pressure compensated hydraulic pump quotation

These pumps are designed for applications where light weight design, lower displacements, and multiple configuration capabolities are design requirements.

This Pressure Compensated Piston Pump is one of many pumps that the Hydraulic Megastore has to offer and they are all available for next day delivery.

max flow: 21.5 GPMHyvair’s line of pressure compensated industrial piston pumps (PCP) are stocked with displacements from 0.49 cu.in/r. (8.0cc) to 4.27 cu.in/r. (70.0cc) and continuous pressure up to 3,000 PSI. All sizes in our industrial line are available with multiple control options from load sensing to dual pressure solenoid. Through drives are available on all pump sizes except the PCP33. The semi-cylindrical swash plate design allows for smooth, stable operation, increases efficiency and reduced noise by sealing pressure on its face. catalog pdf Cad File

422 hydraulic pump compensator products are offered for sale by suppliers on Alibaba.comAbout 48% % of these are hydraulic pumps, 6%% are pumps, and 3%% are construction machinery parts.

A wide variety of hydraulic pump compensator options are available to you, You can also choose from piston pump, gear pump and vane pump hydraulic pump compensator,as well as from 1 year, 6 months, and 3 months hydraulic pump compensator,and whether hydraulic pump compensator is hydraulic power units, or valves.

VARIABLE DISPLACEMENT, PRESSURE COMPENSATED AXIAL PISTON PUMP Rated Continuous Pressure: 3000 to 3500 PSI (207 to 241 bar) Rated Flow: 6.7 to 28.6 gpm (25.2 to 108.3 l/min) Max Displacement:...

A pressure compensator is a device built into some pumps for the purpose of automatically reducing (or stopping) pump flow if system pressure sensed on the pump outlet port, should rise above a pre-set desired maximum pressure (sometimes called the "firing" pressure). The compensator prevents the pump from being overloaded if an overload is placed on the hydraulic system.

A compensator is built into the pump at the factory and usually cannot be added in the field. Any pump built with variable displacement can be controlled with a compensator. These include several types of axial piston pumps and unbalanced (single lobe) vane pumps. Radial piston pumps can sometimes be built with variable displacement but do not lend themselves readily to this action. Most other positive displacement pumps including internal and external gear, balanced (double lobe) vane, gerotor, and screw types cannot be built with variable displacement.

Figure 1 is a schematic of a check valve axial piston pump, variable displacement, controlled with a pressure compensator. The pistons, usually 5, 7, or 9 in number, are stroking inside a piston block which is keyed to and is rotating with the shaft. The left ends of the pistons are attached through swivel joints, to piston shoes which bear against and slide around on the swash plate as the piston block rotates. The swash plate itself does not rotate; it is mounted on a pair of trunnions so it can swivel from neutral (vertical) position to a maximum tilt angle. The angle which the swash plate makes to the vertical causes the pistons to stroke, the length of stroke being proportional to the angle. Normally, at low system pressures, the swash plate remains at its maximum angle, held there by spring force, hydraulic pressure, or by the dynamics of pump construction, and pump flow remains at maximum. The compensator acts by hydraulic pressure obtained internally from the pump outlet port. When pump pressure rises high enough to over-come the adjustable spring behind the compensator piston, the "firing" pressure has been reached, and the compensator piston starts to pull the swash plate back toward neutral, reducing pump displacement and output flow. The spring in the compensator can be adjusted for the desired maximum or "firing" pressure.

Under working conditions, on a moderate system overload, the compensator piston reduces the swash plate angle just enough to prevent the system pressure from exceeding the "firing" pressure adjusted on the compensator. On severe overloads the compensator may swing the swash plate back to neutral (vertical) to reduce pump flow to zero.

Maximum Displacement Stops. Some pumps are available with internal stops to limit the tilt angle of the swash plate. These stops limit the maximum flow and limit the HP consumption of the pump. They may be fixed stops, factory installed and inaccessible from the outside, or they may be externally adjustable with a wrench.

Manual Control Lever. Some pressure compensated pumps, especially hydrostatic transmission pumps, are provided with an external control lever to enable the operator to vary the swash plate angle (and flow) from zero to maximum. On these pumps the pressure compensator is arranged to override the manual lever and to automatically reduce the swash plate angle if a system overload should occur even though the operator control lever is still shifted to maximum displacement position.

Basically the pressure compensator is designed to unload the pump when system pressure reaches the maximum design pressure. When the pump is unloaded in this way, there is little HP consumed and little heat generated even though pressure remains at the maximum level, because there is no flow from the pump.

