Patent ID: 6471439
Filing Date: 2002-10-29
Classification: E21B,Y10T

Abstract:
A slip assembly for handling a drill pipe on a drilling rig having a rotary table, comprising:a slip bowl supported in the rotary table having an upper end and a lower end and a tapered axial bore therethrough for passage of the drill pipe, said tapered axial bore having a constant slope from the upper end to the lower end; and a plurality of slip segments for insertion into the slip bowl, each slip segment comprising: (i) an upper end and a lower end; (ii) a tapered outer surface which complements the taper of the axial bore of the slip bowl and engages the axial bore of the slip bowl such that the lower end of each slip segment does not extend below the bore of the slip bowl; (iii) an inner surface which defines the shape of the axial bore for passage of the drill pipe; (iv) a circumferential groove formed in the inner bore between the upper end and lower end; (v) a load ring installed in said groove; and (vi) a plurality of axial rows of dies with gripping surfaces protruding radially inward installed in each slip segment, some of the dies in each axial row being installed below the load ring and the remainder of the dies in each axial row being installed above the load ring.