Nipple (Plumbing)

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Nipple (Plumbing)

What is Nipple (Plumbing)?

A short section of pipe with male threads on both ends used to connect two female-threaded fittings, valves, or fixtures in plumbing systems.

Description

A nipple (plumbing) is a short section of pipe with male threads on both ends used to connect two female-threaded fittings, valves, or fixtures in plumbing systems, available in various lengths and materials to accommodate different spacing requirements and system pressures. These essential plumbing components serve as connecting links between fittings, allowing for precise spacing and alignment in piping systems while maintaining pressure integrity and leak-proof connections. Plumbing nipples are fundamental components in both residential and commercial plumbing installations, providing flexibility in system design and maintenance.

The primary purposes include connecting two female-threaded fittings, valves, or fixtures with precise spacing, providing short-distance pipe connections in tight spaces where full pipe lengths are impractical, enabling system modifications and repairs without extensive pipe replacement, supporting proper alignment and positioning of plumbing components, facilitating maintenance access and component replacement in plumbing systems, creating reliable pressure-tight connections in water, gas, and other fluid systems, and allowing for standardized connections between different manufacturers’ components.

Types and classifications involve standard nipples, close nipples, reducing nipples, and specialty nipples for different plumbing applications.

FAQs

  • What is a plumbing nipple?

    A plumbing nipple is a short section of pipe with male threads on both ends, used to connect two female-threaded fittings, valves, or fixtures.

  • What are the common lengths for plumbing nipples?

    Common nipple lengths range from close nipples (very short) to 12 inches, with standard lengths including 1", 2", 3", 4", 6", 8", 10", and 12".

  • What materials are plumbing nipples made from?

    Common materials include galvanized steel, black iron, brass, stainless steel, and various plastics like PVC and CPVC.

  • What is a close nipple?

    A close nipple is a very short nipple where the threads nearly meet, providing minimal spacing between connected fittings.

  • How do you seal threaded nipple connections?

    Nipple connections are typically sealed using pipe thread sealant (pipe dope) or PTFE tape applied to the male threads before assembly.

  • Can nipples be used in gas systems?

    Yes, appropriate nipples (typically black iron or brass) can be used in gas systems, but must meet gas code requirements and pressure ratings.

  • How do you measure nipple length?

    Nipple length is typically measured as the overall length including threads, though some specifications may refer to the threaded length only.

Fun Fact

Fun Fact: The term “nipple” in plumbing comes from the resemblance to a baby bottle nipple – both are short connectors that join two larger components! Plumbing nipples have been used since the early days of threaded pipe systems in the 1800s. The “close nipple” gets its name because the threads are so close together they almost touch. Interestingly, some very short nipples are called “running nipples” because installers often have to “run” to the supply house multiple times to get the right length!

CSI Code

22 05 00

NAHB Code

2200