Created on 03/17/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 1 of 2
MODEL
PVHA8
Pilot operated, pressure reducing/relieving main stage with integral T-8A control
cavity and drain to port 4
SERIES 3 / CAPACITY: 160 L/min. / CAVITY: T-23A
This valve is a 3-way, normally open modulating element, externally drained, that incorporates an integral pilot
control cavity. The pilot control cavity will accept any T-8A pressure control cartridge. The valve reduces a high
primary pressure at the inlet (port 2) to a constant reduced pressure at port 1, with a full flow relief function from port
1 to tank (port 3). The pilot cartridge's setting determines the difference in pressure between reduced pressure (port
1) and the drain (port 4).
TECHNICAL DATA
Maximum Operating Pressure 350 bar
Control Pilot Flow 0,25 - 0,33 L/min.
Pilot Control Cavity T-8A
Pilot Control Valve Installation Torque 27 - 34 Nm
Pilot Control Valve Hex Size 22,2 mm
Seal kit - Cartridge Buna: 990-023-007
Seal kit - Cartridge Polyurethane: 990-023-002
Seal kit - Cartridge Viton: 990-023-006
(W)MINIMUM CONTROL PRESSURE
W 100 psi (7 bar)
D 25 psi (1,7 bar)
(N)SEAL MATERIAL
N Buna-N
V Viton
snhy.com/PVHA8
TECHNICAL FEATURES
Maximum pressure at port 3 should be limited to 3000 psi (210 bar).
Pilot operated valves exhibit very low dead-band transition between reducing and relieving modes.
Pressure at port 4 should not exceed 5000 psi (350 bar).
Pilot operated valves exhibit exceptionally flat pressure/flow characteristics, are very stable and have low hysteresis.
Pressure on the drain (port 4) is directly additive to the valve setting at a 1:1 ratio and should not exceed 5000 psi (350 bar).
Compound cartridge (pilot and main stage) assembly information is provided for reference only. Cartridges must be ordered separately and assembled at
point of use.
NOTES
Model Code Example: PVHA8WNCONFIGURATION OPTIONS
Created on 03/17/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 2 of 2
Maximum inlet pressure is determined by the bias spring. The D spring is tested with 2000 psi (140 bar) maximum differential pressure and the W spring is tested
with 5000 psi (350 bar) maximum inlet pressure.
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.
Full reverse flow from reduced pressure (port 1) to inlet (port 2) may cause the main spool to close. If reverse free flow is required in the circuit, consider adding a
separate check valve to the circuit.
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.
PERFORMANCE CURVES
RELATED MODELS
PVHA Pilot operated, pressure reducing/relieving valve with drain to port 4
