids or slurries without clogging.

Benefit: This capability is crucial in industries like wastewater treatment, mining, and construction, where the fluid being pumped often contains particles or debris.

8. Simple Control

Advantage: The flow rate of AODD pumps can be easily adjusted by regulating the inlet air pressure without the need for complex controls.

Benefit: Common air regulators are all that is required to adjust the pump. A simple ball valve can be used to turn the pump on and off.

9. Suction Lift Capability

Advantage: AODD pumps can achieve significant suction lift (30 feet or more!), making them capable of drawing fluid from deep or difficult-to-access locations.

Benefit: This makes them useful in situations where the fluid source is located below the pump, such as in sump pits or underground storage tanks.

Specific AODD Pump Applications Across Industries

The unique design of AODD pumps allows them to fit into several different applications. Let’s examine some specific scenarios where an AODD pump can excel while other transfer pumps fall short.

Safe Transfer of Corrosive and Hazardous Fluids

In the chemical industry, AODD pumps are essential for safely transferring corrosive and hazardous substances. Their seal-less design significantly reduces the risk of leaks, enabling secure handling of acids, solvents, and aggressive chemicals.

Specific applications: AODD pumps with poly body and Teflon diaphragms can be used to pump high concentrations of phosphoric acid and Kynar body pumps with Teflon diaphragms can handle sulfuric acid. 

AODD Pumps in Food and Beverage Production

AODD pumps are widely utilized in the food and beverage sector to handle products like sauces, syrups, and beverages. Their mild pumping action preserves the quality and consistency of materials that can change in viscosity when agitated or stirred (creams, sauces, condiments, etc.).

Specific applications: There are also AODD pumps designed for handling large solids and slurries associated with the meat and poultry processing industries. These pumps are sanitary pumps designed for quick and easy cleaning. Typically featuring high-grade stainless-steel bodies.

Mining and Construction: Heavy-Duty AODD Pumps for Slurry and Dewatering

Mining and construction industries present unique and rugged applications. The need for dewatering dirty water and sludge where the contents and solids sizes are often varied and unpredictable. The right AODD pump can withstand tough environments. They are also portable and can run dry without damage, making them a reliable choice in these demanding fields.

Specific Application: Warren Rupp offers durable pumps with metal bodies (aluminum, cast iron, stainless). The Sandpiper Beast is a tough, clog-resistant pump designed to move fluids with debris up to 2 inches in diameter.

Petroleum Industry

In the oil and gas industry, AODD pumps move crude oil, gasoline, diesel, and other petroleum fluids. The pumps’ lack of electrical components provides explosion-proof safety, making them ideal for hazardous environments. 

AODDs are ideal for handling oils and hydraulic fluids of various weights making them a versatile option for fleet maintenance. 

Specific Applications: The Zeeline NS1040UL is a UL-rated AODD that will safely pump gasoline and diesel fuels up to 37 gallons per minute. 

AODD pumps also work excellent for handling waste oil. 

Car and Fleet Wash

Transferring different soaps, detergents, wax, and sealers requires a pump that can move the fluid without resulting in foaming. It also must handle a wide range of different chemical combinations and viscosities.  

Specific applications: This Yamada poly pump is versatile and has wide chemical compatibility for soaps, detergents, and other cleaning products. 

What Materials are AODD Pumps Made From?

AODD pumps are constructed from a variety of different materials. Different materials are used for the main components: the housing, check valve balls, seats, and diaphragms. 

The housing (or body) of an AODD pump consists of the fluid chambers and inlet/outlet manifolds. Common materials include:

• Aluminum: Lightweight and suitable for oils, coolants, and certain solvents but may corrode with acidic or abrasive fluids.
• Stainless Steel: Durable and resistant to corrosion, making it ideal for food, beverage, pharmaceutical, and certain chemical applications.
• Polypropylene: A cost-effective, lightweight plastic that resists a wide range of chemicals. 
• Kynar (PVDF): A chemically resistant plastic with excellent durability, often chosen for aggressive chemicals like acids and solvents.
• Cast Iron: Highly durable but susceptible to corrosion with certain chemicals. They are commonly used for demanding applications in construction and mining. 

The check valve balls are in direct contact with the fluid and must be resistant to the medium you are pumping. Common materials include:

• Santoprene: A thermoplastic elastomer with good chemical resistance, typically used for water-based fluids and certain chemicals.
• PTFE (Teflon): Highly resistant to chemicals, suitable for aggressive solvents, acids, and high-temperature applications.
• Nitrile (Buna-N): Good for petroleum and certain chemicals but less resistant to extreme temperatures.
• Viton: Excellent for high-temperature and a variety of chemical applications.

Seats create the sealing surface for the balls, and their material affects the pump’s fluid compatibility. Common seat materials:

• Polypropylene
• Stainless Steel
• Santoprene and Buna-N

Diaphragms are crucial in AODD pumps, as they directly handle fluid and pressure. The choice of diaphragm material influences chemical resistance, flexibility, and temperature tolerance.

• Santoprene: A flexible, durable option for a range of chemicals, commonly used in general applications.
• PTFE (Teflon): Excellent chemical resistance, suitable for aggressive fluids, and has a longer lifespan in abrasive applications. 
• Buna-N (Nitrile): Good for petroleum-based fluids and general applications but limited by lower chemical and temperature resistance.
• Hytrel: A thermoplastic polyester with good chemical resistance, flexibility, and durability for various industrial fluids.

AODD Pump Limitations

The AODD family is very versatile and offers unique benefits but there are some limitations:

Requires Continuous Air Supply

AODD pumps need a reliable, continuous supply of compressed air to function. In remote locations or applications where compressed air is not readily available, additional equipment (like air compressors) may be needed, adding to setup costs.

Efficiency and Air Consumption

AODD pumps rely on compressed air to operate, which can lead to high air consumption, especially when running at high flow rates or under heavy loads. This can increase operating costs.

Compared to other types of pumps (like centrifugal pumps), AODD pumps typically have lower energy efficiency. This can be a drawback in applications where energy efficiency is a primary concern.

If energy efficiency is a priority, Graco offers electric motor-driven double diaphragm pumps. This provides you with the benefits of an AODD with significantly lower (up to 80%) operating costs. 

Pulsing

The “back and forth” nature of the pumping operation can result in a pulsating flow. This can be mitigated with pulsation dampeners, but it may still not be ideal for applications requiring a steady, continuous flow.

Pressure

An Air-Operated Double Diaphragm (AODD) pump typically operates at a maximum pressure of around 100 psi, although certain specialty models can handle higher pressures. These pumps are generally not suitable for high-pressure applications that exceed their design limits. Most AODD pumps have a 1:1 pressure ratio, meaning the liquid discharge pressure matches the air inlet pressure. For example, if the air supply is set to 50 psi, the pump will produce a liquid discharge pressure of approximately 50 psi.

Ready to Choose the Right AODD Pump?

Explore our selection of Air-Operated Double Diaphragm (AODD) Pumps, tailored for a wide range of applications. Our team is ready to assist you in finding the perfect pump for your industry’s needs.

Corn, or any crop for that matter, requires nutrients to grow. In the pursuit of better yields the need for precise and timely application of these nutrients is almost as crucial as the type of nutrient itself. Accomplishing this often means applying liquid fertilizer even at the planting stage. 

Accomplishing this requires a liquid delivery system on your planter. Today we are going to look at a variety of system options, explain their pros and cons, and determine what systems are best for a variety of scenarios.  

Article Table of Contents - Click to Jump to a Section:

• Fertilizer System Overview
• Fertilizer Tanks
• Rate Control
• Pumps
• Blockage Monitoring
• Distribution
• Fertilizer System Examples

Basic Planter Fertilizer System Overview

For the purposes of this article, when we refer to different types of fertilizer systems, we are talking about the complete collection of equipment and devices used to deliver the liquid fertilizer. Including the pump, controls, hoses, valves, flow meters, etc. These systems vary widely in their complexity from the simpler systems with 12-volt pumps, to the more elaborate automatic systems with electronic flow monitors for each row. 

Many Options to Choose From

There are numerous options for each component of a planter fertilizer system because every operation has unique needs based on factors like fertilizer type, equipment, and budget.

Putting a system together requires consideration of these factors and ultimately selecting the components that provide the features you want while remaining easy enough to install and operate. 

Fertilizer System Overview

We will get into more details about different types of systems in a moment, but first, let’s look at the basic layout of a fertilizer system. While different fertilizer methods (2X2, in-furrow, etc.) will require some slight variations, these basic components are going to be required in some form.

Fertilizer System Diagram

Fertilizer Tanks

Poly tanks are the go-to option for a wide range of fertilizers, agrochemicals, and soil biologics. Most tanks used in fertilizer delivery systems are either mounted on the planter or the tractor. No matter which setup you prefer, there are kits to accommodate several different planter makes/models as well as saddle tanks and helicopter tanks for tractors. 

You can browse the various tank options here:

These kits make it pretty easy to identify a tank or set of tanks that will fit your equipment, but there are dozens of other tank sizes and shapes available if you are looking for something to fit a unique scenario. 

Rate Control

When it comes to controlling the system, there are two primary categories: automatic and manual control. Rate control refers to the mechanism used to change the volume of liquid applied. Simply put, you can opt for a system that automatically adjusts the flow as you speed up or slow down or one that requires you to manually make the adjustment. 

Manual rate control systems are generally going to be simpler to use and less expensive. This also means, however, that they lack the convenience of automatic rate control systems. Typically, they do not accommodate prescription applications or data collection as an automatic system might. If you want more information, look at this comparison between auto and manual rate control. 

Pump Type

Pump type is another vital aspect to consider, and the main types used for fertilizer application are centrifugal, diaphragm, piston, and squeeze pumps. Here are the pros and cons of using each type:

For more details on each pump type, be sure to read our article about choosing the best fertilizer pump for your planter.

Blockage Monitoring 

Monitoring fertilizer applications is essential for efficient application. Accurate flow monitors help to prevent overuse that can harm plants and waste money. Monitoring systems detect clogs early, preventing missed application areas.  

Just like with pumps and controls, there are blockage monitoring systems ranging from simple to more complex electronic meters.

