What is a threaded 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 length of the nipple is usually specified by the overall length with thread. It may have a hexagonal section in the center for a wrench to grasp (sometimes referred to as a “hex nipple”), or it may simply be made from a short piece of pipe (sometimes referred to as a “barrel nipple” or “pipe nipple”). A “close nipple” has no unthreaded area; when screwed tightly between two female fittings, very little of the nipple remains exposed. A close nipple can only be unscrewed by gripping one threaded end with a pipe wrench which will damage the threads and necessitate replacing the nipple, or by using a specialty tool known as a nipple wrench (or known as an internal pipe wrench) which grips the inside of the pipe, leaving the threads undamaged. When the ends are of two different sizes it is called a reducer or unequal nipple.Threads used on nipples are BSP, BSPT, NPT, NPSM and Metric…
Specifications of nipple
| Shape | Threaded One End (TOE) and Threaded Both End (TBE) |
| Size Range | 1/4” – 12” / DN8 – DN300 |
| Thickness Range | Sch 10 – Sch 160 / XXS |
| Standard | ASTM A733 |
| End Type | Plain (PE), Beveled (BE), Thread (THD) |
| Thread Type | NPT, PT, BSPP, BSPT, PF |
| Carbon Steel | ASTM A105 / A106B |
| Low Temp Carbon Steel | ASTM A350 LF2/LF3, 16Mn |
| Pipeline Steel | ASTM A694 F42 / 46 / 56 / 60 / 65 |
| Alloy Steel | ASTM A182 F11 / 12 / 5 / 9 / 91 / 92 |
| Stainless Steel | ASTM A182 F304/304L/304H, 316/316L, 310S, 317,347,904L |
Difference between nipple and coupling
The difference between a pipe nipple and a pipe coupling is the difference between male and female threads.A pipe nipple is a short piece of pipe with threads on the outside of both ends – two male ends.A pipe coupling is larger in diameter and had threads on the inside – female joint.Also, a coupling can be threaded along its entire length, but it’s not kosher to have an all-thread nipple. For a nipple, at least some of the pipe has to be uncircumcised.A coupling can be used to join two nipples together.
