GB754907A - Improvements in methods of and apparatus for bending tubes - Google Patents

Abstract

754,907. Angular bending of tubes; drawing- dies. HUET, A. Sept. 24, 1954 [Oct. 20, 1953; Oct. 20, 1953], No. 27661/54. Classes 83 (2) and 83 (4). A tube is held to a roller or former, around which it is bent as the roller is rotated, by means engaging that part of the end of the tube adjacent the roller. A tube 1 to be bent is held to a rotatable bending roller 7 by means of a jaw 10 pivoted on a bracket 9, secured to the roller 7, and engaging the inside of the tube adjacent the roller 7. The end of the tube engaged by the jaw 10 is surrounded and supported by elements 5, 6 secured to the roller 7, the part of the element 6 engaging the lower outside part of the tube end and opposing the head 12 of the jaw 10 being roughened at 8, the head 12 also being formed with roughened tube-engaging portions 13, 14, Fig. 5. The jaw 10 is pivoted to clamp the tube by a jack 15 and linkage means 17. In operation, with the tube 1 with a shaping plug 24 therein clamped to the roller 7, the roller is rotated to pull the tube through a support 20, 21, over a burner 22, under a roller 27 and around the roller 7, which rollers 7, 27 may be internally cooled. The tube 1 may be given an oval cross-section over at least part of its length, e.g. from L to M, Fig. 6, before bending and be passed over the roller 7 with the long axis of the oval in the plane of the roller, the support 20, 21 being in two parts, Fig. 8 (not shown), defining a groove of oval section throughout most of its length but of a section which can guide both the oval and the circular part of the tube at its end away from the roller 7. The parts 20, 21 of the support may define a groove changing from circular to oval crosssection so that as the tube is drawn therethrough by rotation of the bending roller 7 it is formed with an oval cross-section.