Patent ID: 6047771
Filing Date: 2000-04-11
Classification: E21B

Abstract:
A method for hauling up and lowering, respectively, a pipe in a bore hole in connection with drilling operations carried out by a drilling rig having a first, upper carriage with a drilling machine coupled thereto, the drilling machine being displaceably disposed along a derrick of the drilling rig, which is equipped with a driven transmission mechanism for rectilinear, reciprocating displacement movements, the method comprising the steps of:coupling a second, lower carriage to the driven transmission mechanism and guiding said lower carriage along the derrick, the lower carriage including catching means;coupling said upper carriage to the derrick, while the lower carriage is oriented by the derrick for alignment in relation to an upper end of the pipe;grabbing the upper end of the pipe with the catching means of the lower carriage;activating the driven transmission mechanism in order to effect displacement of said second carriage holding the pipe with the catching means until the pipe has been hauled up the bore hole or lowered down the bore hole, respectively;uncoupling the drilling machine from the derrick and coupling the drilling machine to the lower carriage; andjointly displacing the drilling machine and the catching means down and up with the driven transmission mechanism during the drilling operations wherein, the driven transmission mechanism being operative as a drive device for reciprocating movements at the drilling, hauling-up, and lowering operations carried out from the rig.