(19)

(11)

EP 2 176 492 A1

(12)

(43) Date of publication: 21.04.2010 Bulletin 2010/16 (21) Application number: 08775535.1 (22) Date of filing: 04.07.2008

(51) International Patent Classification (IPC):  E21B 7/02(2006.01) E21B 44/00(2006.01) E21B 15/04(2006.01) (86) International application number: PCT/FI2008/050410 (87) International publication number: WO 2009/007502 (15.01.2009 Gazette 2009/03)

(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 Designated Extension States: AL BA MK RS (30) Priority: 06.07.2007 FI 20075523 (71) Applicant: Sandvik Mining and Construction Oy 33330 Tampere (FI)	(72) Inventor: VALKEINEN, Risto FI-35480 Längelmäki (FI) (74) Representative: Kaukonen, Juha Veikko  Kolster Oy Ab Iso Roobertinkatu 23 P.O. Box 148 00121 Helsinki 00121 Helsinki (FI)