TURN-CONTROL DEVICE OF HYDRAULIC SHOVEL

摘要

PROBLEM TO BE SOLVED: To install a variable relief valve by effectively utilizing an existing space. SOLUTION: The relief valves 9 and 9 in an optional valve block C installed on the outer surface side of a main valve block B including a turn-control valve 11 are formed as variable relief valves switchable to a high pressure or low pressure, and connected to a turn motor circuit A so as to be used as the relief valves for lowering a turn motor pressure.