(19)

(11)

EP 2 142 754 A2

(12)

(88) Date of publication A3: 05.02.2009 (43) Date of publication: 13.01.2010 Bulletin 2010/02 (21) Application number: 08747145.4 (22) Date of filing: 30.04.2008

(51) International Patent Classification (IPC):  E21B 34/10(2006.01) (86) International application number: PCT/US2008/061966 (87) International publication number: WO 2008/134700 (06.11.2008 Gazette 2008/45)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR (30) Priority: 30.04.2007 US 742318 30.04.2007 US 742343 (71) Applicant: Petroquip Energy Services, LLP Houston, Texas 77095 (US)	(72) Inventors: WINTILL, Charles, David Houston, Texas 77095 (US) LONG, Rodney, Wayne Houston, Texas 77095 (US) DARNELL, William, John Houston, Texas 77095 (US) DARBY, Michael, Chad Houston, Texas 77095 (US) DARNELL, William Ryle Houston, Texas 77095 (US) (74) Representative: Williams, Michael Ian  Cleveland 40-43 Chancery Lane London WC2A 1JQ London WC2A 1JQ (GB)