Back to results
US 7,069,817 B2Granted
Power tongs
OwnerWilliam E. Wesch, Jr.inventor
Life of this patent
Estimating the term…
Abstract
Damage to pipe resulting from non-uniform application of gripping forces is minimized by modified power tongs employing pivoting jaws which automatically adjust to the circumference of the pipe. The pivoting jaws pivot about mounting pins which pass through an elongated aperture in the jaw. The aperture is elongated in a direction which allows the arcuate pipe-gripping surface on the jaw to align itself concentric with the outer surface of the pipe so that the gripping force applied by the jaw is uniformly distributed over the arcuate pipe-gripping surface of the jaw.
Claims35
A power tong comprising:
- a frame;
- an outer ring rotatably supported on the frame and having a side opening through which pipe may pass to a central position in the tong;
- a releasable pipe-gripping mechanism comprising:
- (i) an inner ring;
- (ii) an active jaw mounted on said inner ring moveable radially with respect to said inner ring between an open position and a closed position and which has an arcuate-shaped pipe-gripping surface on the first end thereof and first and second camming surfaces on the opposite end thereof, said camming surfaces extending from opposite edges of said opposite end to an apex at the centerline extending from said first end of said active jaw to said opposite end thereof;
- and (iii) at least one side jaw mounted on said inner ring and pivotal between a closed position and an open position;
- means for rotating said outer ring with respect to said frame and said inner ring;
- rollers mounted on said outer ring rotatably supporting said inner ring coaxially on the outer ring with at least one of the rollers positioned to engage said first camming surface and move said active jaw toward a closed position when said outer ring is rotated in a first direction, at least one roller positioned to engage said second camming surface when said outer ring is rotated in the opposite direction, and at least one roller positioned to engage said side jaw and pivot said side jaw toward a closed position when said outer ring is rotated with respect to said inner ring;
- and
- means for limiting relative rotational movement of said inner ring with respect to said outer ring,
- wherein said means for limiting relative rotational movement of said inner ring with respect to said outer ring comprises:
- a member secured to and rotatable with said outer ring having an elongated arcuate aperture therein, the length of said arcuate aperture defining the limits of desired rotational movement of said outer ring with respect to said inner ring;
- and a limit pin secured to said inner ring and projecting into said elongated arcuate aperture.
10 more elements
A power tong comprising:
- a frame;
- an outer ring rotatably supported on the frame and having a side opening through which pipe may pass to a central position in the tong;
- a releasable pipe-gripping mechanism comprising:
- (i) an inner ring;
- (ii) an active jaw mounted on said inner ring moveable radially with respect to said inner ring between an open position and a closed position and which has an arcuate-shaped pipe-gripping surface on the first end thereof and first and second camming surfaces on the opposite end thereof, said camming surfaces extending from opposite edges of said opposite end to an apex at the centerline extending from said first end of said active jaw to said opposite end thereof;
- and (iii) at least one side jaw mounted on said inner ring and pivotal between a closed position and an open position, said side jaw including an elongated pipe-gripping element having a pivot end and a free end with an arcuate pipe-gripping surface on one side edge thereof and camming surfaces on the side edge thereof opposite the arcuate pipe-gripping surface;
- and said side jaw further including an elongated aperture journaled about a mounting pin on said inner ring to permit said arcuate pipe-gripping surface to pivot between an open position and a closed position where said arcuate pipe-gripping surface engages a pipe in said central position in the tong and to permit said pivot end to move with respect to said mounting pin within the limits of said elongated aperture so that the arc of the arcuate pipe-gripping surface is adjusted to be substantially concentric with the outer surface of the pipe;
- means for rotating said outer ring with respect to said frame and said inner ring;
- rollers mounted on said outer ring rotatably supporting said inner ring coaxially on the outer ring with at least one of the rollers positioned to engage said first camming surface and move said active jaw toward a closed position when said outer ring is rotated in a first direction, at least one roller positioned to engage said second camming surface when said outer ring is rotated in the opposite direction, and at least one roller positioned to engage said side jaw and pivot said side jaw toward a closed position when said outer ring is rotated with respect to said inner ring;
- and
- means for limiting relative rotational movement of said inner ring with respect to said outer ring.
