The Ultimate FAQ Guide to Pipe Nipples – Everything You Need to Know

This guide answers all questions about pipe nipples. If you have been looking for information about steel pipe nipples, look no further.

Here are the most direct yet detailed answers to the questions about carbon steel pipe fittings and stainless steel pipe nipples.

Without further ado, here we go:

1. What Is A Pipe 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, connecting two other fittings.

Nipple length is the overall length of the 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 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.

A pipe nipple is a short pipe with male threads on each end and connects two female-threaded fittings. They come in various designs:

• Hex Nipple

Hex nipples are plumbing fittings with a hexagonal section in the middle.

They are easy to install and remove with a wrench and suitable for narrow spaces. The hex nipple provides more torque and grip than the normal pipe nipple.

• Barrel Nipple

A plain cylindrical pipe section.

The barrel nipple is a pipe fitting with a cylindrical appearance and no hexagonal section. It has male threads on both ends to connect with the female-threaded pipe.

• Close Nipple

The unthreaded part of the closed nipple is too short, nearly covered by the thread, and minimally exposed when installed. Applications need a compact connection at the close nipple.

When the ends are different sizes, they are called Reducer Nipples. Threads can include DIN, BSPT, NPT, ANSI, and ASME.

2. Pipe Nipple Materials

Carbon Steel Pipe: Available in seamless or welded pipes, their strength, durability, and versatility make them popular materials in pipe nipple manufacturing.

Stainless Steel Pipe: Typically 304/304L or 316/316L, in seamless or welding pipes.

3. Pipe Nipple Finishes

Black: Made of carbon steel, coated or sandblasted, black pipe fittings use special techniques to finish the process and enhance their durability and appearance. The black finish provides anti-corrosion properties and protection during transportation. A black finish is more cost-effective than galvanized and stainless steel.

Galvanized: Electroplated or hot-dipped zinc finish for corrosion resistance to prevent steel pipe corrosion. Galvanized steel pipe enhances the pipe corrosion resistance, extends use life, and enhances its durability in various applications.

4. Pipe Nipple Types

Carbon steel pipe nipple

Stainless steel pipe nipple

Seamless pipe nipple

Welded pipe nipple

Black pipe nipple

Galvanized pipe nipple

TBE pipe nipple/Barrel nipple

TOE pipe nipple/Welding nipple

Close pipe nipple/Running nipple

Shoulder nipple

Hex nipple

Reducer nipple

Hose Nipple, etc.

5. Pipe Nipple Dimension Standard

• ASTM A733 Standard Threaded Steel Pipe Nipple

（1）Carbon Steel Pipe Nipple (black steel pipe nipple and galvanized steel pipe nipple)

Material: ASTM A53/ASTM A106 steel pipe standard specifications for steel pipe;
welded and seamless; black and hot-dipped
Thread: ANSI/ASME B 1.20.1

（2）Stainless Steel Pipe Nipple

Material: ASTM A312, 304/304L or 316/316L; welded or seamless
Thread: ANSI/ASME B 1.20.1

For example, if the pipe size is 1/8″, then the close length is 3/4″

• DIN2982, BS EN10241 Standard Threaded Steel Pipe Nipple

Type: Carbon Steel / Stainless Steel; DIN2440 / BS1387; Welded and Seamless

(1) DIN2982 Standard Threaded Steel Pipe Nipple

Material: Close Nipple/Running Nipple, DIN2441 seamless or welded pipe; Barrel Nipple, DIN2440 seamless or welded pipe
Thread: Close Nipple/Running Nipple, DIN259; Barrel Nipple, DIN2999
Finish: black, galvanized, and hot-dipped

(2) BS EN10241 Standard Threaded Steel Pipe Nipple

Material: BS1387 seamless or welded pipe
Thread: ISO 7/1 or BS 21
Finish: black, galvanized, and hot-dipped

Hebei Sanvo is one of the quality pipe nipple suppliers and manufacturers, exporting carbon steel pipe nipples, stainless steel pipe nipples, seamless pipe nipples, welded pipe nipples, galvanized pipe nipples, and black pipe nipples. If you are interested in steel pipe nipples, please do not hesitate to click here to contact us in various ways.