“Redball”/”VisaGage” Sight Gauges

The most basic monitoring option is the liquid flow sight gauges also known as “Redball” monitors or “VisaGage” monitors. Several different companies make a version of these tools, but they all function the same.

They consist of a series of clear vertical tubes, each corresponding to a specific row. As liquid flows through the system, colored indicator balls rise in the tubes, showing the flow rate for each row in real-time. If one ball is significantly lower or higher, it signals a potential issue that the operator can address.

Flow monitors like Redball and VisaGage use color-coded balls with specific weights to indicate flow rate ranges. Lighter balls, suitable for low flow rates, require less pressure to lift, while heavier balls are designed for higher flow rates and pressures. Intermediate-weight balls cover medium ranges. The color coding allows operators to quickly and visually confirm the flow rate, simplifying monitoring and eliminating the need for manual measurements.

Every brand offers their version of visual spray monitor variations to work with different pump types and system setups. There are manifold versions and squeeze pump versions, with threaded or push-to-connect ports. You can check out the various options available here:

• John Blue VisaGage II Monitors
• Wilger Spray Monitors
• Redball Spray Monitors

Electronic Flow Sensors

In some instances, it can be hard to see the balls in the visual monitors due to the dark color of fertilizer or biological product. Unlike traditional visual flow columns, electronic flow monitor systems provide an audible alarm when a row is potentially blocked, ensuring operators can address problems quickly. Several electronic flow monitor systems exist that allow you to monitor all the rows on a console in the cab of the tractor:

CDS-John Blue Liquid Blockage Monitors (LMBS)

John Blue offers blockage monitor sensors that can be added to their visual monitors. These sensors have magnets that sense the ball inside the flow monitor columns, and when a ball drops below the desired range the system gives you a visual and audible indication on a display in the cab. 

 John Blue offers both a wired version with a simple display panel and a wireless version that can be paired with an iPad. The wireless iPad version provides a visual indication of the ball levels in each monitor while the simpler wired version only provides an indication if there is a block.

Wilger Electronic Flowmeter (EFM)

The Wilger EFM is an electronic flowmeter which installs in the liquid line of each row. The EFM uses a paddle wheel to measure the flow rate and sends a wireless signal to a tablet in the cab. Both color-coded visual indicators and audible alarms can be set to user preference for near-instantaneous monitoring of each row. The Wilger EFM system can monitor up to 196 separate rows, up to 10 sections, and can be easily retrofitted to your existing visual spray monitors. 

Check out the Wilger EFM system here. 

Distribution

While major components like the tanks and pump may be the costliest items, your distribution system should not be overlooked. If you do not have the proper method to evenly divide the fertilizer over each row, your ROI will greatly decrease. 

Flow dividers, orifices discs, and microtubing are all viable options, but how do you decide which one to use?  Well, the type of pump you use will ultimately determine which route you take. Let’s look at the primary methods of flow distribution and when to use them.  

Orifices Discs

Orifices are small stainless discs that control the flow rate by restricting the flow of liquid. Orifice discs are a simple and cost-effective distribution method which are typically used in 12V or centrifugal pump systems. They can be used as the nozzle or outlet and “dribble” fertilizer on the ground or installed inline ahead of a fertilizer rebounder or stainless tube.

Orifices can also be installed on the top of the visual flow monitors (Redball). The benefit of this is less components down near the row unit that can get plugged up or potentially damaged. 

*Stainless orifice disc and 18999EPR gasket installed in check valve nozzle bodies and cap.

Microtubing

One drawback of using orifice discs is that they are prone to plugging, especially when using products that have suspended solids in them.  , on the other hand, provides the same metering ability as an orifice with a larger fluid path, and this larger fluid path reduces the risk of blockages happening.

Different size diameters of tubing correlate to different flow rates (GPM).  The tubing acts like an orifice, restricting the flow to deliver certain flow rates at various pressures. The difference is that the inside diameter of the tubing does not need to be as small as an orifice that provides the same relative flow rates because the friction loss of the fluid is extrapolated out over the entire length of tubing. In short, the fluid passes through a wider opening and has less risk of plugging while still delivering the same flow rates. 

Microtubing is a great option with soil biologicals and really viscous fertilizers. You can check out the different Identifying the proper size requires doing some math, you can reach out to us for help. 

Flow Dividers

A flow divider is a device that splits the liquid that enters it evenly across each outlet. It is not simply a manifold; it is specially designed for even distribution. There is no need for orifices or additional metering as there would be with a basic manifold.  

Flow dividers are used with ground-drive piston pumps. The total rate you want to apply per acre is set on the pump. Whatever the incoming flow rate from the pump, the divider splits it up accurately.

Explore John Blue Flow Dividers

Fertilizer Placement

Getting the fertilizer delivered to the desired target is vital. In many cases, the fertilizer is simply dribbled on the ground but there are specific tools for in-furrow/pop-up and 2x2 applications. Totally Tubular stainless steel placement tubes are precision-engineered for several planter models and will allow you to apply fertilizer efficiently.

Planter Fertilizer Setup Examples

12-Volt Pump Fertilizer Systems

Building your planter fertilizer system around a 12V pump is a low-cost, simple option. The basic setup would include the pump, pump speed controller, flow gauges, check valves, and orifice discs. In addition to these pieces, you will also need hose, fittings, zip ties, etc. 

Here is what this complete setup looks like: 

Dultmeier offers pre-boxed kits that contain components for 6-, 8-, 12-, and 16-row planters. These kits can also be customized for drills or planters with any number of rows or dual product placement needs. You can also easily upgrade from the basic sight gauge monitors to electronic flow monitors if desired.  You can see all the options

12-Volt Fertilizer Pump System Pros 

• Low cost
• Simple to setup
• Simple to troubleshoot

12-Volt Fertilizer Pump System Cons

• 12V pumps not a long-term option as the motors and internals tend to wear out sooner compared to other pump types.
• Rapid pump cycling can lead to overheating
• Limited to about 5 gallons per minute flow rates

A 12-volt pump system will typically be adequate for 5-10 gallons per acre on 12-row planters traveling up to about 5 mph. You can use this GPM calculator to help determine the flow rate you will need from your pump. If you need to apply a rate above 10 GPA or have a planter larger than 12 rows, a centrifugal pump may be the right choice for you. 

You can replace the 12-volt pump in the above kit with a hydraulic-driven centrifugal pump and use all the same components except the speed controller. Instead of the speed controller, you will need a rate control console and regulating valve or a rate control console and pump equipped with a PWM motor. 

Ground Drive Fertilizer Systems

Another simple planter fertilizer option is to utilize a ground drive pump. It offers automatic rate adjustment because the pump is driven by a planter shaft or ground drive assembly, the speed of the pump changes in direct relation to the speed of the planter. This is accomplished without the need for a rate controller or other electronics. 

In addition to the pump, the other key components are the flow divider and the spray monitor columns. As mentioned earlier in this article, a flow divider evenly splits the liquid among each row. Because the fluid is already divided, we don’t need the manifold-style flow monitors. Instead “squeeze pump” or independent columns with individual inlets and outlets are used to monitor the flow.

Dultmeier offers all of these components in our “ground drive” planter kits to go along with a John Blue piston pump. The diagram below shows the layout of a ground drive fertilizer setup. Note that with a flow divider, there is no need for orifices downstream.

Ground Drive Fertilizer Pump System Pros 

• Simple to setup and troubleshoot
• Higher flow rates than 12V systems
• Automatic rate adjustment without electronics

Ground Drive Fertilizer Pump System Cons

• More expensive pumps
• Gritty products or biologics with suspended solids may damage the pump

Conclusion

Choosing the right planter fertilizer system is crucial for maximizing crop yield and ensuring efficient nutrient application. By understanding the components—tanks, pumps, flow control systems, monitoring tools, and distribution methods—you can tailor a system to your operation’s specific needs, budget, and fertilizer type. The key is ensuring all components work harmoniously for precise and reliable application.

For assistance in selecting or upgrading your system, Dultmeier offers a variety of solutions and expert support to help you achieve your goals.

Maintaining your RO system properly not only ensures spot-free results in your car wash but also extends the lifespan of your equipment. One of the most important aspects is replacing the RO membrane. This guide will cover how often you should change your RO membranes, what signs indicate it’s time for a replacement, and the tools and equipment you’ll need to perform this task effectively. Let’s dive in.

Understanding RO Membranes and Their Importance

An RO membrane is a core component of your RO system, responsible for filtering out dissolved solids, contaminants, and other impurities from the water. Over time, the membrane's ability to filter water diminishes due to several factors, primarily scaling and general wear and tear, making regular replacement necessary to maintain optimal water quality.

Chlorine filters are essential to prevent chlorine from entering the membranes, as chlorine will cause rapid damage and failure. Additionally, a water softener is typically required to reduce water hardness to zero before it enters the membranes. When newly installed, the membranes take TDS down to zero.

How Often Should You Change Your RO Membranes?

Generally, RO membranes can last up to about 1 to 5 years, but the exact lifespan depends more on system usage and water quality than on time alone. Rather than focusing on a specific timeframe, it’s best to monitor the Total Dissolved Solids (TDS) level in the water your system produces. When TDS levels start to rise, it indicates that the membrane is less effective and may need replacing. This approach helps you avoid unnecessary changes while ensuring optimal water quality.

Here are some key considerations to help you determine the optimal time to replace your membranes:

Water Quality and Pre-Treatment

• The quality of your incoming water greatly affects the lifespan of the membrane. High levels of water hardness, iron, or chlorine will greatly affect membrane life. If your water supply has high levels of these contaminants, you will likely need to replace membranes more frequently.

• Pre-treatment options, such as sediment filters, carbon filters, and water softeners are very important for extending membrane life by reducing the burden on the RO membrane. 

You can contact our sales team for help selecting pre-treatment options.

System Usage

• The more frequently your RO system is used, the faster the membrane will become filled with contaminants, and performance will go down. For car wash operations with heavy daily usage, you may need to replace the membrane more frequently.
• In contrast, for systems used less frequently or with lower output, a membrane will last much longer.

Regular Monitoring and Maintenance

Performing weekly TDS checks is a key to monitoring the condition of your RO membrane. A handheld TDS meter can help you measure the TDS levels in the permeate (filtered water). If TDS readings exceed 40 ppm, it’s time to replace the membrane, as spotting generally occurs at this reading and above.

