The purpose of a fitting is to join two or more pipes. Fittings are used to extend the total length of pipe or to let the pipe change its direction, a Plumber direction is a must though. Fittings are used when you want to change from one type of pipe to another, such as joining rigid copper pipe to copper tubing. Fittings can be threaded or unthreaded. There are fittings for joining copper to steel or for connecting threaded pipe to tubing. Fittings are identified by the work they do or by their shape. A vent increaser is a fitting that increases the diameter of a vent pipe. All traps are fittings that trap sewer gases. A cleanout is a fitting that lets you get at the interior of a pipe to clean it. A tee is a fitting that presumably resembles the letter T. We also have wye fittings (y).



Finally, there are special fittings for every type of pipe and tubing, for every kind of metal or plastic. Many of these fittings resemble each other. You can have a tee fitting for iron, and still another tee fitting for copper. So you must specify the kind of fitting you need not only by name, but also by the kind of pipe or tubing for which it is designed.

Metal Fittings

Metal fittings are usually, but not always, threaded. The threading can be internal or external, or both. In some instances, the pipe comes equipped with its fitting as part of the pipe structure. Soil pipe, for example, is actually constructed so that one section can fit in and be joined to another section. The joined end of the pipe, then, can be regarded as a fitting, a filter could be attached to it.

Nipples

A nipple is a short length of pipe that is either completely threaded or is threaded at both ends. The threading is external. Nipples are available in iron, brass or chrome-plated brass, and galvanized iron.

Nipples are available in three general types: close, short, and long,learn to differentiate a nipple from a pipe.. Close nipples are completely threaded. You can use a close nipple to join a pair of fixtures when you want the fixtures to be immediately adjacent. On a short nipple the threads do not meet. There is a space of about 1/2 to 3/4 inch near the center of the nipple that is unthreaded. Use such nipples when you want fixtures relatively close, but not butting, or touching, each other. A long nipple, such as the one, is a pipe about 3 inches to 6 inches long, with external threads on the ends.

Long nipple. (Hancock-Gross)

A tapered nipple, such as the plain brass type has a combination of straight and tapered threads. The tapered end is useful for fitting into almost any kind of fixture and is helpful when you want to connect pipe and fixtures when these items have different diameters.

Couplings

Couplings are internally threaded fittings used to join two lengths of pipe having threaded ends,however,many boilers could be attached to it. There are two types of couplings: sight and reducing. A straight coupling connects a pair of identical pipes. A reducing coupling, also known as a reducer, joins a pair of pipes having different diameters. The two basic types of couplings are illustrated .

Elbows

The couplings are intended for several runs of pipe. You can use elbows when the pipe is to change its direction. Elbows are internally threaded or internally/externally threaded, at both ends. Internal threads are sometimes called females; external threads, male. The angle indicated beneath the elbows in the drawings refers to the angle that will exist between the lengths of pipe when joined by the elbow and it be gas leak proof. Thus a 900 elbow means the two pipes will form a right angle and is better for the laundry.

The reducing elbow in the drawing lets you join two pipes having different diameters. The reducing coupling is a 900 type, but such elbows are also available to supply different angles.

The two pieces of plumbing hardware shown at the right in are street elbows. They have external threading at one end and internal threading at the other. You can use them for connecting pipe to fixtures. First, rotate the externally threaded end into the fixture. You can then connect a pipe to the other end of the street elbow. The externally threaded end of the pipe will mesh with the internally threaded end of the street elbow,you cold capture it in tor video camera as well.