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Because the pump is literally the “heart of the liquid system” on a sprayer, ca

Because the pump is literally the “heart of the liquid system” on a sprayer, careful consideration must be made in selecting the right pump. Seldom is there only one pump that will do the job. To make a wise choice, you will need to know about pump types, how the pump is to be driven and the flow and pressure requirements for your specific spraying system and application. To ensure you can closely match the pump to your needs, Hypro manufactures five types of pumps: roller, centrifugal, diaphragm, turbine and piston pumps. “Positive displacement” vs. “Non-positive displacement” Hypro’s long line of pumps can be divided into two general categories: “positive displacement” and “non- positive displacement.” Roller, diaphragm and piston pumps are positive displacement. That is, the flow from the pump is directly proportional to the pump speed. This positive flow is why all positive displacement pump hook- ups must include a relief valve and bypass line between the pump outlet and the nozzle shut-off valve. Centrifugal and turbine pumps are non-positive displacement. In these pumps, a rotating impeller creates a centrifugal force that feeds the liquid through the system instead of capturing and discharging a fixed volume “per stroke” as rollers, pistons or diaphragms would do. Therefore, if the outlet is closed, the impeller simply continues to rotate harmlessly. That is why special relief valves are not required in centrifugal pump systems. Centrifugal Pumps (non-positive displacement) In centrifugal pumps, spray solution enters through the center of a rotating impeller that’s driven at speeds up to 6000 RPM. Spray solution is forced to the outer edge of the housing. This centrifugal force is what delivers the liquid to the nozzle. Traditionally thought of as low to medium pressure pumps, Hypro’s centrifugal pumps can deliver from 0-190 psi and flow rates up to 358 gpm. Because centrifugals have minimum surfaces to wear and no valves, they are very durable, easy to maintain and well suited for pumping abrasive and corrosive materials. Because centrifugal pumps operate at higher speeds, the PTO speed must be increased through a speedup gear drive, belt/pulley drive, gas engine drive, or a high-speed hydraulic motor. (Hypro has models specifically designed for each of these applications). The broad, versatile line includes models with rugged housings of cast iron, polypropylene and stainless steel that stand up to the wide variety of agricultural chemicals. Selecting the Right Pump 2 3 Roller Pumps (positive displacement) Hypro roller pumps are the number one all-around choice by farmers throughout the world. The rollers (from 4 to 8, depending on the model) revolve inside the pump housing to force the spray solution through the outlet to the nozzle. Roller pumps have a low initial cost and are extremely versatile. They operate efficiently at PTO speeds of 540 and 1000 rpm and have a wide pressure range of up to 300 psi and flow rates of 2 to 74 gpm. Roller pumps are self priming and easily adapt to PTO or gas engine drives. Specific seal, roller and casting materials can be selected for compatibility with certain herbicides, pesticides, fungicides and fertilizers. Diaphragm Pumps (positive displacement) Because of their design, diaphragm pumps provide excellent handling of abrasive and corrosive materials. The pumping cylinders (from 2 to 6) are separated from the piston chambers (Hypro’s are oil-filled) by a synthetic diaphragm. This keeps the spray solution from contacting and corroding the internal pump components. Diaphragm pumps are compact, self priming and produce medium-to-high pressures (275 to 725 psi) with flow rates of 3.5 to 66 gpm. Driven by 540 rpm PTO, gas engine or DC motor, diaphragm pumps are used for a variety of agricultural, horticultural and pest control spraying applications. Piston Pumps (positive displacement) Piston pumps are not unlike an engine. That is, they have a shaft, pistons and “intake” and “exhaust” valves. On the down-stroke, the inlet valve opens, filling the chamber with solution. On the up-stroke, the outlet valve opens, and the piston forces the solution to the nozzle. Piston pumps deliver relatively low flow rate (up to 10 gpm) at high pressure (up to 400 psi). The replaceable piston cups can be of leather, fabric or Buna-N rubber, depending on the type of solution to be sprayed. They can be driven by 540 rpm PTO, gas engine or electric motor. Their low volume/high pressure capability permits use in general spraying as