Komatsu PC200-8M0 Shop Manual page 165

402 Hydraulic system, Part 2
Functions and operation by valve
Pressure compensation valve
When the work equipment is operated independently and the load pressure is the maximum
(When the load pressure is higher than other work equipment during a combined operation)
1. Main pump
2. Valve
3. 3.Shuttle valve
Function
Pressure compensation valve works as the
q
load check valve.
q If the pump pressure (LS pressure) is lower
than the load pressure at port (c), shuttle valve
(3) in pressure compensation valve piston (4)
interconnects spring chamber (E) and port (C).
q The force of spring (5) operates piston (4) and
valve (2) to the closing direction.
Integrated pressure compensation valve
q When a high peak pressure or continuous and
repetitive peak pressure (as in breaker opera-
tion) is generated in the actuator circuit, valve
(2) may collide with valve chamber seat (C),
producing high stress in the parts.
q To prevent this, a pressure compensation
valve with integrated valve (2) and piston (4) is
used.
q With this machine, this valve is adopted for the
travel valve, bucket valve (cylinder bottom),
and the service valve.
PC200, 200LC, 220, 220LC-8M0
4. Piston
5. Spring
6. LS shuttle valve
SEN06120-00
23
10-402