Danfoss PVG 32, Техническая информация

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PVMR, friction detent
The friction detent PVMR allows the directional spool to
be held in any position, resulting in infinitely variable,
reversible, pressure compensated flow.
This can be sustained indefinitely without having to
continue to hold the mechanical lever.
Friction detent spool position may be affected by high
differential actuator flow forces and system vibration
resulting in work function flow reduction.
PVMR, friction detent
PVMF, mechanical float position lock
Allows the float spool to be held in the float position after release of the mechanical handle.
PVMF, standard mount only
P
→
A
→
F (Push-in)
PVMF, optional mount only
P
→
A
→
F (Pull-out)
PVBS, main spools for flow control (standard)
When using standard flow control spools, the pump pressure is determined by the highest load pressure.
This is done either via the pressure adjustment spool in open center PVP (fixed displacement pumps) or
via the pump control (variable displacement pumps).
In this way the pump pressure will always correspond to the load pressure plus the stand-by pressure of
the pressure adjustment spool or the pump control. This will normally give optimum and stable
adjustment of the oil flow.
PVBS, main spools for flow control (linear characteristic)
PVBS main spools with linear characteristic have less dead band than standard spools and a proportional
ratio between control signal and oil flow in the range beyond the dead band. PVBS with linear
characteristic must never be used together with PVEM electrical actuators.
The interaction between the small dead band of the spools and the hysteresis of the PVEM actuator of
20% involves a risk of building up a LS pressure in neutral position.
Technical Information
PVG 32 Proportional Valve Group
Function
© Danfoss | August 2017 520L0344 | BC00000038en-US0802 | 21