VH Series pressure controls are ideal
for use in high pressure and high
shock systems. These pilot-operated
poppet style
valves provide fast
response to circuit conditions.
Relief
valves regulate pressure and
provide circuit protection at pressures
to 15 000 psi (1040 bar).
Unloading
valves divert pump output
to tank in response to pilot pressure
signal.
Decompression
valves reduce flow
surges in high pressure systems.
Excess flow is metered to tank, in
response to an electrical or
pressure signal to the
valve control.
High transient flows in a circuit when
a cylinder is reversed, for example,
can cause directional
valves not to
shift. Metering the excess flow to tank
before shifting the directional control
valve prevents this problem.
These
valves also reduce system
decompression vibration and noise.
SIMPLIFIED CIRCUIT CONTROL
Models with optional vent control can
be remotely actuated by an external
signal. These
valves use an integral
Dynex VSTV seated control
valve
with solenoid, air or hydraulic
actuator.
See “Valve Operation and Venting
Functions” on page 2.
SUITABLE FOR SPECIAL FLUIDS
These
valves can be used with some
water-based, fire-resistant and other
special fluids.
The properties of these special fluids
include a combination of high or low
viscosity with either high or low
lubricity. They include water glycol,
various military fluids, Skydrol and
other phosphate ester fluids.
Contact the Dynex sales department
for complete information.
High Pressure Relief, Unloading
And Decompression Valves
VH SERIES
30 gpm (114 L/min)
7000 to 15 000 psi (490 to 1040 bar)
High Pressure Hydraulics DYNEX ENGINEERING
SPECIFICATIONS
Subplate Mounted VH Series Relief Valve with Electric Vent Option
HIGH PRESSURE APPLICATIONS
High pressure capability and
compatibility with special fluids make
these
valves ideal for use in metal
processing hydrostatic lube or roll
balance systems.
They are also well suited for development
or production test-stands,
aircraft ground support equipment,
Hydroforming and other hydraulic
presses, and other demanding
applications.
SPECIFICATIONS
Rated Pressure
Model VHR Relief Valves:
Maximum 10 000 psi (700 bar) or
15 000 psi (1040 bar);
Model VHU Unloading Valves:
Maximum 7000 psi (490 bar) or
10 000 psi (700 bar), with pilot
unloading pressure to 15 000 psi
(1040 bar);
Model VHD Decompression Valves:
Maximum 10 000 psi (700 bar) or
15 000 psi (1040 bar);
Maximum Drain Port Pressure
(Optional Electric Vent)
Standard:
1000 psi (70 bar) dynamic,
3000 psi (210 bar) static;
High Pressure Drain “D” Option;
refer to model code, page 4:
3000 psi (210 bar) dynamic,
5000 psi (350 bar) static;
Rated Flow
Model VHR Relief and
Model VHU Unloading Valves:
15 gpm (57 L/min) nominal,
30 gpm (114 L/min) maximum;
Model VHD Decompression Valves:
25 gpm (95 L/min) nominal,
30 gpm (114 L/min) maximum
Valve Adjustments
On relief or unloading
valves,
pressure is preset by turning the
knurled knob adjustment clockwise to
increase pressure.
On decompression
valves, turning
the internal hex adjustment
counter-clockwise increases the flow
rate metered to tank.