Regular maintenance and monitoring can help catch issues early, preventing costly replacements and downtime. Cleaning the inlet filter and solenoid can prevent strain on the membrane. Your water softener should also be backflushed periodically. Many systems have an automatic backflush feature that cleans the filter media by flushing out accumulated contaminants, dirt, and debris, helping maintain the filter’s efficiency and lifespan.

Testing the TDS with a Handheld Meter

Step-by-Step Instructions for Testing TDS with a Handheld Meter

1. Prepare a Clean Sample Container:
• Collect a cup or use the cap of the meter to hold your water sample.
• Rinse the container thoroughly to ensure it is free of any contaminants.
2. Collect the Water Sample:
• Use the container to collect a sample of the permeate (filtered water) from your RO (Reverse Osmosis) system.
3. Turn on the TDS Meter:
• Remove the cap from the TDS meter.
• Press the ON button to activate the meter.
4. Insert the Meter into the Sample:
• Place the TDS meter into the water sample up to the “ribbed” section on the meter for an accurate test (see image below).
5. Swirl the Meter:
• Gently swirl the TDS meter in the water for about 10 seconds to ensure the water flows consistently around the sensor.
6. Hold the Reading:
• Press the HOLD button on the meter to lock in the reading. This will allow you to remove the meter from the water without losing the result.
7. Read and Record the TDS Level:
• Check the TDS level displayed on the screen in parts per million (ppm).
• The meter will hold this reading for approximately 20 seconds, giving you time to record the result.

Dultmeier Item #HMTDS4

Signs It’s Time to Replace Your RO Membrane

Apart from monitoring TDS, there are additional signs that indicate it may be time for a new membrane:

• High TDS Levels: If TDS readings start to increase rapidly or are above 40 ppm despite cleaning or flushing the system, this is a clear indicator that the membrane is no longer effective.
• Decreased Water Production: A significant reduction in the system’s output or water flow could mean that the membrane is fouling or needing service.
• Visible Spotting on Vehicles: For car wash systems, if you notice water spots on vehicles after washing, this suggests that the membrane isn't producing spot-free water.
• Increased RO System Noise: An underperforming pump or noisy operation could indicate that the membrane is placing too much strain on the system.

RO systems are complex and you can find more details in our guide to RO system troubleshooting.

Recommended Tools and Equipment for RO System Maintenance

To keep your RO system running smoothly, equip yourself with the following tools and replacement parts:

Replacement RO Membranes

Choose the right membrane based on your system’s specifications. Dultmeier offers a selection of RO membranes from several different manufacturers and systems.   

• Browse RO Membranes

TDS Meters

Handheld TDS meters are essential for regular monitoring. You can use these to quickly check if your membrane is maintaining water at the appropriate quality standards.

Pre-Treatment Filters

• Sediment Filters: Protect the membrane from debris and particles.
• Carbon Filters: Remove chlorine and organic compounds that can damage the membrane.
• Water Softeners: Prevent hard water scaling, extending membrane life.

Best Practices for Extending RO Membrane Life

Perform Regular Maintenance

Schedule routine checks on the prefilter, membrane, pump, softener, and carbon bottle. Replacing prefilters regularly will reduce the load on the membrane, ensuring it lasts longer.

Flush the System Periodically

Run a flush cycle to remove accumulated debris and scale from the membrane. This should be done according to your system's maintenance schedule or as needed based on water quality.

Dultmeier offers RO systems with automatic flush mode, you can learn more about these systems here.  

Invest in High-Quality Pre-Treatment Solutions

Adding carbon filters, sediment filters, or water softeners will help protect your membrane from harmful contaminants and extend its service life.

Monitor Water Quality Weekly

Using TDS meters for regular monitoring helps you detect when the membrane begins to deteriorate. By staying ahead of TDS increases, you can replace the membrane before it causes major issues.

Conclusion

Changing your RO membrane every 1 to 5 years is a general guideline, but regular monitoring and maintenance play a critical role in determining the actual replacement schedule. By keeping a close eye on TDS levels, addressing any performance drops, and using quality replacement parts and pre-treatment equipment, you can maximize the efficiency and lifespan of your RO system.

When it comes to sprayers, planters, and other liquid application equipment, choosing between automatic and manual rate control is one major aspect that has a massive impact on the convenience and efficiency of your system. Each option offers advantages depending on your operation's needs, equipment, and budget. This blog will break down the key differences between these systems, how each one works, and the pros and cons of both to help you make an informed choice between the two.

What is Rate Control?

At its core, rate control refers to how the system manages the volume of liquid applied per acre. Precise control ensures that chemicals are applied at the correct rate, avoiding under-application that could harm yields or over-application that could waste inputs and increase costs.

All rate control systems fit into two primary categories: manual and automatic control. The fundamental difference lies in how the system adjusts flow rates as ground speed changes. While automatic systems adjust the flow in real-time as you change speed, manual systems require you to adjust flow settings yourself. Let's dive deeper into each approach.

Manual Rate Control: Simplicity at a Lower Cost

Manual systems rely on the operator to adjust the application rate manually, either by changing the pressure in the system with a regulating valve or by controlling the speed of the pump motor/drive. This setup is typically much simpler and budget-friendly but requires more hands-on monitoring and manual adjustment during operation.

How Manual Rate Control Works

Manual rate control systems achieve the desired output primarily through two methods: varying pressure with a regulating valve or adjusting the speed of a pump motor/drive. Both approaches require hands-on operation and frequent adjustments to maintain accurate application rates.

The first method involves varying pressure using a manual regulating or bypass valve. In this setup, the operator sets the system’s pressure to match the desired application rate. For example, you might calculate that at 5 mph, 28 PSI is needed to deliver 10 gallons per acre (GPA). However, if your speed increases to 6 mph, you must manually increase the pressure to 33 PSI to maintain the same 10 GPA (these numbers are just examples). This method demands careful pre-calculation of operating pressures for different speeds, along with frequent adjustments throughout the application process.

The second approach involves using a mechanism to adjust the speed of the pump. Two common methods are using a rheostatic control to adjust the RPM of a 12-volt electric pump or a PWM valve to vary the flow of a hydraulic pump. These systems allow the operator to increase or decrease the pump’s speed to control flow rates. 

While the flow can be adjusted in real-time, it still requires manual input based on changes in ground speed. If you speed up, you need to increase the pump RPM to keep the application rate consistent, and if you slow down, you must decrease the RPM to avoid over-application.

For more details, you can examine the manual rate control plumbing diagrams here.

Pros and Cons of Manual Rate Control

Pros:

• Lower upfront cost: Fewer components mean a more affordable setup.
• Simplicity: Easier to install and maintain with fewer parts to troubleshoot.
• Flexible with smaller operations: Suitable for fields where speed changes are minimal or predictable. Best option for skid sprayers or turf sprayers that utilize a spray gun rather than a boom. 

Cons:

• Labor-intensive: Requires constant monitoring and adjustment, which can be challenging when the operator has multiple things to monitor in the sprayer/tractor cab.
• Inconsistent applications: Greater risk of  over- or under-application due to human error  
• Less efficient: Not ideal for operations where speed frequently changes, like irregular terrain or fields with obstacles. Not ideal for prescription applications. 

You can see more information about setting up simple and cost-effective manual rate control in this article about planter fertilizer systems.

Automatic Rate Control: Precision and Convenience

Unlike manual rate control systems where the operator constantly must monitor speed and adjust as best they can to changes in the field, automatic rate control systems take the guesswork out of fertilizer and chemical applications. These systems are designed to automatically adjust flow rates as ground speed changes. This type of control is especially necessary in larger operations requiring maximum efficiency.

How Automatic Rate Control Works

Automatic rate control systems rely on sensors, controllers, and flow meters to monitor both ground speed and flow rate in real-time. As the system detects changes in speed—whether from variations in terrain or adjustments made by the operator—it automatically adjusts an electronic regulating valve (or PWM valve/motor) to maintain a consistent application rate, typically measured in gallons per acre (GPA).

These systems remove the need for manual input during the application, which frees up the operator to check for plugged nozzles, monitor wind conditions, and obviously steer. Many automatic rate control systems are integrated with GPS or in-cab monitors to enhance precision further. 

If you want more information then check out our article on the components needed for automatic rate control on a sprayer. 

Pros and Cons of Automatic Rate Control

Pros:

• Highly accurate applications: Reduces waste and ensures nutrients or chemicals are applied at the correct rate across the entire field.
• Increased efficiency: Operators can focus on other aspects of operation instead of manually adjusting settings.
• Ideal for large-scale operations: Handles varying speeds and field conditions seamlessly.

Cons:

• Higher cost: Advanced components like sensors, monitors, and GPS integration increase the upfront investment.
• More complex setup: May require professional installation and calibration
• Potential for downtime: Malfunctioning sensors or controllers can be more difficult to troubleshoot and halt operations until repaired.

Conclusion: Which System is Right for You?

Choosing between manual and automatic rate control depends on the specific needs of your operation. Manual systems offer a cost-effective solution for small farms, acreages, pastures, sports fields, etc. Basically, anywhere you can maintain a fairly constant speed on level terrain. On the other hand, automatic systems are ideal for large-scale or precision farming operations where efficiency and accuracy are paramount, though these systems come with higher upfront costs and more complex maintenance.

No matter which route you choose, Dultmeier Sales can help you identify the system that will meet your needs. Give us a call today and we’ll happily help you determine the best option for your operation.

⇒ Browse the Different Rate Control Options Available At Dultmeier Sales

Operating a sprayer from the cab of a tractor or other vehicle sometimes requires more than two hands, between adjusting pressure, changing boom height, ensuring nozzles don’t plug, not to mention steering. This can make it difficult to monitor and maintain your desired application rate. That’s where automatic rate control comes into play.

With the proper components, you can set your desired application rate (gallons per acre/ gallons per lane mile, etc.) and let the sprayer maintain this rate as conditions or speed change. This is a pretty standard feature on large-row crop sprayers, but it is possible to incorporate auto rate control into just about any type of broadcast sprayer. 

Today, we will examine how these systems work, the various components required, and how they fit together to accurately maintain the output of your sprayer.

