Abstract: An improved die insert for gripping oil field tubular members in tubular handling systems such as power tongs, slips, safety clamps and the like. The die insert has a gripping surface which comprises a backing surface adapted to contact the tubular member. The backing surface may be smooth or it may have a series of teeth formed thereon. The backing surface further has a granulated particle coating applied thereto which forms the gripping surface of the present invention. In a preferred embodiment, the gripping surface will include a refractory metal carbide selected from the group consisting of the carbides of silicon, tungsten, molybdenum, chromium, tantalum, niobium, vanadium, titanium, zirconium, and boron.

Abstract: A power tong or back-up tong has a jaw assembly that is advanced into engagement with a pipe through a cam follower that contacts the camming surface on the inside circumference of a ring gear, the cam follower being in the form of a series of roller elements arranged as a circulating bearing. In a preferred form, the roller elements are cylindrical roller bearings and the jaw assembly is mounted for sliding advancement towards the pipe to be engaged.

Abstract: A jaw adapter for use in a pivoting jaw power tong having a cage plate designed to house a pivoting jaw member. The jaw adapter includes an adapter body shaped to fit between the cages plates of a pivoting jaw power tong. The adapter body further includes a pin assembly for engaging at least one of the cage plates, and the adapter body still further includes a sliding jaw passage. A jaw assembly is then positioned within the sliding jaw passage.

Abstract: An improved die insert for gripping oil field tubular members in tubular handling systems such as power tongs, slips, safety clamps and the like. The die insert has a gripping surface which comprises a backing surface adapted to contact the tubular member. The backing surface may be smooth or it may have a series of teeth formed thereon. The backing surface further has a granulated particle coating applied thereto which forms the gripping surface of the present invention. In a preferred embodiment, the gripping surface will include a refractory metal carbide selected from the group consisting of the carbides of silicon, tungsten, molybdenum, chromium, tantalum, niobium, vanadium, titanium, zirconium, and boron.

Abstract: A gripping arrangement for gripping casing is both sufficiently flexible to conform to said casing and substantially inelastic. In a preferred embodiment the gripping arrangement comprises a sheet of zircon paper bonded to a flexible metal carrier plate which has side flanges which fit into an arcuate recess in a jaw holder and bear against the ends of an arcuate pad of resilient elastomeric material. In use, radial forces are applied uniformly through the arcuate paid whilst circumferential forces are transmitted through the flexible metal carrier plate and the side flanges to the arcuate pad and thus to the jaw holder.

Abstract: A tong for rotating tubulars, the tong having, in certain embodiments, a tong outer case, a rotary movably mounted in the case for rotating a tubular, apparatus for rotating the rotary to rotate the tubular, at least one gripper or jaw movably mounted in the case and movable by the rotary for gripping the tubular, the at least one gripper or jaw having at least one cam following member or roller, and at least one non-circular cam surface on the rotary, the at least one cam following member or roller contacting and movable on the at least one non-circular cam surface for maintaining a desired position of the at least one gripper or jaw with respect to the tubular. In certain embodiments a specific cam angle, within certain tolerances, is maintained substantially the entire length along a cam surface.

Abstract: An open throat power tong 10 for making up and/or breaking apart an oilfield tubular connection includes an open throat in the tong body 15. Motors 18, 20 rotate a partial ring member 12 and a pair of heads 16 with respect to the tong body. A door 40, 140 may be opened to expose the open throat of the power tong, and has a planar latch surface formed from arcuate groove 58 for receiving an arcuate boss 90. The door latch mechanism reduces the effort required to safely latch the door in the closed position before operating the tong, and provides a highly reliable mechanism to minimize spreading of the tong body under a relatively high torque.

Abstract: Apparatus for gripping tubular members including self aligning gripping jaws with high coefficient of friction for resisting force applied to the elongated member to prevent rotation either clockwise or counterclockwise. Linear cams and cam rollers actuated by a fluid cylinder bring the gripping jaws to an elongated member, applying predetermined gripping force and retract the jaws for removal of the elongated member.