DEVICE FOR STEERING THE FOREMOST PART OF A DRILL PIPE

摘要

2067802 9108370 PCTABS00005 Apparatus for directing and steering the foremost part of a drillstring at earth drillings, which apparatus is provided with a piston (43) contained in a housing, and which piston under steering of the mass flow of the drilling fluid is displaceable between two or more end positions, and wherein the piston is coupled to at least one set member, which cooperates with means for steering the end of the drillstring.