COUPLING, SOCKET

A Pipe Coupling or Coupler plays an important role in connecting the pipe sections while maintaining the integrity of the pipes in the process.  It is a very useful pipe fitting for the piping and plumbing industry. Most pipe installations require several lengths of pipe to be joined together or cut to facilitate changes in direction and crossing of obstacles. Pipe Coupling is a very short length of pipe or tube. It has socket or female pipe threads at one or both ends. Pipe coupling allows two pipes or tubes of equal or different sizes to be joined together to make a long pipe run.

Removable Pipe Coupling

Removable pipe couplings use threads to allow them to be screwed onto the pipes to be joined. For example, A basic pipe section slightly larger than the pipes to be joined can be cut with an internal thread to act as a removable pipe coupler. The ends of the pipes are also threaded, and the coupler is simply sealed with hemp or sealing tape and screwed onto both pipes.

Pipe Couplings Types

There are three types of coupling available

1.   Full Coupling

2.   Half Coupling

3.   Reducing Coupling

4.   Compression Coupling

5.   Slip Coupling / Repair Coupling

What is a Full Coupling

·         Full Coupling is used for connecting small bore pipes. It used to connect pipe to pipe or pipe to swage or nipple. It can be threaded or socket ends types.

·         A socket weld full coupling is used to join small-bore plain end pipes where the pipe spec requirement is socket weld. A threaded full coupling is used to join small bore pipes with threaded ends. If the two ends of coupling are different (e.g. one BSP threaded and one NPT threaded), then it is usually referred to as an adapter.

What is Half Coupling?

·         Half Coupling is used for small bore branching from a vessel or large bore pipe. It can be threaded or socket type. It has a socket or thread end on only one side.

·         A socket weld half coupling can be directly welded to a large bore pipe, to make a branch connection. It is used to take a small bore pipe branch-off from a large bore pipe where the pipe spec requirement is socket weld in small bore size. A threaded half coupling only has one thread end and another end of the coupling should be butt welding end with either a plain end or a bevel end.

·         Reducing coupling is used to connect pipes of dissimilar diameters. A reducing coupling has two different sizes of threads on each side. Reducing couplings are typically used where small process feeder lines are joined into large supply circuits or where small diameter fittings are installed.

·         Reducing couplers feature a simple, stepped down profile and screw onto the two lengths of pipe in the same way a standard pipe joint does. Welded reducing coupler designs are similar to threaded design without the threads.

Compression Coupling

·         A compression coupling connects two perfectly aligned pipes in which a slotted tapered sleeve is placed over the junction and two flanges are drawn over the sleeve so that they automatically center the pipes and provide sufficient contact pressure.

Some important features of pipe couplings are as follows:

·         Pipe Couplings come in all standard pipe sizes and are available for almost all types of pipe

·         Mostly cylindrical in design.

·         Available in several finishes.

·         Couplings compensate for axial, lateral, and angular shaft misalignment.

·         Couplings operate in a quiet and smooth way.

·         There is a great degree of torsional stiffness.

·         There is the right angular transmission of angular motion and torque.

·         Usually long life.

·         Easy mounting and dismounting.

·         Low lateral stiffness etc.

·         Available stock of ASME B16 9 Buttweld Fittings