Variable displacement pumps are usually more expensive than fixed displacement types, but are especially useful in systems where several branch circuits are to be supplied from one pump, and where full pressure may be required simultaneously in more than one branch, and where the pump must be unloaded when none of the branches is ill operation. If individual 4-way valves are used in each branch, each valve must have a closed center spool. The inlet ports on all 4-way valves must be connected in parallel across the pump line. However, if all branch circuits are operated from a bank valve of the parallel type, a pressure compensated variable displacement pump may not be necessary; a fixed displacement pump, gear, vane, or piston, may serve equally well because the bank valve will unload the pump when all valve handles are placed in neutral, but when two or more handles are simultaneously shifted, their branch circuits will automatically be placed in a parallel connection.

As in all hydraulic systems, more pump oil will flow to the branch with the lightest load. Bank valve handles can be modulated to equalize the flow to each branch. When individual 4-way valves are used in each branch, flow control valves may be installed in the branch circuits and adjusted to give the flow desired in each branch.

Figure 2 shows a multiple branch circuit in which a variable displacement pump is used to advantage. Individual 4-way valves, solenoid operated, are used for each branch, and they have closed center porting. Please refer to Design Data Sheet 54 for possible drift problems on a pressure manifold system. A pressure relief valve is usually required even with a pressure compensated pump due to the time interval required for the swash plate to reduce its tilt angle when a sudden overload occurs. The relief valve will help absorb part of the pressure spike generated during this brief interval. It should be adjusted to crack at about 500 PSI higher than the pressure adjustment of the compensator piston spring to prevent oil discharge across it during normal operation.

All hydrostatic transmission systems use a variable displacement pump with pressure compensator, and often combine the compensator with other controls such as the horsepower input limiter, load sensing, flow sensing, or constant flow control.

Functions: Cylinder piston “return”, “hold”, “controlled advance” (pressure compensated) and “advance” (full flow). Will deliver a relatively constant flow regardless of pressure between 1000 and 10000 psi.

Used on these pumps: PA17, PA46, PA55, PE17, PE21, PE30 (Adapter kit 252161 is required for mounting this valve to a PE30 or PG30 series pump.), PE46, PE55, PE90, PE200, PE400, PG30 (Adapter kit 252161 is required for mounting this valve to a PE30 or PG30 series pump.), PG55, PG120, PG400, PQ60 and PQ120 series.

We are a recognized trader and authorised dealers "Dowty" of a wide range of Dowty Gear Pumps. Our products are acknowledged for their attributes like easy installation, low power consumption, light weight, minimum maintenance, corrosion resistance, perfect finish and durability. Owing to these features, our products are used in automotive & defence sectors and agricultural equipment & construction equipment industries. Further, the gear pumps are used in hydraulic applications.

We are engaged in offering a comprehensive range of Gear Pumps to the clients. Our customers can avail these products in different specifications from us.

Owing to our years of experience, we are able to offer a wide array of Gear Pumpsto the customers. The products offered by us are in strict compliance with the global quality standards. We offer these products in various specifications to our clients, spread across the globe.

Dynamatic®has a completerange of gear pumps for bothmobile and industrial marketsegments. Dynamatic®developed these pumps intechnical collaboration withDOWTY Hydraulic unitsLimited, U.K.

Pumps are also available inTandem Configurations and thecompany specializes insupplying units to special orderinstructions (subject toquantity) including multiplesection pumps.

We are instrumental in offering a wide array of Gear Pumps to the clients. These products are available in varied wattages and other specifications in the worldwide market.

Hydraulic systems are safer and easier to control than traditional motors. However, any machine can have issues. For instance, what should you do if the shaft seal fails on a pressure compensated pump?

A pressure compensated pump is a complex type of pump. For simpler pumps, turning it 360° will always release the same amount of oil. With a pressure compensated pump, however, the flow is adjustable. Sometimes it will release a certain amount, sometimes a different amount.

A pressure compensator is a device built into some pumps. It automatically reduces (or stops) pump flow if system pressure rises above a preset maximum (sometimes called the “firing” pressure). The compensator prevents the pump from being overloaded.

Most hydraulic industrial equipment is designed to work at about 2,000-3,000 PSI (pounds of pressure per square inch). There are two main ways a system can fail: having too little pressure or having too much.

When most pumps fail, pressure drops as fluid leaks out. But when pressure compensated pumps fail, they fail high. They build up too much pressure. This can cause many problems including shaft seal failures, where the shaft seal comes off and slings oil everywhere.

Such accidents are extremely rare, but it’s good to be prepared. A relief valve on your hydraulic system will prevent the pressure from building up too much. The valve will return liquid to the tank when there’s too much in the system. This will not only prevent your shaft seal from coming loose but will protect your whole system from a catastrophic failure.

