EP 0124026 A3 19850320 - A METHOD OF FORMING RIBS IN BIMETALLIC TUBES AND A RIBBED TUBE FORMED BY THE METHOD
Title (en)
A METHOD OF FORMING RIBS IN BIMETALLIC TUBES AND A RIBBED TUBE FORMED BY THE METHOD
Publication
Application
Priority
PL 24162383 A 19830423
Abstract (en)
[origin: EP0124026A2] A method of forming ribs on bimetallic tubes, in which initial compressive stress is introduced in the external tube (2), the roughness of the ends of the internal tubes (1) is increased, and after placing the internal tube (1) in the external tube (2), the ends of the external tube are clamped on segments (3, 4) of the internal tube (1) of increased roughness with simultaneous axial displacement of a part of the material of the external tube of a quantity adequate to introduce comressive stresses of a required quantity. In the tube thus prepared ribs are formed. It is preferable if at least one end of the external tube (2) is formed conically during clamping.
IPC 1-7
IPC 8 full level
B21C 37/26 (2006.01); B21C 37/06 (2006.01); B21C 37/20 (2006.01); B21C 37/22 (2006.01); B21D 39/04 (2006.01); B21D 53/06 (2006.01); B23K 20/04 (2006.01)
CPC (source: EP)
B21C 37/06 (2013.01); B21C 37/20 (2013.01); B21C 37/22 (2013.01); B21D 39/04 (2013.01)
Citation (search report)
- [A] FR 932059 A 19480311
- [A] DE 1452518 A1 19690529 - VNI I P KI METALL MASH
- [A] DE 1295333 B 19690514 - HOWELL AND COMPANY LTD
Designated contracting state (EPC)
DE FR GB IT NL SE
DOCDB simple family (publication)
EP 0124026 A2 19841107; EP 0124026 A3 19850320; EP 0124026 B1 19881012; CS 249134 B2 19870312; DE 3474525 D1 19881117; HU 191559 B 19870330; HU T38273 A 19860528; PL 139850 B1 19870228; PL 241623 A1 19841108; RO 91020 A 19870930; RO 91020 B 19871001; SU 1428184 A3 19880930
DOCDB simple family (application)
EP 84104413 A 19840418; CS 292984 A 19840418; DE 3474525 T 19840418; HU 150084 A 19840418; PL 24162383 A 19830423; RO 11430884 A 19840418; SU 3725407 A 19840417