Defining Automatic Rate Control on Sprayers

Automatic rate control refers to the ability of a sprayer to change the volume of fluid dispersed in a given amount of time to maintain a preset application rate without manual adjustments by the operator. This is accomplished via a combination of specific components working together. The operator sets their parameters, and these sprayer controls are then able to accurately deliver the desired result. 

Automatic rate control offers several advantages over less sophisticated manual sprayer controls such as having significant improvement in your accuracy, efficiency, and cost-effectiveness of agricultural spraying operations. 

Advantages of Automatic Sprayer Rate Control

• Accuracy: Real-time adjustments for precise application, reducing human error and ensuring consistent coverage across varying speeds and terrain.
• Efficiency: Minimizes over-application and under-application, optimizing the use of chemicals, fertilizers, and water.
• Cost Savings: Reduces product wastage, lowering input costs by applying only the necessary amount of liquid over the target area.

Pressure Versus Flow Meter Based Rate Control

When discussing automated sprayer controls, it is important to note that the output or application rate of a sprayer can be managed in two distinct ways: pressure-based control and flowmeter-based control. In pressure-based systems, the sprayer’s application rate is controlled by monitoring and adjusting the system’s pressure with a regulating valve to increase or decrease the sprayer's output.

In flow meter-based systems, the application rate is controlled by using a flowmeter to precisely measure the amount of liquid flowing through the system and using a valve or pump speed control to adjust the volume of liquid.

Both methods can be used to automate a sprayer's output, but the necessary components and overall system are slightly different. At Dultmeier Sales, we tend to see flow meter-based control systems more often, and that is what we will focus on in this article. 

Key Components of an Automatic Rate Control System

There are many ways one can go about setting up a sprayer. Pressure sensors, agitation, tank monitors, air clean out, boom section valves, etc. These pieces add valuable features, but they are not all required for the sprayer to monitor and maintain a rate automatically. The base components that are needed for a flow meter-based automatic rate control system include a rate controller, flow meter, regulating valve, and speed/GPS sensor. 

There are several variations of each component in terms of size, design, and brand, but they all work together in the same basic way. As the sprayer moves through the field, the speed sensor continuously updates the rate controller on the ground speed. The flow meter measures the actual liquid flow, and the rate controller compares this with the desired rate. If adjustments are needed, the controller instructs the pump or regulating valve to modify flow.

Automatic Rate Control System Setup

Each piece needed to automatically adjust your sprayer’s rate is important, but it is also just as important to install them in the correct way. In the image below, you can see a basic sprayer plumbing layout for a flow meter-based automatic rate control: 

The control console will require a wiring harness that connects to the flow meter (or PWM valve/motor - more on this below), a regulating valve, and the boom section valves (if applicable). The GPS radar or speed sensor will also connect to the rate control console. 

In the diagram, the flow meter is installed after the pump and prior to the regulating valve. This flow meter must be on the pressure or discharge side and the plumbing after it must be solely supplying the boom. This way it can tell the control console the exact rate of fluid being applied. 

The regulating valve could be installed before the flow meter, but then the adjustments from the regulating valve would disturb the steady flow of liquid and potentially cause inaccurate readings from the meter. 

Another option is to install the regulating valve in a return line to the sprayer tank. Again, there are several different ways to accomplish this, but the basic setup would look like this: 

Although boom section valves are not necessary for auto rate control, rate control consoles often come with boom section switches to control multiple valves. If you have a GPS-guided/mapping system, the section valves can be opened/closed automatically by the console.  

As referenced earlier, there are several different types of each component, size, types, brands, etc. Different brands can typically communicate with one another, you just need to ensure you have the proper wire harness and adapters. 

If you are unsure about a valve, flow meter, or other parts working together, give us a call. We can help with Raven, Micro-Trak, and TeeJet systems for agriculture, de-ice, and several other types of sprayers. 

Now let’s look at each piece of the puzzle a little closer.

Rate Controller

The rate controller is the "brain" of the entire system. It contains the electrical programming to process the data it receives from the flow meter and speed sensor and uses this information to adjust the flow by controlling the regulating valve or PWM (Pulse Width Modulation) valve or motor depending on the setup.

To do this the rate controller needs to know certain information. The operator supplies it with the desired application rate and the spacing of the nozzle on the spray boom. To make the proper adjustments as the speed changes, the controller also must be able to know the travel speed of the sprayer and the flow rate of liquid through the system. This is where the speed sensor/GPS sensor and flow meter come into play.

Recommended Rate Controllers:

Teejet 845: The 845 sprayer control is an easy rate controller to program and features five boom section valve switches, PWM pump control, and options for variable rate control. 

Micro-Trak Spray Mate: The SprayMate II is a compact controller that offers lots of operator-minded/user-friendly features to control multiple rates on the go. Micro-Trak’s SprayMate Plus offers both flow- and pressure-based control as well as PWM compatibility.

Raven 450: SCS 450 rate controllers provide feedback on a variety of spraying information such as total volume applied, total area covered, distance traveled, area covered per hour, and more. Works with regulating valves and PWM systems. Integrates seamlessly with other Raven products.

Flow Meter

Flow meters are a fundamental component in any automatic rate control system. A flow meter's function is to monitor the flow rate of the liquid being sprayed. It measures the gallons per minute (GPM) flowing through the system and sends this information to the rate controller.

There are different sizes of flow meters available, and the size corresponds to the flow range that the meter can accurately read. For example, a Raven RFM60P will register flows of 1-55 gallons per minute. This model is a fairly common flow meter for agricultural sprayers. 

View Flow Meter Options Here

Pressure Sensors

In a pressure-based control system, a pressure transducer or sensor would be used to monitor the PSI within the sprayer. The rate controller would make any appropriate adjustments based on this reading rather than a flow meter. Pressure sensors can still be used with a flow meter-based system to monitor the pressure in the system, while the flow meter is used to monitor the rate.

Speed Sensor / GPS

Tracking the sprayer's ground speed is another necessary factor in auto rate control. GPS radar receivers register and deliver this data to the rate controller. This input is necessary because the flow rate alone is insufficient for precise control; you also need to know how fast the sprayer travels. Faster travel speeds require a higher volume of liquid output to maintain the same rate. Likewise, a lower volume is needed at slower speeds.  

Most speed sensors use GPS to measure the speed; however, some options do not require a GPS signal and instead measure the rotation of a shaft/wheel. These can work great if you want to avoid investing in a GPS antenna/receiver or are concerned about getting a reliable GPS signal in your area.  

Speed Sensors Options:

• GPS Receivers
• Shaft Sensors

Regulating Valves

The regulating valve is the last piece of the puzzle. The rate controller uses the inputs from the flow meter and speed sensor to adjust the regulating valve according to the parameters you set in the controller.

In most scenarios, the regulating valve is an electric ball or butterfly valve. The electric motor rotates the ball or disc inside to increase or decrease the flow rate as needed. 

View Regulating Valve Options Here

PWM Valves/Motors

Some automatic rate control systems don’t use a regulating valve, and the flow is instead controlled with PWM (Pulse Width Modulation). In these PWM systems, the rate controller adjusts the speed of a pump motor to increase or decrease the flow rate. 

There are centrifugal, piston, and diaphragm pumps that come equipped with PWM-controlled hydraulic motors. With these types of pumps, the rate controller cable that would normally attach to your regulating valve instead connects to the PWM hydraulic motor: 

• ACE Centrifugal Sprayer Pumps w/PWM Motor
• Dultmeier Diaphragm Pump w/PWM Hyd Motors
• John Blue Piston Pumps w/PWM Hyd Motor

You can also buy a PWM hydraulic valve or PWM valve/motor combo to add to an existing pump:

• PWM Hydraulic Valves
• PWM Hydraulic Valve/Motor
• PWM Kits for Piston Pump

Key Takeaways

Although there are several ways to build your system, adding automatic rate control to your sprayer doesn’t have to be complicated. There are simple and affordable options that will give you the efficient and effective control that you desire, and which best suit your unique application needs. This article will help ensure that you have the right set of components and understand the basics of how those individual components work within the larger system. If you need any assistance, we here at Dultmeier Sales are happy to help you get your automatic rate control system up and running. 

If you need assistance setting up your sprayer, don’t hesitate to give us a call.

As a car wash owner, you know how frustrating those pesky water spots can be-they're the bane of a perfect wash and can leave customers dissatisfied. Ensuring your RO (Reverse Osmosis) system is functioning properly is crucial to delivering that spot-free shine every time.

In this guide, we'll dive into the reasons behind Spot Free RO system failures and how to fix the issue, helping you maintain that flawless finish and keep your customers happy. Let's get started on troubleshooting!

Common RO System Symptoms and What to Do About It

When your RO system is not performing up to par, there could be several possible culprits. Let's look at some of the most common symptoms you might face, the possible root causes, and how to fix them.

Symptom: Low Flow or No Water Production

Possible Cause: Clogged Pre-Filter

Pre-filters in an RO system are designed to capture large particles, debris, and other contaminants before water reaches the RO membrane. Over time, these pre-filters can become clogged, reducing the system's flow rate and potentially causing a disruption in water production.

Solution: Inspect and replace pre-filters if necessary.  Check the TDS with a meter to see if the membrane is making acceptable water (learn more about using TDS meter here). Sometimes you can see debris on the incoming side of the membrane when it is removed. If there is no noticeable debris it can be restricted throughout the field of the wrap of the membrane resulting in little to no flow.

Higher flow and higher TDS on the permeate side usually indicated a fouled or bursting membrane. Before replacing a membrane be sure the water softener is working properly, producing zero grain soft water. The softener brine tank should be cleaned periodically.

Possible Cause: Low inlet water pressure

For an RO system to function properly, it requires adequate inlet water pressure. If the water pressure is too low, the membrane will not be able to filter water effectively, leading to reduced flow or complete system shutdown.

Solution: Make sure the water softener is flowing correctly and that the bypass valve is fully closed. Check all valves ahead of the unit to make sure no shut-off valves are closed or not fully opened.

Possible Cause: Pump Failure

The booster pump plays a crucial role in increasing water pressure to the RO membrane. If the pump fails, the system will not have sufficient pressure to produce water, leading to reduced flow or no production.

Solution: Consult the MFG for troubleshooting help or Dultmeier sales.

