(19)

(11)

EP 1 257 730 A1

(12)

(43) Date of publication: 20.11.2002 Bulletin 2002/47 (21) Application number: 00959416.9 (22) Date of filing: 25.08.2000

(51) International Patent Classification (IPC)7: E21B 49/08, E21B 49/10 (86) International application number: PCT/US0023/382 (87) International publication number: WO 0106/3093 (30.08.2001 Gazette 2001/35)

(84) Designated Contracting States: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 25.02.2000 WO PCT/US00/04992 (71) Applicant: BAKER HUGHES INCORPORATED HoustonTexas 77027 (US)	(72) Inventor: REINHARDT, Paul, Andrew Houston, TX 77024 (US) (74) Representative: Jeffrey, Philip Michael  Frank B. Dehn & Co.179 Queen Victoria Street London EC4V 4EL London EC4V 4EL (GB)