Two boom cylinders are used to RAISE and LOWER the boom. When the boom cylinder rods EXTEND, the boom RAISES. When the boom cylinder rods RETRACT, the boom LOWERS.
The main hydraulic pumps supply high-pressure oil to the main control valve. The main hydraulic control valve determines the direction and speed of the boom cylinders in proportion to the movement of the joystick. A BOOM RAISE operation is accomplished when the oil delivery from both idler pump and drive pump is supplied to the head end of boom cylinders . Flow combiner proportional hydraulic modulation valve (PHMV) is activated by the machine ECM. Flow combiner spool then shifts to the allowing idler pump oil to combine with drive pump oil. The combined oil from the idler pump and the drive pump then flows to boom Independent metering valve (IMV) section.
Components of the boom system include:
- Boom IMV section
- Boom regeneration valve
- Boom cylinders
Note: Refer to the appropriate sections in this manual for more information.