Possible Cause: RO System in Flush Mode

Many Spot Free RO systems (like the Dultmeier DUSFR) are equipped with a flush mode, where water is run through the system to clean the membrane. During this cycle, water production will be reduced, and the system will appear to have low flow.

Solution: Consult your manual to determine how to shut off the flush mode. If you have a Dultmeier RO system, it is equipped with an automatic flush mode. After 3 minutes the system should return to normal operation. If the system does not return to normal operation after this type, examine the flush valve for debris. You can consult the manual for more details on the flush valve location.

Possible Cause: Incorrect Setting on the Pump Relief Valve.

The pump relief valve controls the pressure within the system. If it is incorrectly set, it can cause either low or excessively high water pressure, both of which can impact water production.

Solution: Consult the system manual to identify the proper relief valve setting and make any needed adjustments.

Symptom: Clogged Membrane 

Possible Cause: Carbon Not Flushed Properly

The carbon filter in an RO system is designed to remove chlorine, sediments, and organic compounds before the water reaches the RO membrane. If the carbon filter is not flushed properly upon installation or after routine maintenance, carbon particles can pass through to the membrane, leading to clogging.

Solution: Flush the carbon filter through a full cycle. Check the carbon filter for proper plumbing.

Possible Cause: Organic or Inorganic Matter in Water Supply

The incoming water supply can contain organic contaminants (such as bacteria, algae, or plant material) or inorganic materials (such as sand, rust, or other mineral particles) that are too large or difficult for the RO membrane to filter. Over time, these contaminants can accumulate on the membrane surface, clogging it and reducing its ability to filter water effectively.

Solution: Have water tested before replacing the membrane.

Managing your RO membranes is vital, for more information, you should read our guide on changing RO membranes. 

Symptom: Increased RO Production, High TDS, or Decrease in PSI

Possible Cause: Membrane installed upside down. 

The RO membrane must be installed in the correct orientation for water to pass through and filter properly. If the membrane is installed upside down, the flow of water is reversed, preventing the membrane from performing its intended function. This can result in poor water filtration, leading to high TDS levels and increased water production because the system isn't removing contaminants properly.

Solution: Turn the Membrane in the opposite direction.

Possible Cause: Chlorine in the RO system

Chlorine is harmful to RO membranes. If chlorine is not filtered out properly by the carbon pre-filter, it can damage or degrade the RO membrane. This leads to poor water quality (high TDS) and often increased water production since the membrane is less effective at filtering contaminants.

Solution: Inspect, and/or repair the carbon filter.

Possible Cause: Ruptured Membrane

A ruptured membrane can occur due to wear and tear, excessive pressure, or chemical damage (e.g., from chlorine). A ruptured membrane cannot properly filter out contaminants, leading to higher TDS levels and increased water production as the system allows more water to pass through without effective filtration.

Solution: Shut off the system and remove the membrane from its housing. Inspect the membrane for visible damage, such as tears, holes, or a complete rupture. If the membrane is damaged, it must be replaced immediately. Install the new membrane, making sure it is properly seated in the housing and oriented correctly.

Did you know Dultmeier Sales keeps a variety of RO membranes and Housings In stock? Be sure to check out the available options for pre-filters, chlorine carbon filters, RO filters, RO membranes, and sediment cartridge filters:

Reverse Osmosis Systems and Filters

Symptom: Water Flowing to RO Storage Tank When Unit is Not in Production

Possible Cause: Debris in inlet solenoid or defective inlet solenoid

The inlet solenoid valve controls the flow of water into the RO system. If debris clogs the solenoid or if the solenoid is defective, it may not close properly, allowing water to flow into the system even when it should not be producing. This could result in a constant flow of water to the tank, even when the system is not actively producing permeate (filtered water).

Solution: Remove the inlet solenoid valve according to your system's manual. Carefully inspect it for any signs of debris, dirt, or mineral buildup that may prevent it from closing properly. Use a soft brush or cloth to clean any debris or buildup around the valve. Ensure that the valve can open and close smoothly after cleaning.

After cleaning, reconnect the solenoid and turn the system back on. Listen for any clicking noises when the system is supposed to open or close the valve. If the valve is not working as expected, it may be defective. If cleaning does not resolve the issue or if the solenoid shows signs of wear, malfunction, or failure, replace the inlet solenoid with a compatible part for your RO system.

Symptom: Noisy Pump/ Underperforming Pump

Possible Cause: Inlet is obstructed, or restricted.

The pump relies on a consistent and unobstructed flow of water to function efficiently. If the inlet is blocked or restricted by debris, sediment buildup, or a clogged pre-filter, the pump has to work harder to move water through the system. This can result in unusual noises and reduced water flow, leading to underperformance.

Solution: Remove the prefilter and inspect it for signs of blockage or clogging. Replace the prefilter if it is dirty or past its recommended service life. Inspect the inlet lines for blockages or restrictions. These lines can accumulate sediment or scale, which may impede water flow. Clean the inlet lines by flushing them with clean water. If the lines are severely clogged, they may need to be replaced.

Possible Cause: Coupling, mounting bolts are loose. 

A pump with loose coupling or mounting bolts can cause excessive vibration and noise. Loose bolts can lead to pump wear and potential damage to the housing or connections.

Solution: Check Coupling Alignment: Inspect the coupling for any signs of wear or misalignment. If the coupling is visibly worn or damaged, replace it. Ensure all bolts securing the pump to the frame or motor are tightly fastened. Avoid over-tightening the bolts, as this could cause damage to the components. Ensure the pump remains securely mounted but allows for the necessary vibration isolation (if designed that way).

If the pump and motor are not properly aligned, this can cause additional strain on the components and lead to noise. Adjust the pump's position so that it is perfectly aligned with the motor.

You Can Find RO System Booster Pumps and Repair Parts Here

Possible Cause: The water source is off or not fully open

If the water source is not fully turned on or if the water valve is only partially open, the pump may be starved of water. This can cause cavitation inside the pump, which can lead to inefficiency and damage to the pump over time.

Solution: Ensure that the water source is fully turned on. Sometimes, water valves may appear open but are only partially allowing water through. Double-check to make sure the valve is fully open. Trace the water supply lines leading to the pump and ensure there are no blockages or kinks that might be restricting water flow. This includes valves, hoses, and any filtration units before the pump.

RO System Maintenance & Troubleshooting Tips

• Always disconnect the power before attempting any troubleshooting to avoid electric shock.
• Regularly flush the system to maintain optimal membrane performance and avoid clogs.
• Replace parts proactively based on the wear or inefficiency noted during daily inspections.
• Check the prefilter monthly: Replace after approximately 200 gallons or more frequently if needed.
• Inspect daily for leaks, ensure drain hoses are secure, and check pressure and flow gauges for abnormalities.
• Test for chlorine using the service valve and a test strip to avoid chlorine damage to the membrane.
• Monitor TDS levels: The permeate water should have a TDS reading between 0 and 40 ppm. If TDS is above 40 ppm, then the membrane should be replaced. Learn more in our guide on how to test and how often to change RO membranes
• Inspect the float switch regularly to ensure proper operation.

Keys to Remember

Maintaining a spot-free RO system requires regular inspection and cleaning of filters, membranes, and solenoids, ensuring proper water pressure and flow, and securing pump components. Addressing issues like clogged filters, misaligned parts, and proper valve settings prevents noise, low production, and high TDS. Routine maintenance ensures optimal system performance and extends the lifespan of your equipment.

Dultmeier sales car wash tech team has experience with Spot Free RO systems. Be sure to contact us for more help!

Whether you plan to use a starter fertilizer or soil biologicals, applying these liquids requires a proper pump. There are many different options available which makes selecting the best option important. Fortunately, most pumps can work in several different applications, the key is identifying a pump that will best handle your liquid, deliver your desired application rate and pressure to fit your system, and provide long-term value.

The sales crew at Dultmeier has been helping to set up planter fertilizer systems for decades. In this guide, we'll explore the various pump options for planters, delving into the strengths and weaknesses of each. From the high-volume capabilities of centrifugal pumps to the precise metering of piston pumps, and everything in between, we'll cover all you need to know to find options that will best meet your needs.

How to Choose a Fertilizer Pump for a Planter

When using a pump on a planter to apply fertilizer your focus should be on accuracy and reliability. A variety of different pumps can accomplish this, but they achieve this through various means, so that means there are pros and cons to each different type.

What to consider when comparing different types of fertilizer pumps:

• Durability: Pumps are made from different materials with varying degrees of resistance or durability when used in rugged conditions with corrosive & abrasive fertilizers.
• Serviceability: Some pump types are easier to rebuild than others.
• Flow Rate: There are pumps available to produce varying flow rates, so first determine your required flow rate per minute and identify a pump that will deliver this rate plus some cushion for agitation and increases in speed or application rate.
• Priming/Suction: Consider the pump's priming capabilities, especially in situations where it needs to draw fertilizer from a tank set below the pump level.
• Precision: Assess how accurately the pump can deliver the specified amount of fertilizer. Precision is crucial for consistent application and to avoid wastage or crop damage.
• Compatibility: Ensure the pump is compatible with the type of fertilizer being used. This includes checking for chemical compatibility with the fertilizer to prevent corrosion.
• Drive Type: Pumps can be driven by different means, such as PTO, hydraulic, or electric motors. Consider the available power sources on your equipment and how the drive type fits into your existing setup.
• Complexity: Some pumps are more complex in design, requiring more expertise to install and maintain. Simpler designs may be more user-friendly but could lack advanced features.
• Cost: Balance the upfront cost of the pump with long-term operational costs, including maintenance, repairs, etc. A more expensive pump may offer better durability and efficiency, reducing overall costs in the long run.
• Fit: Ensure the pump fits physically and functionally with your current equipment. This includes mounting options, connections, and space availability on your planter or tractor.

Consider the Overall Fertilizer System

Pumps are just one part of the entire fertilizer application system. The plumbing, control valves, nozzles, etc. work together with the pump to meter and distribute the liquid. The type of pump you use will affect how the rest of the system needs to be put together. The best pump for you will depend on the specific things you need your system to do.

Choosing the right pump requires that you know what type of system you desire. You might desire simplicity and ease of operation, or you might need more precision and the ability to vary your rate automatically. These pump features along with the available drive type and your budget will ultimately determine the pump that will work best.

