EP 1427866 B1 20051123 - METHOD FOR MAKING ROLLED AND WELDED TUBES COMPRISING A FINAL DRAWING OR HYDROFORMING STEP AND RESULTING ROLLED TUBE
Title (en)
METHOD FOR MAKING ROLLED AND WELDED TUBES COMPRISING A FINAL DRAWING OR HYDROFORMING STEP AND RESULTING ROLLED TUBE
Title (de)
VERFAHREN ZUR HERSTELLUNG VON GESCHWEISSTEN RÖHREN UND DADURCH HERGESTELLTES ROHR
Title (fr)
PROCEDE DE FABRICATION DE TUBES SOUDES ET TUBE AINSI OBTENU
Publication
Application
Priority
- FR 0203116 W 20020912
- FR 0112160 A 20010920
Abstract (en)
[origin: FR2829775A1] Fabrication of rolled and welded tube comprises: casting steel, either as an ingot that is roughed down to a slab or directly as a slab; hot rolling slab into strip and coiling; pickling the strip if it is surface oxidized; making welded tube by forming a metal sheet from the strip, bringing its edges together and butt welding; eliminating weld bead; and cold drawing or hydroforming welded tube. The fabrication of a rolled and welded tube, including a final drawing or hydroforming stage, comprises: (a) the production of a steel with a specific composition; (b) casting it as a semi-product, either as an ingot that is then roughed down to a slab or directly as a slab; (c) hot rolling the slab into strip and coiling; (d) pickling the strip if it is surface oxidized; (e) making a welded tube by forming a metal sheet cut from the strip, bringing its edges together and butt welding; (f) eliminating the weld bead; (g) finally cold drawing or hydroforming the welded tube to produce the finished product. The composition of the steel alloy is, by wt.: (a) carbon (C) <= 2%; (b) manganese (Mn) between 10 and 40%, with Mn% less than 21.66-9.7 C%; (c) silicon (Si) <= 5%, preferably <= 1%, optimally <= 0.5%; (d) sulfur (S) <= 0.3%, preferably <= 0.05%, optimally <= 0.01%; (e) phosphorus (P) <= 0.1%, preferably <= 0.05%; (f) aluminum (Al) <= 5%, preferably <= 0.1%, optimally <= 0.03%; (g) nickel (Ni) <= 5%, preferably <= 2%; (h) molybdenum (Mo) <= 5%, preferably <= 1%; (i) cobalt (Co) <= 3%, preferably <= 1%; (j) tungsten (W) <= 2%, preferably <= 0.5%; (k) chromium (Cr) <= 5%, preferably <= 1%; (l) niobium (Nb) <= 1%, preferably <= 0.1%; (m) vanadium (V) <= 1%, preferably <= 0.1%; (n) copper (Cu) <= 5%, preferably <= 1%; (o) nitrogen (N) <= 0.2%, preferably <= 0.1%, optimally <= 0.05%; (p) tin (Sn) <= 0.5%, preferably <= 0.1%; (q) titanium (Ti) <= 1%, preferably <= 0.1%; (r) boron (B) <= 0.1%, preferably 0.01%; (s) each of calcium (Ca) and magnesium (Mg) contents <= 0.1%, preferably <= 0.01%; (t) each of the arsenic (As) and antimony (Sb) contents <= 0.1%, preferably <= 0.05%. An Independent claim is also included for a welded tube fabricated by this method.
IPC 1-7
IPC 8 full level
B21C 37/08 (2006.01); C21D 8/10 (2006.01); C22C 38/04 (2006.01); C21D 6/00 (2006.01); C21D 8/02 (2006.01)
CPC (source: EP)
B21C 37/08 (2013.01); C21D 8/105 (2013.01); C22C 38/04 (2013.01); C21D 6/005 (2013.01); C21D 8/0226 (2013.01); C21D 8/0273 (2013.01)
Designated contracting state (EPC)
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR
DOCDB simple family (publication)
FR 2829775 A1 20030321; FR 2829775 B1 20031226; AT E310835 T1 20051215; DE 60207591 D1 20051229; DE 60207591 T2 20060706; EP 1427866 A1 20040616; EP 1427866 B1 20051123; ES 2254752 T3 20060616; WO 03025240 A1 20030327
DOCDB simple family (application)
FR 0112160 A 20010920; AT 02777430 T 20020912; DE 60207591 T 20020912; EP 02777430 A 20020912; ES 02777430 T 20020912; FR 0203116 W 20020912