Kalmar DCE80-100E, Technical Handbook

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DCE80-100E
Technical Handbook
Main hydraulics
Description
12 P. Group 70
TDCE01
04GB
Lowering brake valve
The lowering brake valves are screwed into the connecting pipes
at the bottom of the cylinders. They are preset and no adjustment
facilities are provided.
The valve contains a spring-loaded control plunger and a mova-
ble orifice plate, both of which interact to provide a constant flow
through the valve regardless of the prevailing load.
During lifting, the orifice plate and the control plunger are in a po-
sition which allows unrestricted flow of fluid. During lowering, the
orifice plate moves to the throttling position. The internal pressure
drop in the valve and the pre-load force of the control plunger
spring counteract one another and set the control plunger in an
equilibrium position, ie. in relation to the corresponding size of
the throttle gap. Large load – small gap, small load – large gap.
.
Lowering brake valve
1. Control plunger
2. Throttling slot
3. Orifice plate in the throttling position
4. Orifice plate in the open position
4
2 3
1