Direct Acting Relief Valve


Pressure Relief valves are used to limit the pressure in the system as set on the valve. Direct Relief Valves are applicable in systems where quick pressure release is of prime concern for safety. This is an economical solution for systems having moderately large flows. The valve is a zero leak valve due to the metal sealing of the poppet on the seat.


As with all direct acting pressure relief valves, when the pressure at the inlet (P) exceeds the spring force set by the adjuster, the poppet moves back, opening the inlet (1) to outlet (T). This relieves the pressure to tank. The dampening buffer on the nose of the valve dampens the vibrations caused by pressure variations on the valve.This gives it a smooth opening and closing characteristic with minimum chatter.


Matched ground and hardened working parts give a long and troubleGfree life. Consistent stable operation providing low pressure over ride even with increasing flows. Cartridge type construction gives maximum flexibility in mounting.


Figures based on: Oil Temp = 40°C Viscosity = 40 cSt

Rated Flow 160 lpm
Max Pressure 350 bar
Cartridge Material Working parts : Hardened, ground steel
External surfaces : Zinc plated
Weight (Cartridge only) DR20: 0.680 kg
Cavity Number CDR20 (Refer Cavities Section)
Manifold Material SG Iron (upto 350 bar)
Torque into Cavity 100 Nm
Mounting Line
Seal Kit Number SKDR20 (Nitrile) SKDR20V (Viton®)
Filtration Level BS5540/4 Class 18/13 (25F nominal)
Operating Temp -20°C to +90°C (Standard Seals)
Leakage Less than 0.3 millilitres/min (5 dpm)
Viscosity Range 5 to 500 cSt