We go into greater detail on the overall fertilizer system in our guide to planter fertilizer setups, but here are some of the main types of systems and how they differ:

• 12-volt Pressure Based: a 12-volt pump controlled via a rheostat
• Ground Drive: pumps driven by planter wheel or ground drive assembly, application rate is maintained automatically as planter speeds up or slows down
• Automatic Rate Control: The flow rate is automatically controlled with a rate controller, regulating valve, GPS/speed sensor, and flowmeter. Also allows for rate changes from the cab.
• PWM: automatic rate control with rate controller; pump motor speed is adjusted with a PWM valve or motor instead of using a conventional regulating valve.

Different Fertilizer Pump Types Used on Planters

Many of the types of pumps used on planters are similar to those used on a sprayer. There are also pumps designed specifically for planters/toolbars such as squeeze pumps and ground-driven piston pumps. You can see more specific details in our guide to sprayer pumps, but the basic types are:

• Centrifugal Pumps
• Diaphragm Pumps
• Piston Pumps
• Squeeze Pumps

Let's examine each type of pump used and identify the scenarios they work for applying fertilizer on a planter.

Centrifugal Pumps

The same type of hydraulic-driven centrifugal pumps used on sprayers can be used as a fertilizer pump on a planter. Centrifugal pumps are available that can provide flow rates well over 200 gallons per minute. If you have hydraulic outlets available, then they are a great option, especially for higher volume rates and larger planters.

For example, if you have a 24-row planter and want to apply a rate of 50 gallons per acre at 5 mph, you need more than 20 gallons per minute from your pump. So, at a minimum, you want a pump that can deliver this flow rate. To be safe you would want a pump that can deliver more than this to account for increases in speed, rate, and agitation.

Now, when these pumps are used on a sprayer, they are generally handling a liquid that is mostly water. On a planter, you are likely dealing with 100% fertilizer or a diluted solution of fertilizer, water, etc.

To handle the abrasive and corrosive nature of fertilizers, stainless steel pumps are recommended. Cast iron and poly will work, but they typically do not last as long. While stainless is usually the best option, it does depend upon the specific type of fertilizer or liquid being used. Many centrifugal pump manufacturers, like Ace and Hypro, offer a severe-duty mechanical shaft seal that is made to hold up better to abrasive material. Standard seals will work, but again, they may not last as long.

It is always vital with a standard centrifugal pump that you don't run it dry. This will knock out the seal quickly. However, there are "wet seal" centrifugal pumps that are protected from running dry. These pumps have a reservoir with a coolant/anti-freeze to lubricate the pump so if the pump is starved of fluid, the seal is still lubricated.

Pros of Using Centrifugal Pumps for Planter Fertilizer Application:

• High volume
• Easy to maintain and rebuild
• Good for 2x2
• Long service life, especially stainless steel

Cons of using a centrifugal pump on a planter:

• Hydraulic outlets needed
• Cannot run dry (unless wet seal pump)
• Straight centrifugal pumps are not self-priming and are limited in where they can be installed.

System Requirements When Using a Centrifugal Pump:

Centrifugal pumps need a mechanism to control the flow. Typically, this requires a flow meter, regulating valve or PWM hydraulic motor, along with GPS or speed sensor, and a rate controller. Centrifugal pump setups are relatively more expensive than some other setups.

For more information on the overall fertilizer setup including controls, monitoring, and metering, refer to our full guide to planter fertilizer systems.

Centrifugal Pumps Options for Planters:

• Standard Hydraulic Driven Pumps
• PWM Hyd Motor Pumps

12-Volt Diaphragm Pumps

One of the most cost-effective ways to get a starter fertilizer applied is with a 12-volt diaphragm pump. They are especially convenient for someone wanting to add a simple setup to a planter that can be installed easily. 12-volt diaphragm pumps do have some limits. They have a maximum effective flow of about 3-6 GPM. This means they are suited for application rates of up to about 10 GPA for smaller planters (6-12 rows) and about 5 GPA for larger planters (24 row+).

12-volt pumps are small and lower cost than other types of pumps. They can be easily installed about anywhere you can supply 12-volt power. It is also easy to adjust the pump output using a rheostat motor controller. This simple controller lets you increase or decrease the pump output from the cab as you speed up or slow down.

Advantages of 12-Volt Diaphragm Pumps:

• Low cost relative to other pump types
• Simple and easy to install

Disadvantages of Diaphragm Pumps for Fertilizer:

• Lower flow compared to other pump types
• Typically do not last as long as other pump types

System Requirements for 12-Volt Diaphragm Pumps:

A complete setup requires a pump speed controller, flow monitors, and orifice discs to regulate the output of the pump and apply the correct amount of liquid. This is one of the simplest and lowest-cost ways to apply a starter fertilizer in-furrow.

Dultmeier offers 12-volt pump kits that include the pump, monitors, speed controller, and plumbing components to install on your planter. Be sure to check this page for a complete list of the kit components. Don't worry we can make any changes to the kit if you need it!

Hydraulic Driven Diaphragm Pumps

12-volt electric is not the only type of diaphragm pump that can be used to apply fertilizer. A larger, high-pressure diaphragm pump is another option that delivers more flow and much higher pressures than the small 12-volt motor versions.

These pumps have excellent suction lift, meaning more flexibility where they are installed vs centrifugal pumps that need to be flooded. These pumps can handle thick and viscous fertilizers with high solid content. The gearbox is lubricated with oil. There is virtually no concern if you run the pump dry.

This type of diaphragm pump can be driven via a number of different means. Ground drive, engine, etc. The most common option on planters is a hydraulic motor. This may be a conventional hydraulic motor or PWM controlled motor.

Advantages of Diaphragm Pumps:

• High volume potential
• Higher pressure capability compared to other pump types
• Self-priming
• Can run dry
• Ability to handle viscous products

Disadvantages of Diaphragm Pumps for Fertilizer:

• Lower flow compared to centrifugal pumps
• Requires pressure relief valve
• Routine maintenance required

Diaphragm Pump System Requirements:

A diaphragm pump setup will require a rate controller with a flow meter and a regulating valve to control the amount of fertilizer you apply. Diaphragm pumps with PWM hydraulic motors are also available. With PWM you still need the controller and flow meter but instead of using a regulating valve to control flow, the PWM controls the speed of the pump.

Piston Pumps

Piston pumps are another type of positive displacement pump used in several different industries. As you might have guessed, a piston pump gets its name from the mechanical means used to move the fluid. In this case, a reciprocating piston forces draws liquid in and forces it out of the pump chamber.

There are specific piston pumps designed for the agriculture world. The NGP series piston pump from John Blue is an extremely effective tool for liquid fertilizer application on planters, side dress machines, and other toolbars. They offer a very accurate way to apply fertilizers at a constant rate. These pumps can be driven in several ways, but the most common drive types when used on planters are ground drive and hydraulic drive.

Advantages of Piston Pumps for Fertilizers:

• Priming Capability - these pumps can prime or pull liquid from longer distances when compared to other pump types.
• Extremely accurate despite varying temperatures
• Auto-adjusting for speed changes (maintains application rate)
• Constructed of durable cast iron and stainless components. Properly maintained pumps can last many years.
• Field Serviceable

John Blue Piston Pump Service & Repair Video:

Disadvantages:

• Gritty products can damage pistons
• Lower flow compared to centrifugal pumps

Piston Pump System Requirements

As mentioned earlier, there are two main ways to drive a piston pump: ground drive or hydraulic.

Ground drive either with a dedicated ground drive assembly or planter hex shaft. Ground drive pumps offer extremely accurate performance and do not require all the electronic components like flow meters, regulating valves, or rate controllers.

Ground-driven pumps do require that you calculate the proper pump setting and select sprockets to ensure the crankcase of the pump is rotating at the speed needed to deliver your desired rate. John Blue provides a tool that lets you quickly determine the correct settings with their NGP piston pump setting calculator.

From there you simply need to ensure that you evenly distribute the liquid among each row. This will require a flow divider manifold or orifice discs as well as a set of site gauges to monitor the flow going to each row.

John Blue Ground Drive Piston Pump options:

• NGP Series

Ground Drives:

• Universal ground drive assy
• Planter hex shaft drive assy

NGP Piston Pumps with Hydraulic Motor

If you prefer, you can drive an NGP piston pump with a hydraulic motor. The motors have a PWM valve that allows you to control your rate by varying the speed of the motor. While this method does not require a regulating valve, you will need a GPS/speed sensor and a flow meter in addition to a rate controller.

• John Blue NGP PWM Hyd Piston Pumps

Squeeze Pumps

A squeeze pump is unique in that it is designed specifically for planters. They are effective at accurately and evenly distributing fluid over each row. They do not require any additional components such as rate controllers, regulating valves, distributors, etc. Just typical plumbing and sight gauges if desired.

Advantages of Squeeze Pumps

• Simplicity
• Maintains rate when you speed up or slow down
• Pump stops when the planter stops

Disadvantages of Squeeze Pumps

• Not as versatile as other pump types
• Limited pump options available (6 row, 8 row, 12 row, 16 row)

System Requirements for Squeeze Pumps

A fertilizer setup using a squeeze pump is very simple. The pump is ground-driven, so the output is directly related to the speed of the planter. This means you dial in the output you need, and your desired application rate is maintained. There is no need for regulating valves or electronic flow meters.

The pump also serves as the manifold that evenly distributes the liquid over each row. The only additional components you need would be flow monitors so you can watch each row for plugs or low flow.

• Squeeze Pumps
• Squeeze Pump Flow Monitors

Conclusion

In conclusion, selecting the best fertilizer pump for your planter system requires careful consideration of several factors, including the type of fertilizer, flow rate needs, precision, and compatibility with your setup. Each pump type-from centrifugal and diaphragm to piston and squeeze pumps-offers unique strengths and trade-offs. Whether you prioritize high volume, precision desired, or simplicity, there's a pump to meet your specific requirements.

At Dultmeier, we understand that no two planter setups are exactly the same, and our team has decades of experience helping customers choose the right pumps for their systems. Whether you need a robust hydraulic-driven pump for high-volume applications or a simple 12-volt diaphragm pump for a smaller planter, we're here to guide you through the selection process. Don't hesitate to reach out for personalized recommendations or browse our selection of pumps and complete fertilizer systems to get started!

