What Are Spinning Tongs Used For?

Drilling

• Oil wells are dug by a rotary bit mounted on the end of a long pipe; as the pipe turns, the bit turns also, and its teeth chew into the rock. The pressure created by the weight of the pipe keeps the bit tearing away at the rock face. Drilling mud flows down the pipe, through the drill bit and back up the sides, removing ground-up rock and other debris from the cutting surface.

Pipe

• As the drill descends, the crew must continue to add new pipe, because the distance from rig to drill is continually growing greater. Adjacent segments of pipe are joined by threaded connections and these "joints" are made fairly tight. The spinning tongs are basically a large wrench used to unscrew these joints and separate sections of the pipe or alternatively screw adjacent sections together. They are usually pneumatically or hydraulically operated, so they can provide a lot of torque.

Nomenclature

• Spinning tongs go by a lot of different names. They may be called "casing tongs," "pipe tongs," "rotary tongs," a "spinning wrench" or merely "tongs," depending on the use. They can also be used to assemble contiguous sections of casing, a large-diameter pipe inserted into the well at predetermined intervals. Just like the pipe on the drill shaft, the casing must also be assembled with the aid of the spinning tongs.

Considerations

• In the jargon of the drilling industry, "breaking" a joint with the spinning tongs means loosening it. Once it's been broken, the spinning chain can be turned around the pipe several times, then pulled out to quickly unscrew the joint. When pipe or tubing must be assembled, the process is reversed; first, the spinning chain is used to quickly screw the two ends together, then the spinning tongs are used to make the joint tight and apply torque.