(19)

(11)

EP 1 751 390 A2

(12)

(88) Date of publication A3: 19.10.2006 (43) Date of publication: 14.02.2007 Bulletin 2007/07 (21) Application number: 05743228.8 (22) Date of filing: 28.04.2005

(51) International Patent Classification (IPC):  E21B 7/04(2006.01) (86) International application number: PCT/US2005/014594 (87) International publication number: WO 2005/110020 (24.11.2005 Gazette 2005/47)

(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 MC NL PL PT RO SE SI SK TR Designated Extension States: AL BA HR LV MK YU (30) Priority: 30.04.2004 US 567145 P (71) Applicant: ASTEC INDUSTRIES, INC. Chattanooga, TN 37407 (US)	(72) Inventor: RIEL, William, G. Wooster, OH 44691 (US) (74) Representative: Johnstone, Douglas Ian et al Baron & Warren, 19 South End, Kensington London W8 5BU London W8 5BU (GB)