(19)

(11)

EP 1 058 768 A1

(12)

(43) Date of publication: 13.12.2000 Bulletin 2000/50 (21) Application number: 99907993.2 (22) Date of filing: 17.02.1999

(51) International Patent Classification (IPC)7: E21B 33/03 // F24J3:08 (86) International application number: PCT/SE9900/207 (87) International publication number: WO 9943/922 (02.09.1999 Gazette 1999/35)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB IT LI NL SE (30) Priority: 27.02.1998 SE 9800628 (71) Applicant: ALEXANDERSSON, Hans S-513 00 Fristad (SE)	(72) Inventor: ALEXANDERSSON, Hans S-513 00 Fristad (SE) (74) Representative: Lindberg, Klas Valter Bo et al Awapatent ABP.O. Box 11394 404 28 Göteborg 404 28 Göteborg (SE)