(19)

(11)

EP 1 301 684 A1

(12)

(43) Date of publication: 16.04.2003 Bulletin 2003/16 (21) Application number: 01949778.3 (22) Date of filing: 20.07.2001

(51) International Patent Classification (IPC)7: E21B 33/12, E21B 33/1295 (86) International application number: PCT/GB0103/272 (87) International publication number: WO 0200/8569 (31.01.2002 Gazette 2002/05)

(84) Designated Contracting States: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR Designated Extension States: AL LT LV MK RO SI (30) Priority: 20.07.2000 GB 0017691 (71) Applicant: Weatherford/Lamb Inc.The United States Corporation Company Wilmington, DE 19805 (US)	(72) Inventors: MILLAR, David Martin Angos DD7 6DY (Scotland) (GB) VAN DORT, Roland Marcel Aberdeen AB14 0XP (Scotland) (GB) (74) Representative: Harding, Richard Patrick  Marks & Clerk,4220 Nash CourtOxford Business Park South Oxford OX4 2RU Oxford OX4 2RU (GB)