When hydraulic industrial equipment fails, you can lose a lot of time and productivity waiting for repairs. Our certified team will come to you, performing on-site troubleshooting to minimize downtime and get your equipment running.

Multiple planter systems are typically controlled using the main tractor directional valve. The tractor pump usually operates at max pressure during planting creating:

By using a dedicated pressure-compensated pump driven by the tractor’s PTO to power the planter hydraulic downforce system, the tendency for the tractor pump to operate at high-pressure standby is reduced, thereby reducing a major contributor to excess heating and poor fuel consumption. The pump should be low displacement and sized to handle downforce flow needs. The pump also provides supply pressure to operate the Power Beyond pump.

The pump has a secondary function by providing a pressure source for a proportional pressure control valve which can be intelligently controlled via the tractor power beyond load dense port.

By intelligently controlling a tractor pump by using the tractor"s power beyond option, the planter has complete control of the pump providing the freedom to design and control the planter as desired. Pressure sensors at the fan and fertilizers functions allow for intelligent electric load sense, removing the need for additional hoses.

By separating the hydraulic downforce from the other planter functions, the tractor and planter power usage is optimized, reducing heat and therefore improving overall efficiency and component life. By controlling the tractor pump directly the planter is free to control the fan, fertilizer, and other accessory functions more intelligently.

The P1M-28 is a low displacement pump that is ideal for providing only the flow needed for downforce systems at the pressure required. The P1M Series delivers higher speeds and efficiency that increase machine productivity, reduce costs, and extend pump life in a robust, compact envelope.

Parker’s EPR series of valves is an ideal valve choice when Intelligently controlling load sense systems for hydraulic devices up to 285 bar (4,000 psi).

The EPR valve’s market-leading performance features the capability to handle flow rates up to 60 pm (15 GPM) and can control pressures as high as 285 bar (4,000 psi). For systems with pressures less than 70 bar (1,000 psi), a slip-in style is available, otherwise, a threaded screw-in style connection is available for systems with pressure in excess of 70 bar (1,000 psi), making the EPR a versatile addition for numerous applications.

The Parker Global Mobile Systems engineering team and Hydraulic Pump and Power Systems Division"s application engineering experts are available to assist our customers in designing and implementing new systems to meet your application needs.

Pressure compensation is the control of flow by compensating for the changes in load pressure. Most hydraulic systems today use pre-compensation as a means of maintaining consistent flow from an orifice or spool. However, there are applications when post-compensation has advantages over pre-compensation.

The fundamental difference is that with pre-compensation, the pressure drop across the orifice or spools is determined by the compensator. With post-compensation, the pressure drop is determined by the load sense (LS) spring inside the pump.

In post-compensated systems with multiple functions, the pump flow is divided at a fixed ratio. If flow settings exceed the pump output capability, the flow is reduced to each function at a fixed ratio. This is why post-compensation is sometimes referred to as “flow sharing”.

In post-compensated circuits, the pressure drop across each valve is determined by the load sense spring in the pump and all valves or orifices will have the same pressure drop. The load sense differential, sometimes referred to as standby, decreases when the pump cannot satisfy the total demand. All pressure compensators reference the highest load of the various functions.

The benefits include high efficiency under partial load and/or partial speed conditions and all functions slow down together at a fixed ratio when the pump cannot fully satisfy demand.

In the example below, the pump differential, or standby, is 200 PSI. The load sense pump will develop enough pressure to overcome the load and maintain a 200 PSI differential. The pressure drop across the valve or orifice remains fixed and is calculated by: system pressure minus the highest load pressure minus the compensator spring value.

The circuit below is an example of the flow sharing aspect. When another function is operated and the pump cannot fully satisfy the flow demand, the differential decreases. The pressure drop across each valve or orifice is reduced at the same fixed ratio, so the flow is divided, or shared, equally. In this example, each valve is fully open so total pump flow is shared equally between the functions.

So what happens when the functions require different flows and the pump cannot fully satisfy the total flow demand? The pump flow will be divided into the ratio of each function to total flow available. In the example below, the theoretical total flow demand is 42 GPM. The ratio of the function flow demand to total theoretical flow demand multiplied by the maximum pump flow is the resulting actual flow from each valve.

Post-compensation will increase stability and control in systems where demand can exceed the pump’s flow output. Because of its increased efficiency under partial load conditions, the compensator saves horsepower and reduces heat. It will also make the initial movement of actuators more predictable and provide better operator control.

We take pride ourselves in offering a superior range of Pressure Compensated Load Sensing Valveswhich is provided using best grade raw materials that are sourced from reliable entities. Our range of Load Sensing Valve is highly tested for their efficiency, reliability and for their high performance. We use latest technologies to meet the specifications of the clients. Clients can avail these valves at competitive prices.