(19)

(11)

EP 2 013 439 A1

(12)

(43) Date of publication: 14.01.2009 Bulletin 2009/03 (21) Application number: 07793934.6 (22) Date of filing: 19.04.2007

(51) International Patent Classification (IPC):  E21B 10/08(2006.01) (86) International application number: PCT/NZ2007/000089 (87) International publication number: WO 2007/120059 (25.10.2007 Gazette 2007/43)

(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 MT NL PL PT RO SE SI SK TR Designated Extension States: AL BA HR MK RS (30) Priority: 19.04.2006 NZ 54668606 21.11.2006 NZ 55143706 (71) Applicant: Drill Tech Limited Paeroa, 3600 (NZ)	(72) Inventor: FORD, Glenn, Michael Paeroa, 3600 (NZ) (74) Representative: Williams, David John  Page White & Farrer Bedford House John Street London WC1N 2BF London WC1N 2BF (GB)