GB548970A - Improvements in or relating to methods and apparatus for heat-treating metallic tubular members - Google Patents

Abstract

548,970. Heat treating tubular members. BUDD INDUCTION HEATING, Inc. April 24, 1941, No. 5321. Convention date, May 17, 1940. [Class 72] In the heat treatment of a tubular member, heat, e.g. by electromagnetic induction is applied to an annular internal zone of the member while effecting relative movement in an axial direction between the member and the heating means, and after the applied heat has flowed to the external surface of the member quenching fluid such as oil or gases, e.g. air is applied to the external surface. Quenching fluid may be applied subsequently to the inner surface. The tube 10 is moved downwardly past an induction heater 12 and the heated tube is quenched by liquid under pressure from a nozzle 32 supplied from a chamber 28 fed by a pipe 34 and mounted on a rod 46, the nozzle being directed away from the heater 12. To assist the downward flow of the quenching liquid, gas or air under pressure is fed by a pipe 38 into a chamber 36 formed by a shield 24 and thence down between the chamber 28 and the tube 10. An internal quenching device 22 provided with annular conical jets 40, 42 is adjustably mounted upon a support 44 and fed with liquid from the pipe 41 passing through the support 18 for the heater 12. The heater and the quenching device may also be rotated. Flame heaters may be used instead of the induction heater 12. Specification 509,895, is referred to.