Komatsu PC600LC-7 Manual page 153

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD
1. At boom RAISE
Operation
• When the boom is raised, the main pressure
from the control valve pushes poppet (5) up.
Because of this, the main pressure from the
control valve passes through the valve and
flows to the bottom end of the boom cylinder.
PC600, 600LC-7
BOOM HOLDING VALVE
10-121