Relief Valves
Symbol
Cross Section
Cavity Details
152
Technical Features
VH043
METRIC Cartridge - 420 bar
Direct acting - Poppet type
RVD0.M20 Valve Series
All external surfaces are zinc plated and corro-
sion-proof. All valve parts are made of high strength
steel. Poppet is hardened and ground to guarantee
minimal wear and to extend service life. Adjustment
screw cannot be backed out of the valve. Optional
spring ranges to 420 bar (6000 psi). Metric cavity.
A screw-in, cartridge style, direct acting, poppet type,
normally closed hydraulic relief valve. It’s typically
used to protect hydraulic components from pressure
transients. When the pressure at the Inlet (1) reaches
the valve setting, the valve starts to open to tank (2)
throttling flow to minimize the pressure rise. The in-
novative geometry of the deflector provides in fact a
very low rise rate, and the poppet design guarantees
great stability. The cartridge offers quick response to
load changes in hydraulic circuits requiring low inter-
nal leakage as well as limited hysteresis.
Description
Technical Data
153
Specications may change without notice.
Ordering Code
Maximum operating pressure 420 bar
Maximum flow 30 l/min
Setting Pressure See table below
Maximum internal leakage 1 cm
3
/min to 80% of nominal set point
External component treatment
Zn/Fe - standard (96h)
Zn/Ni (720h)
O-ring Temperature Range -30° C to 110° C (standard sealing NBR - BUNA-N)
Oil Temperature Range -30° C to 110° C
Pressure settings established @5 l/min
Reseat pressure nominal 85% of cracking pressure
Fluids Mineral - based or synthetics with lubricating properties
Viscosities 7,4 to 420 cSt
Filtration 20/18/15 ISO 4406 (maximum ltration admitted)
Orientation No restrictions
Installation torque 45-50 Nm (Hex. 22)
Tightening torque nut 20-25 Nm (Hex. 17)
Technical specications for characterization See page 480
Oil testing condition ISO VG 46 cSt
Seal kit code SK.020
Weight 0,145 kg
Relief Valves
Springs’ Graphs
154
Spring = Y (5 - 55 bar)
RVD0.M20 Valve Series
1
2
p/Q performance
p/Q performance
Flow (l/min)
Flow (l/min)
Pressure (bar)
Pressure (bar)
Spring = N (25 - 110 bar)
Note: The performance chart illustrates flow handling capacity for each
spring bias options. p/Q curves are recorded at TOil = 40°C and 46 cSt
155
Specications may change without notice.
4
5
p/Q performance
Flow (l/min)
Pressure (bar)
3
Spring = G (100 - 350bar)
Spring = V (100 - 420bar)
Spring = B (50- 215bar)
p/Q performance
p/Q performance
Flow (l/min)
Flow (l/min)
Pressure (bar)
Pressure (bar)
