Model

RPGC8WN

Adjustment Range
Seal Material

Model: RPGC8

Pilot-operated, balanced piston relief main stage with integral T-8A control cavity

Cavity: T-3A | Capacity:

Model

RPGC8WN

Adjustment Range
Seal Material

Technical specifications

This valve is a normally closed modulating element that incorporates an integral pilot control cavity. It is a balanced piston design. The pilot control cavity will accept any T-8A pressure control cartridge. When the pressure at the inlet (port 1) reaches the pilot control cartridge's setting, the modulating element starts to open to tank (port 2), throttling flow to regulate the pressure. The pilot cartridge's setting determines the difference in pressure between port 1 and port 2.

  • All 2-port relief cartridges (except pilot reliefs) are physically and functionally interchangeable (same flow path, same cavity for a given frame size).
  • Will accept maximum pressure at port 2; suitable for use in cross port relief circuits.
  • Main stage orifice is protected by a 150-micron stainless steel screen.
  • Not suitable for use in load holding applications due to spool leakage.
  • Back pressure on the tank port (port 2) is directly additive to the valve setting at a 1:1 ratio.
  • NOTE: With the -8 control option, the main stage valve should first be installed to the correct torque value. The T-8A pilot control valve should then be installed into the main stage valve to its required torque value.
  • The -8 control option allows the pilot control valve to be incorporated directly into the end of the relief cartridge via the T-8A cavity. These pilot control cartridges are sold separately and include electro-proportional, solenoid, air pilot, and hydraulic pilot operation. See Pilot Control Cartridges.
  • Cartridges configured with EPDM seals are for use in systems with phosphate ester fluids. Exposure to petroleum based fluids, greases and lubricants will damage the seals.
  • Incorporates the Sun floating style construction to minimize the possibility of internal parts binding due to excessive installation torque and/or cavity/cartridge machining variations.
  • Cavity
  • Series
  • Capacity
    50 gpm
  • Maximum Operating Pressure
    5000 psi
  • Control Pilot Flow
    10 - 15 in³/min.
  • Main stage leakage at 110 SUS (24 cSt)
    3 in³/min.@1000 psi
  • Pilot Control Cavity
    T-8A
  • Valve Hex Size
    1 1/8 in.
  • Valve Installation Torque
    45 - 50 lbf ft
  • Model Weight
    .50 lb
  • Seal kit - Cartridge
  • Seal kit - Cartridge
  • Seal kit - Cartridge
  • Seal kit - Cartridge

Model CAD Files

Files not yet avialable. Click below to request them.

  • What parts of the Sun cartridge valve are field serviceable?
  • What are the tolerances on pressure settings for Sun's pressure control valves?
  • Where would I use a kick-down relief?
  • Can I use a kick-down relief for my system relief?
  • How big is a drop of hydraulic oil?  
  • How do I get a kick-down relief to reset?
  • Direct acting or pilot operated - what do I use?
  • Compound cartridge (pilot and main stage) assembly information is provided for reference only. Cartridges must be ordered separately and assembled at point of use.
Highlights
Technical Tips
Technical Information
  • RPGC Pilot-operated, balanced piston relief valve
  • RPGC3 Non-adjustable pilot-operated, balanced piston relief valve