METHOD FOR REPAIRS OF SPOOLS OF TRACTOR HYDRAULIC CONTROL SYSTEMS Russian patent published in 1994 - IPC

FIELD: repair practice. SUBSTANCE: method involves boring out the spool seat without driving it out, over the inner hole to a larger repair size, cutting off spool head with conical closing element until a cylindrical surface is formed on which a bush with radial drain channels is pressed. Bush is ground to the spool seat opening, ensuring a minimum clearance in the joint, and secured on valve by radial pin while the piston part of spool is ground to repair size and the throttle hole is plugged. EFFECT: higher efficiency. 4 dwg