摘要 |
FIELD: process engineering.SUBSTANCE: invention relates to production of welded tubes. Displacing metal strip is bent by rolls to cylindrical shape to weld its ends together by welding unit. Welding unit power supply is located nearby said bent metal strip and composed of induction heater or device of heating by passing current for heating metal strip both ends. Pressure rollers weld heated strip ends together by bringing them in contact and pressing against each other. Ferromagnetic body slides between said ends and is arranged in the section of clearance along metal strip displacement and upstream thereof with respect to said power supply.EFFECT: higher efficiency of heating owing to increased magnetic field and current density.14 cl, 27 dwg, 3 tbl, 9 ex |