Created on 09/16/2015
c
2015 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 1 of 2
MODEL
RPKT
Anti Shock, pilot operated, balanced poppet relief valve
SERIES 4 / CAPACITY: 760 L/min. / CAVITY: T-18A
Pilot-operated, anti shock relief cartridges limit maximum system pressure and also limit the rate of pressure rise.
The valve opens and then ramps closed at a constant speed, independent of settings and flows. The adjust screw
determines the maximum (relief) setting and the minimum (threshold) setting.
TECHNICAL DATA
Factory Pressure Settings Established at 15 L/min.
Maximum Operating Pressure 350 bar
Control Pilot Flow 0,16 - 0,41 L/min.
Response Time - Typical 2 ms
U.S. Patent # 6,039,070
Pressure Ramp Up Time 400 - 600 ms
Adjustment - Number of Clockwise Turns to Increase Setting 4.5
Locknut Hex Size 15 mm
Locknut Torque 9 - 10 Nm
Seal kit - Cartridge Buna: 990-318-007
Seal kit - Cartridge Viton: 990-318-006
(L)CONTROL
L Standard Screw Adjustment
C Tamper Resistant - Factory Set
(A)ADJUSTMENT RANGE
A 2000 - 3000 psi (140 - 210 bar), 2000
psi (140 bar) Standard Setting
C 4500 - 6000 psi (315 - 420 bar), 4500
psi (315 bar) Standard Setting
W 3000 - 4500 psi (210 - 315 bar), 3000
psi (210 bar) Standard Setting
(N)SEAL MATERIAL
N Buna-N
V Viton
snhy.com/
RPKT
TECHNICAL FEATURES
All 2-port relief cartridges (except pilot reliefs) are physically and functionally interchangeable (same flow path, same cavity for a given frame size).
Will accept maximum pressure at port 2; suitable for use in cross port relief circuits.
Not suitable for use in load holding applications.
When pressure at the inlet (port 1) exceeds the threshold setting, the valve opens to tank (port 2). The pilot section moves forward at a steady rate, increasing the
setting by compressing the pilot spring. Maximum setting is achieved when the pilot section reaches a mechanical stop.
Valve provides protection for pumps and motors from pressure transients due to sudden load changes, especially variable displacement pumps, since the
displacement mechanism is sometimes too slow to catch these pressure transients.
Valve provides protection for hydrostatic drives by reducing the jerk caused by sudden reversals. The valve is suitable for cross-port applications.
When used with a switching device, the valve can provide the ramp characteristic typically provided by proportional valves.
Model Code Example: RPKTLANCONFIGURATION OPTIONS
Created on 09/16/2015
c
2015 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 2 of 2
Small power units can be started against an anti shock relief to provide longer pump life.
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
