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POCLAIN HYDRAULICS Hydraulic components - Pressure control valves
Direct operated valvesPilot operated valves
PRESSURE RELIEF VALVE VP-RT (NG 6, 10)
• NG 6, 10
• Up to 350 bar [5 076 PSI]
• Up to 100 L/min [26.4 GPM]
• Pilot operated.
• Connecting dimensions to ISO 4401.
• For vertical stacking - sandwich plate design.
• Two pressure setting ranges.
VP-RT-10, VP-RT-6
Operation Hydraulic symbol
These valves consist of a stack plate (1), pressure relief valve housing (2), main spool
insert (3) with a spring (4), pilot poppet (5), spring (6) and pressure setting element (7).
The P-line of this pressure relief valve is connected with the hydraulic system. The
hydraulic medium pressure acts on the front side of the main spool insert (3). The bores
(8,9) permit the introduction of pilot oil into the pressure chamber (10) and the application
of pressure to the opposite side of the main spool insert.
This pressure relief valve remains in closed position till the system pressure exceeds the
valve set at the spring (6). A pressure rise in the system above the value set by the
pressure setting element (7), provokes the movement of the pilot poppet (5) of the seat,
freeing the pilot oil discharge through the bores (9) and (11). A pressure drop in the
pressure chamber (10) rises the main spool insert (3), thus clearing the hydraulic medium
flow in the direction from port P towards port T.
Loosening of the pressure setting element is prevented by a counternut (12).
Pilot operated pressure relief valves type VP-RT of sandwich plate design, for vertical
stacking, are used for maintaining and limiting the maximum pressure in a hydraulic
system.
Features
Size 6 10
Flow rate L/min [GPM] 50 [13.2] 100 [26.4]
Pressure setting range bar [PSI]
To 315 [4 568]
Oil temperature range °C [°F]
-20 to +70 [-4 to +158]
Viscosity range mm
2
/s [SUS]
15 to 380 [69.5 to 1 760]
Filtration NAS 1638
8
Mass Kg [lb] 1,2 [2.64] - 1,7 [3.75] (D) 2,6 [5.73]