(19)

(11)

EP 1 423 219 A1

(12)

(43) Date of publication: 02.06.2004 Bulletin 2004/23 (21) Application number: 02765741.0 (22) Date of filing: 04.09.2002

(51) International Patent Classification (IPC)7: B21D 31/04, C21D 7/10 (86) International application number: PCT/SE2002/001577 (87) International publication number: WO 2003/020456 (13.03.2003 Gazette 2003/11)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR Designated Extension States: AL LT LV MK RO SI (30) Priority: 05.09.2001 SE 0102943 (71) Applicant: Avestapolarit AB 774 80 Avesta (SE)	(72) Inventors: CARLSSON, Leif S-465 91 Nossebro (SE) GROTH, Hans S-774 61 Avesta (SE) (74) Representative: Rosenquist, Per Olof  Bergenstrahle & Lindvall AB,P.O. Box 17704 118 93 Stockholm 118 93 Stockholm (SE)