Komatsu PC500LC-10R Shop Manual page 335

10 STRUCTURE AND FUNCTION
MA: From control valve (swing LEFT port)
MB: From control valve (swing RIGHT port)
1: Valve body
2: Spool (MA side)
3: Spring (MA side)
4: Plug (MA side)
Figure to explain effect
FUNCTION OF SWING MOTOR REVERSE PREVENTION VALVE
• When the swing operation is stopped, the upper structure may swing back. This is due to inertia of the
weight of the upper structure, the backlash and rigidity of the swing machinery system, or compression of
the hydraulic oil. This valve can reduce such movement.
• The valve contributes in preventing spill of load when the swing is stopped and also contributes in reducing
cycle time (enhances the positioning performance, and enables to proceed to the next work quicker).
PC500LC-10R
COMPONENT PARTS OF SWING SYSTEM
T1: To hydraulic tank
T2: To hydraulic tank
5: Spool (MB side)
6: Spring (MB side)
7: Plug (MB side)
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