TM 9-4940-568-20
5-8
5-3.
DESCRIPTION AND DATA (Continued)
(5) DOUBLE HOLDING VALVE. The
double holding valve prevents
movement of the mast erection cylinder
in either direction until its preset safety
pressure is overcome by hydraulic
pressure from operation of the crane’s
control in the opposite direction.
(6) SINGLE HOLDING VALVE. The single
holding valve prevents movement in
one direction until its preset safety
pressure is overcome by hydraulic
pressure from operation of the crane’s
controls.
(7) MAIN RELIEF VALVE. The main relief
valve protects the crane’s components
from pressures that might exceed 3,500
psi.
(8) HOIST PRESSURE RELIEF VALVE.
The hoist pressure relief valve limits
pressure to 2500 psi in the HOIST UP
circuit.
MAIN RELIEF
VALVE
HOIST RELIEF
VALVE
DOUBLE
HOLDING
VALVE
SINGLE HOLDING
VALVE
SINGLE
HOLDING
VALVE
