A threaded pipe plug; note that the threaded portion is slightly conical and so touches the calipers at only two points.

A threaded pipe is a pipe with screw-threaded ends for assembly. Threads are generally slightly conical rather than cylindrical (like a bolt or power screw). As a result a threaded pipe joint is much like a conical plug plugging a conical hole. In addition, the threads act as a labyrinth seal. While no gasket is needed, a coating is usually applied to the threads such as teflon tape. Image File history File linksMetadata Download high-resolution version (2272x1704, 776 KB) Photo by me of a brass NPT pipe plug. ... Image File history File linksMetadata Download high-resolution version (2272x1704, 776 KB) Photo by me of a brass NPT pipe plug. ... Pipe is a hollow cylinder of material. ... A bolt may be one of the following things: For bolts and capscrews, see Bolted joint. ... A labyrinth seal is a mechanical seal that fits around a rotating shaft to prevent the leakage of oil or other fluids. ... This article is about mechanical seals. ... A coating is a covering that is applied to an object to protect it or change its appearance. ... Teflon® is polytetrafluoroethylene (PTFE), a polymer of fluorinated ethylene. ...

Especially precise threads are known as "dry fit" meaning that no sealant is required for a gas-tight seal. Such threads are needed where the sealant would contaminate or react with the media inside the piping, e.g., oxygen service.

Due to the taper (cone) of the thread, when such threads are cut by a tap or a die, increasingly more material is being cut at a time as the length of the thread is increased. Beyond a pipe sizes of a fraction of an inch, it is therefore common to use powered tools when cutting such threads.

Threaded fittings are sometimes used on plastic piping. Due to the wedging effect of the tapered thread, extreme care must be used to avoid overstressing the female component of the joint. It is not uncommon for such fittings to split days, weeks, or even years after initial installation, and therefore many municipal plumbing codes restrict the use of threaded plastic pipe fittings.

See also

• Pipe (material)
• Plumbing
• Nipple (plumbing)
• AN thread
• British standard pipe thread (BSP)
• National pipe thread (NPT)
• O-Ring Boss Seal
• RIDGID, notable manufacturer of pipe threaders
• Taps and dies

Pipe is a hollow cylinder of material. ... The plumber wrench for screwing various pipes Plumbing, from the Latin for lead (plumbum), is the skilled trade of working with pipes and tubing for potable water systems and for drainage of waste. ... Flow Calibrated 1/4 Nipple In plumbing and piping, a nipple is a fitting, consisting of a short piece of pipe, usually provided with a male pipe thread at each end, for connecting two other fittings. ... The AN thread is a particular type of fitting used to connect flexible hoses and rigid metal tubing that carry fluid. ... British standard pipe thread (BSP), a Whitworth form pipe thread, standard in Great Britain and continental Europe. ... Threaded pipe and elbow National pipe thread (NPT) is a U.S. standard for tapered threads used around the world to join pipe and fittings. ... O-Ring boss seal is a technique for joining two fluid-carrying pipes, hoses or tubing. ... RIDGID is the popular name of the Ridge Tool Company of Elyria, OH. Founded in the 1920s as a manufacturer of professional plumbing and HVAC tools, they have relatively recently branched out into more general-purpose hand tools and power tools. ... Taps and dies are metalworking tools for the creation (cutting) of screw threads in metal parts. ...

External links

• NPT Vs. NPTF Taper Pipe Threads