METHOD FOR END PREPARATION OF OIL GRADE PIPES FOR THREAD CUTTING

摘要

FIELD: metallurgy.SUBSTANCE: method involves press deformation. The uniform passing ability of the inner surface of a pipe and a coupling in a thread connection is provided due to the fact that at deformation the pipe length is provided on the length of 10-35 mm from the end face in the pipe body direction with the shape of a flattened cone with a smaller base diameter that is by 2-10 mm smaller than that of the outer pipe diameter and with a larger base diameter equal to the outer diameter of the pipe so that the initial wall thickness is maintained. Application of the method is possible both after preliminary heat treatment is performed and without it.EFFECT: obtained configuration of the pipe end provides for a possibility of cutting a thread with sealing and stabilising surfaces and boring of the pipe as to the inner diameter; obtaining the thread of specified parameters; reducing the labour input of the process.1 dwg