Spinning chain

A Y-shaped chain used to spin up (tighten) one joint of drill pipe into another. In use, one end of the chain is attached to tongs, another end is attached to the spinning cathead, and the third end is free. The free end is wrapped around the tool joint and the cathead pulls the chain off the joint, causing the joint to spin (turn) rapidly and tighten up. After the chain is pulled off the joint, the tongs are secured in the same spot, and continuous pull on the chain (and thus on the tongs) by the cathead makes the joint up to final tightness.

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2014-07-09T20:45:43+00:00