Relief assembly with reverse flow check


Function for YREJ
Port Designators [ + ]
Modifiers Ports
C, C/S Ports A, B, P, T: 1/2" NPTF; Gage Port: 1/4" NPTF;
K, K/S Ports A, B, P, T: SAE 10; Gage Port: 1/4" NPTF;
V, V/S Ports A, B, P, T: 1/2" BSPP; Gage Port: 1/4" BSPP;
Technical Features [ + ]

This assembly consists of a 30 PSI check and a pilot-operated, balanced-piston relief cartridge which is a normally closed pressure regulating valve. When the pressure at the inlet (P port) reaches the valve setting, the valve starts to open to tank (T port), throttling flow to regulate the pressure. These valves are accurate, have low pressure rise vs. flow, they are smooth and quiet, and are moderately fast.

  • 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.
Technical Data [ + ]
Body Type SubplateSubplate
Interface ISO 05ISO 05
Capacity 25 gpm95 L/min.
Check Cracking Pressure 30 psi2 bar
Body Features P to T, check on P, side portsP to T, check on P, side ports
Stack Height 1.94 in.49 mm
Mounting Hole Diameter .44 in.11.1 mm
Mounting Hole Quantity 44
FAQs [ + ]

There are exactly 250 Sun drops in a cubic inch or 15 in a cc.

Direct-acting valves are used to prevent over pressure, and pilot-operated valves are used to regulate pressure. If you are unsure, use a direct-acting valve. Sun's direct acting valves are very fast, dirt tolerant, stable, and robust. Sun's pilot-operated valves are moderately fast, they have a low pressure rise vs. flow curve, and they are easy to adjust.

Notes [ + ]
  • Important: Carefully consider the maximum system pressure. The pressure rating of the manifold is dependent on the manifold material, with the port type/size a secondary consideration. Manifolds constructed of aluminum are not rated for pressures higher than 3000 psi (210 bar), regardless of the port type/size specified.
Additional Resources [ + ]