A sprayer's job is to distribute fluid over a designated area. No matter what type of sprayer at the center of the system is a pump. There are nearly endless different types of sprayers. They are built for several applications and require different types of pumps to deliver the flow characteristics necessary to complete those different spraying tasks.

At Dultmeier Sales, pumps are not just the center of a sprayer, they are at the center of our business. We sell, service, and support a wide variety of pumps for all types of sprayers. In addition, we prioritize understanding the different types, how they operate, and what pump works best on different sprayers.

In this guide, we will look at all the different types of pumps used on sprayers. We will examine how each pump operates and how they compare in terms of flow rate and pressure. In addition, we will offer real examples so you can see exactly how each pump is used. You'll be able to understand what type of sprayer pump will work for your application.

Different Types of Sprayer Pumps

While there are several variations of each type, the different pumps used on sprayers are centrifugal, roller, diaphragm, and piston pumps. Each pump is unique in its design and performance. Let's explore each type to understand how they operate and when to use them.

Centrifugal Pumps

• Pump Family: Centrifugal
• GPM Range: 0 to 500+
• PSI Range: 0 to 150

Centrifugal pumps use an impeller to move water or other fluids by using centrifugal force. They are known for their ability to move high volumes of liquid at relatively low pressure. The most common centrifugal pump type used on a sprayer is a straight centrifugal pump. Self-priming pumps can be used, but a straight centrifugal pump is typically more efficient and capable of developing higher operating pressure.

A self-priming pump is capped at about 40-60 PSI depending on the specific pump. The straight centrifugal pumps designed for use on sprayers can produce well over 100 PSI. They are intended to accommodate the high travel speeds of self-propelled sprayers combined with the expanded operating ranges of modern sprayer nozzles.

Common Centrifugal Sprayer Pump Applications

• Agricultural Spraying: Boom sprayers, fertilizer toolbars, boomless sprayers, fertilizer delivery on planters.
• Turf and Landscape: Golf course sprayers, sports field sprayers, large acreage sprayers.
• Industrial Uses: Salt brine trucks and trailers, water trucks for dust control.

Advantages of Centrifugal Sprayer Pumps

• High Volume Output: Centrifugal pumps can handle large volumes of liquid, making them suitable for applications requiring substantial flow rates.
• Durability: These pumps are robust and can handle abrasive and corrosive chemicals, making them versatile for various spraying tasks.
• Simplicity: The design is straightforward, which makes maintenance and troubleshooting easier compared to more complex pump types.
• Cost-Effective: Generally, centrifugal pumps are less expensive to manufacture and maintain, providing a cost-effective solution for many users.

Disadvantages of Centrifugal Sprayer Pumps

• Low pressure: Centrifugal sprayer pumps have lower pressure capabilities compared to some other types of pumps like piston or diaphragm pumps. While centrifugal pumps can move high volumes of liquid, they do so at relatively low pressures.
• Cannot Run Dry*: Running a centrifugal pump without fluid can cause significant damage to the pump. A centrifugal pump requires fluid in the pump case to lubricate the seal. *There are lubricated seals or "wet" seal centrifugal pumps that can run dry.

Centrifugal Pump Drive Types

• Hydraulic
• PTO
• Belt Driven
• Engine Driven

Parts of a Centrifugal Sprayer Pump

• Impeller: The heart of the pump, which is responsible for imparting kinetic energy to the liquid. The design and size of the impeller significantly affect the pump's performance.
• Casing: Encases the impeller and directs the flow of liquid. It also helps convert kinetic energy into pressure energy.
• Seal: Prevents leaks and maintains the pump's integrity by keeping the liquid within the system.
• Suction and Discharge Ports: Inlet and outlet points through which the liquid enters and exits the pump.

You can find a more detailed examination of centrifugal pump components and how they affect the performance of a pump in this guide to centrifugal pumps for fertilizer.

View All Centrifugal Pump Options

Roller Pumps

• Pump Family: Positive Displacement
• GPM Range: 2 to 60
• PSI Range: Up to 300
• Applications: Small and medium-sized boom sprayers, turf sprayers

Roller pumps use rollers inside a cylindrical housing to move liquid. As the rollers rotate, they create a vacuum that draws liquid in and then pushes it out. Roller pumps are very common on 3-point sprayers crop and turf boom sprayers, because they are self-priming, develop consistent pressure, and are less expensive compared to other types of sprayer pumps.

A roller pump is part of the positive displacement pump family. This means that a consistent volume of fluid is delivered with each cycle (in this case shaft revolution), regardless of the discharge head in the system. Simply put, you can spray at 60 psi if you want because the pump overcomes the restriction in the system. With a centrifugal pump, the system restriction will affect your operating pressure much more.

The larger roller pumps can produce about 50-60 GPM, limiting the size of the sprayer they can be used on. A roller pump can be repaired but the standard cast iron housings do have a limited life span. Friction eventually wears the pump housing to a point where the pump will no longer work efficiently.

To combat the wear and corrosion of agrochemicals and fertilizers, there are Ni-resist and Silvercast pump housings that last much longer than the standard cast iron roller pumps.

Advantages

• Pressure Output: Capable of producing consistent and generally higher pressure than a centrifugal pump.
• Self-Priming: Can draw liquid from a lower level, making them easy to start and use.
• Compact Design: Small and easy to integrate into different spraying systems.
• Can Be Reversed: Many roller pump models can be reversed so you can drive it either clockwise or counterclockwise. Consult the manual of your specific pump for details.
• Cost: Less expensive compared to other sprayer pump types. Especially when PTO driven since it does not require an engine or hydraulic motor.

Disadvantages

• Wear and Tear: Rollers wear out, especially when used with abrasive chemicals.
• Limited Flow Rate: Not suitable for applications requiring high flow rates.
• Maintenance: Regular maintenance is required to ensure optimal performance.
• Limited Lifespan: Wear and corrosion can increase the Internal clearance between the pump housing and rollers to the point that the pump no longer works effectively.

Drive Types

• PTO
• Belt Driven
• Electric Motor
• Gas-Engine

Parts of a Roller Pump

• Rollers: The moving parts inside the pump that create suction and discharge action.
• Rotor: Holds the rollers in place and drives their motion.
• Housing: Encases the rollers and rotor, providing a sealed environment for the liquid to move through.
• Shaft: Driven by PTO or motor and spins the rotor.
• Seals: Prevents leaks and maintains the integrity of the pump system.

Check out the Different Roller Pump Options

12-Volt Diaphragm Pumps

• Pump Type: Positive Displacement
• GPM Range: 1 to 5
• PSI Range: Up to 100+
• Applications: ATV/UTV sprayers, spot sprayers, small boom sprayers, low-volume chemical transfer

12-volt diaphragm pumps are very common and versatile. They are used on small sprayers because they are easy to power with a battery and relatively low in cost. These pumps work well with a wide variety of agrochemicals, cleaners, and other liquids, especially when diluted. They are self-priming, and they can run dry.

One standout benefit of the 12-volt sprayer pump is the demand switch. This feature shuts the motor off when you close a valve on the discharge side of the pump. When the valve is closed, the pressure increases, tripping the demand switch and shutting off the motor.

The most common application of this is when you are spot-spraying with a trigger wand or spray gun. When you pull the trigger, your pump turns on, when you release the trigger, the pump stops. This conserves your battery life and prolongs the life of the pump as it only runs when needed.

A 12-volt diaphragm pump can be used on smaller boom sprayers. However, they may only be able to work on booms with about 5-10 tips depending on the size of the nozzles that you use.

Advantages

• Portability: Lightweight and easy to transport, ideal for portable sprayer setups.
• Self-Priming: Can draw liquid from a lower level, making them easy to start and use.
• Low Power Consumption: Efficient operation with low electrical power requirements.
• Chemical Resistance: Can handle a variety of chemicals without damage.
• Demand Switch: The pump only runs "on demand", when you pull the trigger or open the valve to spray.
• Low-Cost: Very affordable compared to other pump types.

Disadvantages

• Limited Flow Rate: Maximum flow rates are about 5 GPM.
• Pressure Limitations: Maximum pressure is lower compared to other positive displacement pumps.
• Pump Life: The pump motor and other components do not have the same lifespan as other pump types. Parts can be replaced but the cost and time to repair may be nearly as much as a new pump.

Drive Types

• 12-volt Electric Motor
• This pump type is also available with 24-volt and 115-volt motors

Parts of a 12V Diaphragm Sprayer Pump

• Diaphragm/Wobble Plate: This assembly is driven by the motor; it has an eccentric bearing that causes it to "wobble" and this motion creates the suction to pull liquid into the pump and force it out.
• Check Valves: let fluid flow into the pump and stop it from going back out of the inlet port.
• Pump Housing: Contains the wobble plate and check valve assembly, and serves as the pump chamber where the liquid is pulled into the pump and forced out.
• Motor: Powers the movement of the wobble plate.

View 12-Volt Pump Options.

Large Diaphragm Pumps

• Pump Type: Positive Displacement
• GPM Range: 3-100+
• PSI Range: Up to 725
• Applications: Tree spraying, turf sprayers, fertilizer applicators

Large diaphragm pumps use multiple diaphragms and chambers to move large volumes of liquid at high pressures. These pumps are the preferred tool for long-range or vertical spraying such as tree spraying. The combination of high-flow rate and high pressures, when combined with the right sprayer gun and nozzle, results in a stream of liquid that can be propelled 50 feet or more in the air.

Video of Diaphragm Pump on Skid Sprayer:

Diaphragm pumps can also be used on boom sprayers or fertilizer boom sprayers. While they don't offer the same flow rates as a centrifugal pump of similar size, they can be a good option for sprayers or applicators when the fluid being sprayed is too thick or viscous for a centrifugal pump.

Advantages

• High-Pressure Output: Capable of producing very high pressures
• Durability: The flexibility of the diaphragm offers good resistance to a wide range of abrasive and viscous fluids.
• Chemical Resistance: Can handle a variety of chemicals without damage.

Disadvantages

• Cost: More expensive to purchase and maintain compared to smaller pumps.
• Complexity: More complex design requires more safeguards and proper installation. Troubleshooting can be more complicated than with other pump types.
• Maintenance: The diaphragms and pump oil must be changed periodically, typically every 500 hours or 3 months of use.

