(19)

(11)

EP 1 819 896 A1

(12)

(43) Date of publication: 22.08.2007 Bulletin 2007/34 (21) Application number: 05813505.4 (22) Date of filing: 30.11.2005

(51) International Patent Classification (IPC):  E21B 19/20(2006.01) (86) International application number: PCT/GB2005/050221 (87) International publication number: WO 2006/059153 (08.06.2006 Gazette 2006/23)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR (30) Priority: 30.11.2004 US 999815 30.11.2004 US 631954 P (71) Applicant: Varco I/P, Inc. Houston TX 77042-4200 (US)	(72) Inventors: SPRINGETT, Frank, Benjamin Houston, TX 77070 (US) ENSLEY, Eric T. Cypress, Texas 77433 (US) (74) Representative: Lucas, Phillip Brian et al Lucas & Co. 135 Westhall Road Warlingham, Surrey CR6 9HJ Warlingham, Surrey CR6 9HJ (GB)