Pipe nipples, which consist of a short straight length of pipe with a male pipe thread on both ends for joining two different female threaded fittings or pipes, are the most commonly used types of pipe fittings in the piping and plumbing industries. Pipe nipples are commonly used to connect various types of connections. Pipe nipples are most commonly seen in low-pressure pipe networks. They are designed to accommodate straight-end hoses or pipes. The working pressure of pipe nipples varies with the size and design of the pipe, as well as the temperature and fluid being transferred.
Pipe nipples are available in the industry’s broadest range of wall thicknesses and materials. Pipe nipples are created by cutting a length of pipe and connecting the ends. ASME B16.11 specifies the dimensions and materials of the pipe nipple. Seamless, threaded, grooved, barbed, bent, or welded pipe nipples are all options.
What is a Pipe Nipple?
A nipple is a fitting that is a short piece of pipe in plumbing and piping. A male pipe thread (MPT) connection is typically provided at each end of a nipple, which is used to create a watertight seal when connecting piping to threaded fittings, valves, or equipment. Pipe nipples are available in lengths up to 12″, with lengths greater than 12″ referred to as ready-cut pipe. The thread specifications are identical, but the length tolerance on a ready-cut pipe is less stringent.
Pipe nipple applications:
Pipe nipples are pipe fittings that are used in a variety of industrial applications, including:
- The industry of waste incineration
- The oil and gas industry
- The chemical processing industry
- The petrochemical industry
- Pharmaceutical industry
- Industry of food and beverages
- Paper and pulp manufacturing
- Shipbuilding industry
- Industry of machine construction
- Construction industry
- Semiconductor manufacturing
Types of pipe nipples:
Barrel Pipe Nipple
Pipe nipples, also known as barrel nipples, are tapered NPT threaded at each end with an unthreaded section in the middle unless otherwise specified. Threaded both ends nipples are commonly referred to as T.B.E, which stands for threaded both ends. When looking at the lengths of the nipple, the overall length including the threads is specified.
T.O.E. Pipe Nipple
T.O.E. nipple is an abbreviation for threaded one end. This type of nipple is commonly used as oil tank legs. T.O.E nipples are frequently confused with weld nipples, but true weld nipples have a beveled end finish that is required for butt weld connections.
Welded Pipe Nipple
Weld nipples do not have threads and are joined to tube fittings by welding rather than threading. Weld nipples are suitable for use in extreme conditions such as vibration, pressure surges, and temperature changes. Weld nipples are not weakened by cut threads, which can reduce wall thickness and thus structural strength.
Close Pipe Nipple
The close nipple has no unthreaded area, which means that when two female fittings are tightly screwed onto both ends of the nipple, only a small portion of the nipple is
exposed.Close nipples are ordered by the diameter by the close, for example, 1/2″ x close.
Shoulder Pipe Nipple
Shoulder nipples are longer than close nipples and have a very short unthreaded space between the threads. The unthreaded space is insufficient to accommodate a pipe wrench. When two female fittings are screwed onto either end, a small piece of the nipple remains exposed. A shoulder nipple is the first length of nipple available after a close nipple.
Hex Pipe Nipple
The hexagon-shaped middle section gives rise to the name “hex nipple.” The hexagon shape allows a wrench to securely grasp it. A hex nipple with two different sizes on each end is referred to as a reducer or unequal nipple.
Pipe Nipple (Right-Left Hand)
Right-left hand nipples have one end with a right-hand thread and the other end with a left-hand thread. This type of pipe nipple is commonly used in gas piping or piping applications where unions are not permitted. In installations where a union is not possible, right-left hand nipples can be used to connect to female pipe thread.
Swage Pipe Nipple
Swage nipples are used to transfer fluid flow from one pipe size to another. Swage nipples are available with plain, beveled, or threaded ends. The purpose of a swage nipple is to change the diameter of a pipe and connect two pipes of different sizes. Concentric swage nipple and eccentric swage nipple are the two types of swage nipple. Concentric swage nipple is used primarily in vertical pipelines, while eccentric swage nipple is used primarily in horizontal pipelines. Eccentric reducers can be installed in either top-flat or bottom-flat orientations; for example, flat-top installation can be used on the suction side of pumps to prevent air buildup in the pipe.
The gradual accumulation of air in a concentric reducer could produce a large bubble, causing the pump to stall or cavitation when drawn into the pump. Horizontal gas reducers are always eccentric, with the bottom flat, allowing condensed water or oil to drain at low points.
Seamless Pipe Nipple
Seamless pipe nipples lack a welded seam that runs the length of the pipe nipple. Seamless pipe nipples are stronger structurally and are intended for high-pressure applications.
Grooved Pipe Nipples
Pipe nipples with grooves are commonly used in commercial or industrial construction, mining, and process piping applications. Groove x Groove, Groove x Bevel, and Groove x MPT are the three most common configurations. They come in a variety of sizes ranging from 1-1/2″ to 12″ and are fully interchangeable with popular groove pipe-fitting brands such as Shurjoint and Victaulic.
Combination/King Pipe NippleBLCN-250
Combination nipples, also known as king nipples, are an extremely versatile method of transitioning from hose pipe to threads. End connections are only for fluid service and should not be used for air or steam service. MPT is the most common connection, but they are also available with female NPT (National Pipe Thread), flanged, or a blank beveled end for welding. Male adapters are sometimes confused with combination nipples because they look so similar, but male adapters are designed for polyethylene pipes.