Drive Types

• Engine Driven
• Hydraulic Driven

Parts of a Diaphragm Sprayer Pump

• Diaphragms: Multiple flexible membranes that move to create suction and discharge action.
• Check Valves: Control the flow of liquid into and out of the pump chambers.
• Pistons: Push and pull the diaphragms to create the necessary suction and discharge, driven by the crankshaft.
• Crankshaft: Driven by the engine or motor, rotation of the crankshaft drives the pistons
• Gear Box: Allows diaphragm pumps to be directly driven by a gas engine at about 3600 rpm.
• Regulator/Control: Serves as the relief valve and provides pressure adjustment. Also directs flow from the pump outlet to different sprayer features such as spray gun, agitation, etc.

View All Diaphragm Pump Options

Piston Pumps

• Pump Type: Positive Displacement
• GPM Range: Approx 1 to 68
• PSI Range: Up to 120
• Applications: Fertilizer application on toolbars or planters.

A piston pump is more common for fertilizer application than it is for pesticide/herbicide application. They do not offer the flow rates needed for large boom sprayers, and they are not as forgiving to solids or abrasion as diaphragm pumps. However, they excel at delivering fluid accurately and consistently.

This pump works by using pistons to create a reciprocating motion that draws liquid into the pump chamber on the suction stroke and then pushes it out on the discharge stroke. This mechanism allows the pump to generate consistent flow.

There are piston pumps that are designed for high pressures (1000 psi +), but the piston pumps used for agricultural applications are geared to precision. They are often ground-driven, which makes them the simplest option for automatic rate control. A ground-driven piston pump does not require flow meters or regulating valves for automatic rate control. As you speed up or slow down the pump delivers the precise amount needed to maintain your application rate.

These pumps are also available with hydraulic motors and PWM valves. This allows you to control the speed of the pump with a rate controller and flow meter.

Advantages

• Accuracy: The pump pushes a consistent amount of fluid with each stroke, especially important when applying fertilizers.
• Durability: Robust construction for long-lasting performance in harsh environments.
• Priming: Excellent ability to prime offers flexibility when mounting the pump on a sprayer, toolbar, or planter.
• Easy to Service: The NGP piston pumps are designed to be field repaired. The check valves can be quickly removed and cleaned or replaced as needed.
• Self-Adjusting: A ground-driven piston pump automatically adjusts to your speed, delivering the precise amount needed without flow meters or regulating valves.

Disadvantages

• Cost: More expensive than other pump types that deliver similar flow rates
• Complexity: More complex pumps with many components.
• No solids: Requires filter prior to the inlet to protect check valves and pistons from damage.

Drive Types

• Ground Drive
• Hydraulic

Parts of a Piston Sprayer Pump

The piston pumps used for fertilizer application are more complex pumps than some of the other fertilizer pumps. They feature several components but these are the main ones:

• Plunger: Reciprocating action of piston rod and plunger draws in liquid and pushes it out.
• Check Valves: Control the flow of liquid into and out of the cylinders.
• Crankcase: Houses connecting rod and crankshaft

See all the Piston Pump Drive Options Here

Key Takeaways

The type of pump used on a sprayer can have a drastic effect on the performance. Understanding the different types of sprayer pumps and their attributes will ensure you have the best tool for your application. The Dultmeier Sales team has decades of experience and can provide you with insights and guidance in selecting and troubleshooting your sprayer pump.

Choosing the right pump can make all the difference in how smoothly your system runs, whether moving fertilizer, de-icing fluid, or pumping out a pit. One of the big questions people often ask is: which type of pump gives you the highest flow rate?

The type of pump designed to produce the highest flow rate is a centrifugal pump. These pumps are intended to handle large volumes of liquid at relatively low pressures. They work by converting rotational kinetic energy, often from a motor, into energy in a moving fluid, which creates a flow rate that can be very high.

If you're looking to move a lot of liquid quickly, the centrifugal pump is usually your best bet. Let's take a closer look at why these pumps are so good at handling large volumes with ease.

Why Centrifugal Pumps Excel in High-Flow Rate Applications

Centrifugal pumps are engineered to move as much liquid as possible in an efficient manner, making them the go-to choice when high flow rates are needed. Other pump types are designed to handle thicker liquids or to generate higher pressures, but a centrifugal pump's primary purpose is to transfer fluids that are relatively less viscous. Think water, fuels, fertilizers, and other flowable liquids.

How Centrifugal Pumps Work

Centrifugal pumps function by converting rotational energy into fluid flow, making them exceptionally efficient for high-volume transfer. You can read more on the specifics in our centrifugal pump guide. The short explanation is the heart of a centrifugal pump is the impeller. As the impeller spins, it imparts velocity to the fluid, pushing it outward from the center where the fluid enters, to the edges where it exits. This process creates a continuous, smooth flow of liquid.

High Speed Equals High Flow

The faster the impeller spins, the more kinetic energy is transferred to the fluid, resulting in a higher flow rate. This ability to maintain a steady, high-speed transfer of liquid makes centrifugal pumps ideal for applications that demand high flow rates.

Continuous Flow for High Efficiency

Unlike positive displacement pumps-such as gear pumps or piston pumps-that move liquid in cycles, centrifugal pumps deliver a continuous, non-pulsating flow. This is a significant advantage in applications where moving large volumes of liquid is essential, as it reduces turbulence and inefficiencies that can arise from intermittent flow. Because centrifugal pumps don't need to pause between cycles, they're more efficient for handling large volumes.

Scalability

One of the key benefits of centrifugal pumps is their scalability. These pumps can easily be adjusted to handle higher flow rates by increasing the impeller size or the speed at which the pump operates. This scalability is more straightforward compared to other types of pumps, where increasing the flow rate might involve more complex changes.

High Flow at Lower Pressure

Centrifugal pumps shine in applications where high flow rates are needed at relatively low pressures. While they might not be the best choice for high-pressure needs, their design is optimized to move large amounts of liquid with minimal energy input.

Flow Rate Capabilities of Centrifugal Pumps

The flow rate of a centrifugal pump can vary widely depending on the size of the pump, the speed of the impeller, and the specific design of the system. These pumps can achieve flow rates ranging from a few gallons per minute (GPM) to several thousand GPM. For instance, centrifugal pumps used in large-scale agriculture can easily move hundreds of gallons in a minute. 

Common High-Flow Centrifugal Pump Applications

Railcar Unloading

Centrifugal pumps are ideal for transferring liquid fertilizer from railcars to storage tanks. In many scenarios flow rates of over 1000 gallons per minute are possible.

• View more high-flow transfer pump options

Dewatering

Centrifugal and submersible (a type of centrifugal pump) are ideal for moving water from construction sites, drainage pits, or any location where excess water accumulation could interfere with operations.

• View high-volume submersible pump options here.

Industrial Cooling

In cooling towers, the volume of water that needs to be circulated is immense. Centrifugal pumps are ideal for this purpose due to their ability to handle high flow rates. These pumps ensure a continuous and reliable flow of water through the cooling tower.

Industrial and Manufacturing Processes

Centrifugal pumps are essential for the precise and reliable transfer of raw materials, intermediates, and finished products. Additionally, when precise flow control is needed, these pumps can be paired with variable frequency drives (VFDs) to adjust the flow rate accurately.

• View industrial pump solutions

You can read this beginner guide to sizing a centrifugal pump. Also, Dultmeier engineers have several combined years of experience sizing pumps according to the specific needs of several high-volume applications. Be sure to contact us if you have any questions.

Factors Affecting Flow Rate

Several factors affect the flow rate of a centrifugal pump, including:

1. Pump Size: Larger pumps with bigger impellers can move more liquid per rotation, increasing the overall flow rate.
2. Impeller Design: The shape and size of the impeller blades, along with the speed at which the impeller rotates, play a crucial role in determining the pump's efficiency and flow rate.
3. System Head: The height and resistance the liquid must overcome (referred to as 'head') can impact the pump's performance. Centrifugal pumps are more efficient at lower heads, making them ideal for applications requiring high flow but not high pressure.

If you would like a more detailed explanation of system head and flow rates, be sure to read our guide on centrifugal pumps written by in-house engineer Tom Hansen.

Selecting the Right High-Flow Pump for Specific Applications

Although a centrifugal pump is the best pump type for high-volume transfer of several fluids, in some scenarios a centrifugal pump may not be the best option. Thicker fluids may require a gear or diaphragm pump. Applications that require high-flow and higher pressures such as hydro excavating or sewer jetting, will need a different type of pump.

Here are some common applications where a centrifugal pump may not be the best option and which pump types can offer the highest flow rate in each scenario:

Tree Spraying: While a centrifugal pump offers enough volume, spraying tall trees requires more pressure than they can deliver. This is where high-flow diaphragm pumps come into play. They can deliver flow rates ranging from a few gallons per minute to over 100 while producing pressures from 250 psi and more.

Liquid Feed Transfer: The combined viscosities and occasional cold temperatures of many liquid applications require a gear pump for high-volume transfer. Centrifugal pumps work in some scenarios but are limited when handling thicker, more viscous liquids like molasses.

Learn more in our guide on how a gear pump works.

NH3: Vane pumps are used for high-volume transfer of anhydrous ammonia. Centrifugal pumps can struggle with the low viscosity and high vapor pressure of NH3, leading to issues like cavitation, reduced efficiency, and potential pump damage.

High-Pressure: Applications requiring higher pressures (think 1000 PSI+), and large volumes of fluid typically require plunger pumps or piston pumps. Pumps producing high-pressure and high flow rates do have significant horsepower requirements.

12-Volt Power: 12-volt motor pumps are available for applications where only 12-volt power is available. The flow rates that can be achieved by these pumps are limited to a maximum of about 20-25 gallons per minute. This is only achieved at very low pressures, about 5 PSI. There are 12-volt pumps that produce 1-5 GPM at much higher pressures, typically 40-60 PSI, making them much more versatile for low-volume applications.

Final Thought

Centrifugal pumps are the top choice for high-flow applications, efficiently moving large volumes of low-viscosity fluids at lower pressures. Their scalability and continuous, smooth flow make them ideal for industries requiring reliable, high-volume liquid transfer.

If you need help selecting and sizing a centrifugal pump you can reach out to our team. Our engineering department can provide flow analysis and expert guidance!