8 more elements
In a power tong comprising a frame with a side opening to permit entry of pipe to a central position in the tong, an outer ring having a side opening and mounted for rotation on said frame, and an inner ring having a side opening and mounted for rotation on said outer ring, a pivotal jaw comprising:
- an elongated body having first and second ends and first and second side edges extending from and connecting said first and second ends;
- an arcuate pipe-gripping surface on said first side edge of said elongated body and disposed toward said second end, said arcuate pipe-gripping surface adapted to engage and grip the outer surface of pipe disposed in the central position of the tong;
- an elongated aperture in the first end of said pipe-gripping element, said elongated aperture being journaled on a mounting pin carried on said inner ring;
- first and second camming surfaces on the second side edge of said elongated body;
- rollers mounted on said outer ring and positioned to engage said camming surfaces when said outer ring is rotated with respect to said inner ring;
- and
- a third camming surface on the second side edge of said elongated body, said third camming surface defining an arc intermediate said first camming surface and said second camming surface which is substantially concentric with said arcuate pipe-gripping surface on the first side edge of said elongated body.
4 more elements
A power tong, comprising:
- a frame;
- multiple jaws rotatably supported relative to the frame, the jaws being operative to securely grip a pipe received in the frame when the jaws are rotated in a first direction relative to the frame and when the jaws are rotated in a second direction opposite to the first direction relative to the frame, without detaching the jaws from the frame between the rotations in the first and second directions;
- an outer ring rotatably supported relative to the frame;
- first and second apertures;
- and
- a member, the member limiting a gripping force applied by the jaw to the pipe when the outer ring is rotated in the first direction relative to the frame with the member received in the first aperture, and the member limiting the gripping force applied by the jaw to the pipe when the outer ring is rotated in the second direction relative to the frame with the member received in the second aperture.
3 more elements
A power tong, comprising:
- a frame;
- first, second and third jaws rotatably supported relative to the frame, the second and third jaws pivoting relative to the frame to engage a pipe received in the frame prior to the third jaw displacing relative to the frame to engage the pipe, and the first, second and third jaws being approximately equally spaced apart when all of the first, second and third jaws engage the pipe;
- an outer ring rotatably supported relative to the frame;
- first and second apertures;
- and
- a member, the member limiting a gripping force applied by the third jaw to the pipe when the outer ring is rotated in the first direction relative to the frame with the member received in the first aperture, and the member limiting the gripping force applied by the third jaw to the pipe when the outer ring is rotated in the second direction relative to the frame with the member received in the second aperture.
3 more elements
A power tong, comprising:
- a frame;
- an outer ring rotatably supported relative to the frame;
- at least one jaw for gripping a pipe received in the frame;
- first and second apertures;
- and
- a member, the member limiting a gripping force applied by the jaw to the pipe when the outer ring is rotated in a first direction relative to the frame with the member received in the first aperture, and the member limiting the gripping force applied by the jaw to the pipe when the outer ring is rotated in a second direction opposite to the first direction relative to the frame with the member received in the second aperture.
3 more elements
A power tong, comprising:
- a frame configured for receiving a pipe therein;
- first, second and third jaws rotatably supported relative to the frame, the first, second and third jaws being operative to grip the pipe at locations approximately equally spaced apart about the pipe;
- an outer ring rotatably supported relative to the frame;
- first and second apertures;
- and
- a member, the member limiting a gripping force applied by the third jaw to the pipe when the outer ring is rotated in the first direction relative to the frame with the member received in the first aperture, and the member limiting the gripping force applied by the third jaw to the pipe when the outer ring is rotated in the second direction relative to the frame with the member received in the second aperture.
3 more elements
A power tong, comprising:
- a frame;
- at least one jaw rotatably supported relative to the frame for gripping a pipe received in the frame, and the jaw further being pivotable about a pivot pin received in an elongated aperture;
- an outer ring rotatably supported relative to the frame;
- first and second apertures;
- and
- a member, the member limiting a gripping force applied by the jaw to the pipe when the outer ring is rotated in a first direction relative to the frame with the member received in the first aperture, and the member limiting the gripping force applied by the jaw to the pipe when the outer ring is rotated in a second direction opposite to the first direction relative to the frame with the member received in the second aperture.
3 more elements
Dependencies are inferred from the claim text.