Direct Acting Pressure Reducing Relieving Valves

Parker's selection of direct acting reducing & relieving valves provide superior pressure control in applications where specific regulated and relief pressures are needed for precise operation on functions that require regulated pressures up to 420 bar (6000 psi) and flows up to 56 lpm (13 gpm). Parker's direct acting reducing & relieving valves are designed with several pressure ranges in order to give a higher degree of control with a variety of adjustment style options available. The wide array of options and settings make these valves ideal for sensitive applications such as up or downforce, clamping, or braking on various types of machinery within the mobile and industrial markets.

Markets:
• Agriculture
• Construction Equipment
• Industrial
• Miscellaneous Manufacturing
• Miscellaneous Mobile

Features/Benefits:
• Multiple pressure ranges available for more accurate pressure control
• Adjustable and tamperproof versions available
• High flow capacity
• All external parts zinc plated

Applications:
• Brakes
• Clamps
• Suspension systems
• Up/down-force systems

Additional Technical Insight:
Direct Acting Reducing/Relieving valves are applied in a circuit in order to reduce system pressure to the setting of valve to limit the pressure available to a specific branch of a hydraulic circuit. The direct acting function of the normally open valve allows the spool to operate directly against a control spring that is set using the valves internal adjustment setting. As hydraulic pressure is applied to the valve inlet, the spool will shift closed against the spring to limit the pressure that is available to the regulated port to the control setting. The valve will also function as a relief valve to the regulated port in the event of a rise in downstream pressure, protecting the regulated branch of the circuit from pressure spikes. Direct acting reducing/relieving valves are intended or intermittent duty applications with lower duty cycles that will not stress the mechanical operation of the valve. For best performance in the direct acting reducing/relieving valve, the inlet pressure setting should not exceed 1000 PSI (69 Bar) above the reducing valve setting, as high pressure differential could result in instability in the direct acting product. For continuous duty applications or applications where a high differential is required, the pilot operated version of this product should be considered as an alternative solution.

Typical applications are in mobile & industrial equipment, where a branch of the system is intended to operate at a lower setting than high system pressure.  Hydraulic functions such as brake circuits, clamping or clutch circuits, suspension systems, street sweepers, or seeding and planting rows in agricultural equipment are common applications for these products.