PURPOSE: To accomplish a desired quenching effect with a simple apparatus, in quenching a cylindrical part, by cooling the inner and outer surfaces of the heated cylindrical part with the whirlpool and spray of cooling water.
CONSTITUTION: A cylindrical part 1 whose inner and outer surfaces are heated at a high temperature for quench-hardening them is supported with a supporting piece 6 inside a cylindrical jacket 4 provided with many cooling water-spraying holes 4a at its inner surface, and mounted on a work stand 3 arranged on the main body 2 of a nozzle. Cooling water forcedly poured through a water-supply pipe 5 into the cylindrical jacket 4 is sprayed through the spraying holes 4a to the outer surface of the part 1 to rapidly cool and quench it. At the same time, cooling water forcedly poured through a water-supply pipe 12 is let flow through a whirlpool pipe 8 provided with a screw 8a and discharged as a turning current through the opened part 2a of the nozzle to the inner surface of the part 1, to rapidly cool and quench the inner surface of the part 1. In this way, the inner and outer surfaces of the cylindrical part are uniformly quench-hardened without the need to spray cooling water with a special high-pressure means.
TAKAYAMA TAKEMORI
URANO HIDETAKA
NITSUTA KAZUYUKI
OOKAWA KAZUHIDE
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