| 摘要 |
PURPOSE: A hydraulic control valve device for construction equipment is provided to prevent abrasion due to the contact friction between a spool and a valve body while relieving operational impact when the spool lifts up and down. CONSTITUTION: A hydraulic control valve for construction equipment comprises a valve body(100), a hydraulic operational mechanism(110), and a spool(120). Multiple operational impact absorbing grooves are radially formed at a same interval on the top of the inner diameter of a first spool seat end of the valve body corresponding to the external diameter of a first diameter part(123) of the spool. A foreign material removing unit for removing metal foreign materials contained in hydraulic oil is installed in a hydraulic inlet path(102) and a hydraulic outlet path(103) of the valve body. In order to make a metal push rod(112) connected to the upper part of the spool and a pushing cam(113) pushed by the push rod, case nodular iron is melted at 1400-1600°C and is desulfurized. A spheroidizing agent containing 0.2-0.8% of magnesium is added in the desulfurized case nodular iron. [Reference numerals] (AA) High-frequency heat treatment; (BB) Hydraulic motor and hydraulic cylinder; (CC) Hydraulic pump |
