Apparatus for pulling drill pipe has four hydraulic legs which extend and retract surface engaging feet to raise and lower a frame. A drill pipe gripping mechanism is mounted to the frame and comprises a slip bowl with an inner surface tapering inwardly and downwardly and a plurality of wedge-shaped slips which have one surface tapered to engage the inner surface of the slip bowl and the other surface parallel to the axis of the slip bowl. The slips slide down to engage a drill pipe surface and the hydraulic legs are extended to pull the pipe upwards. A control ring is mounted to the frame for limited axial movement and connecting members connect each slip to the control ring. A plurality of smaller hydraulic cylinders are connected between the frame and the control ring so that when these cylinders are extended the control ring is raised to pull the slips upwardly and thus ensure the slips disengage the surface of the drill pipe before the four hydraulic legs are retracted for the next cycle.
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