PRODUCTION OF TAPERED FACE PISTON RING MADE OF SINTERED ALLOY

摘要

PURPOSE:To easily produce the titled piston ring having a chamfered part at a ridge part by compacting raw material powder by using a die having a taper, upper punch having a recess and a lower punch having a projecting part and chamfering part, then sintering the molding. CONSTITUTION:The raw material powder 10 packed into the space formed by the die 6 provided with the taper 61 having the inside diameter decreasing downward, a core rod 7 and the lower punch 8 is compacted by the lower punch 8 and the upper punch 9. The projecting part 81 provided to the lower punch 8 is adapted to fit to the recess 91 provided to the upper punch 9. The fillet chamfering part 82 is attached to the corner at the bottom end in the projecting part 81 of the lower punch 8 to form the chamfered part 4 to the ridge formed at the time of molding. Such green compact is removed from the dies and is sintered. The tapered face piston ring attached with the chamfered part 4 at the ridge part formed by the joint 5 and face and the top surface of the ring is thus easily produced.