- Pipe fittings and couplings are used in most piping projects.plumbing image by Inger Anne Hulb?|kdal from Fotolia.com
There are many different types of pipe couplings on the market, but they can be classified into a much smaller group of similar objects. Keep in mind that not all couplings are available for all types of pipe, or in every diameter or fitting size. There are also specialty couplings that perform a specific function, such as as plugs, nipples and flanges. A coupling is technically any pipe fitting, but there is a particular fitting called a coupling as well, and it is important not to confuse the two terms.
- A coupling is used to connect two sections of pipe together. Couplings are usually double-ended, straight sleeves that attach to pipe at each end, and may be attached by screwing the pipe into the coupling, brazing or through the use of blue or other bonding agents.
- This type of coupling is used to connect pieces of pipe which may be of slightly different sizes, that meet at an uncommon angle or where one or both pipes is subject to minor movements that could dislodge a rigid coupling. These are commonly used in plumbing repairs where it is labor intensive to move pipes into position or there is little available material to work with.
Tees and elbows
- An elbow is a pipe fitting that makes a single turn, usually at either a 45 or a 90 degree angle. A tee combines the straight coupling with a second outlet, which is usually placed perpendicular to the straight coupling, forming a characteristic "T" shape although some resemble a "y" as well. Tees and elbows are available for all types and sizes of pipes and tubes.
- An adapter is used to change the diameter between two differing pipes. Adapters are available in four primary types: male, female, male-to-female and female-to-male, designated by which diameter is larger or smaller and how the pipe ends are connected. Adapters are the most versatile of pipe fittings because they allow the piping to branch into larger or smaller bores and connect pipes of differing connection demands.
Side Outlet Couplings
- Side outlet fittings are tees or elbows with another outlet added at a 90 degree angle to the original outlets. These fittings are rarely used, but are useful in branching service at an existing location. In PVC pipe constructions, side outlet couplings are used more frequently as the corner couplings for chairs and tables.