Nipples

A pipe nipple is a short length of pipe, typically less than 12 inches, that has a male pipe thread on one or both ends. It's used as a fitting to connect two other fittings or to extend a piping run. Pipe nipples are vital components in plumbing, HVAC, and various industrial applications where they create secure, leak-proof connections.

Key Features & Uses of Pipe Nipples

Threads: The male threads on a pipe nipple screw into the female threads of other pipes or fittings. This connection creates a tight seal, which can be further secured with pipe sealant or Teflon tape.

Lengths and Diameters: They come in a wide range of lengths and diameters to suit various needs. The length of a nipple is measured from end to end, including the threaded parts.

Materials: Pipe nipples are made from various materials, including galvanized steel, stainless steel, brass, and PVC, each chosen for its specific properties like corrosion resistance, strength, and cost.

⦁    Galvanized Steel: For general-purpose water, gas, and air lines.
⦁    Black Steel: For gas lines, fire sprinkler systems, and steam.
⦁    Stainless Steel (304, 316): For corrosive environments, food and beverage, and high-purity applications.
⦁    Brass: For water systems and decorative plumbing where corrosion resistance and a clean look are important.
⦁    PVC/CPVC: For low-pressure systems, irrigation, and specific chemical applications where metal is not suitable.

Types of Pipe Nipples

Different types of pipe nipples are designed for specific applications:

  • Close Nipple: This type is fully threaded with no unthreaded section in the middle. When two female fittings are screwed on, they sit almost touching each other, leaving very little of the nipple exposed.
  • Shoulder Nipple: Shoulder: Similar to a close nipple, but with a very small unthreaded section.
    Barrel Nipple: The most common type, with a short unthreaded section in the middle.
  • Hex Nipple: It has a hexagonal section in the center that allows for a secure grip with a wrench, making it easier to tighten and loosen.
  • Swage Nipple: This nipple is used to connect pipes of different diameters. It has a different size on each end, allowing for a seamless transition between two pipes.
  • Hose Nipple: This fitting has a male threaded end on one side and a barbed end on the other, designed to connect a threaded pipe to a smooth hose.
  • Threaded One End (T.O.E.): A nipple with threads on only one end.

Schedule (Wall Thickness)

The schedule number relates to the wall thickness and dictates the pressure rating.

  • Schedule 40 (SCH 40): The most common and standard schedule for many applications.
  • Schedule 80 (SCH 80): Thicker walls for higher pressure applications. In plumbing and industrial piping, Schedule 80 and XH are two terms that mean the same thing: Extra Heavy pipe. They both refer to pipe with a thick wall, making it suitable for high-pressure and high-stress applications.

Finish / Coating of Pipe Nipples

  • Black: Uncoated steel
  • Galvanized: Coated with a layer of zinc for corrosion resistance