well as task-oriented applications such as spraying fence rows and ditches, and hydrostatic testing. First line: Model Number Second line: Serial Number First & second digit: year (03=2003) Third through fifth digits: consecutive day of the year the pump was manufactured. Sixth digit: shift the pump was built on. Seventh through tenth digits: consecutive pump number built on the shift. Hypro Pumps Identification Coding Hypro uses serialized labeling to enable users to precisely identify the pump when ordering parts or requesting warranty service. Following is an example. Selecting the Right Pump 4 Pump Drives How a pump is to be driven is often a primary consideration in selecting the proper type of pump. If the power source has already been determined, the following chart may be of further help in selecting the type of Hypro pump that is best suited to your needs. Pump shaft rotation With many pumps, you need to specify which direction the shaft rotates… either clockwise (CW) or counter- clockwise (CCW). Hypro’s rules on shaft rotation are as follows: Rule #1 “Eyes on the end” Always view the rotation when you are facing the end of the drive shaft. If it turns clockwise, it is a clockwise shaft. Always use this rule for determining rotation of the pump shaft and for the power source shaft (PTO, for example). Once you have determined the rotation of the power source shaft, remember Hypro rule #2: Rule #2 “Opposites attract” A clockwise (CW) rotating PTO shaft will require a counterclockwise (CCW) rotating pump shaft, and vice versa. All shaft rotation references in this catalog are based on these two rules. You can use these pump types: If your power source is: Roller Centrifugal Turbine Diaphragm Piston direct coupled: 540 rpm PTO through gear drive: through belt/pulley: direct coupled: 1000 rpm PTO through gear drive: through belt/pulley: Hydraulic Motor 12 Volt DC Motor direct coupled: Gas Engine through gear reduction: through belt/pulley: Electric Motor direct coupled: through belt/pulley: PTO Shaft: clockwise (CW) rotation Electric Motor: counter clockwise (CCW) rotation Gas Engine: counter clockwise (CCW) rotation 5 Determining Pump Flow and Pressure Requirements Every pumping task has an optimum volume and pressure requirement. Determining that optimum (and selecting the pump that delivers it) is key to an efficient and economical spraying system operation. Pressure requirements for agricultural pumps are dependent on both the material to be applied and application targets. Soil-applied herbicides generally require a relatively low pressure pump rating of 30-60 psi with foliar-applied herbicides at the top end of that range and slightly higher. Insecticides and fungicides require higher pressure ratings of 100 to 500 psi. Pressure must be sufficient, in the case of heavy foliage field crops and orchard crops, to penetrate the leaf cover. In the case of orchard crops, pressure must also be sufficient to carry material up and over as well as into the canopy. A number of factors must be considered to properly determine the total flow you will need from your pump. They include: • Type of spray operation (broadcast, banding, low- level, etc.) • The chemical’s application rate, ground speed, boom width, hose length, tank agitation, etc. The spray task is the first consideration in determining flow rate and pressure needs. The following formulas and calculations may help. Calculating agitation requirements The pump must produce enough flow for both the application rate and tank agitation requirements. Too little agitation will not keep the solution in proper suspension and too much agitation may cause foaming. Here are rule of thumb formulas for calculating how much additional pump flow you will need for agitation. Liquids: Tank volume (gallons) x .05 = total agitation in gpm Wettable Powders and Flowables: Tank volume (gallons) x .125 = total agitation in gpm EXAMPLE: If you will be spraying a wettable powder from a 100-gallon tank, proper agitation will require 12.5 gpm additional flow from the pump. Factor in an “Excess Flow” Requirement It is wise to have some excess flow capacity so you will not end up with an undersized pump because actual operation conditions may cause changes in spray system performance (such as normal pump wear, operating at less than rated speeds, etc.). Hypro recommends you add an additional 20% to your calculated total pump flow requirement to compensate for these variables. Plumbing systems have a number of restrictions that will result in a pressure drop from the pump to the actual spray point. These must be taken into uploads/Litterature/ spraying-guide 1 .pdf