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Pipe Union

Pipe Union is a type of fitting equipment designed in such a way to unite two pipes which can be detached without causing any deformation to the pipes. Any kind of small diameter piping connections requiring a positive seal and easy assembly as well as disassembly are made with the help of pipe union. In other words, the pipe unions can disjoint two pipes very easily. They are widely demanded in the pipe fitting market.

Materials used:
  • Stainless steel
  • Cast iron
  • Aluminum
  • Nickel
  • Copper
  • Brass
  • Bronze
  • Alloy
  • Plastic
  • Rubber etc.

Buyer's guide

Important features that buyers should look for:
  • Type
  • Standard
  • Material
  • Size
  • Durability
  • Easy to install
  • Corrosion resistance
Three parts of pipe union:

A pipe union consists of three parts – a nut, a female end and a male end. To make an effectively working pipe fitting, both the male and female ends are sealed together with the help of nuts. A female threaded fitting has threads on the inside, while in the male-threaded fitting, the threads are on the outside. As the pairing ends of the union can be interchanged, these pipe fittings can be easily changed in a short span of time.

  • A nut
  • A female end
  • A male end
With the joining of the female and male ends, the nuts are used to provide the necessary pressure to seal the joint.
The parts of the pipe union are normally locked together by at least one radial screw or nut with sized cross section. When severe pulling stress is applied onto the pipe union from the outside, the locking screw breaks and removes the two parts of the union, which in turn separates together with the pipes to which they are attached. Under normal conditions elastically stressed sealing objects ensure maintenance of watertightness between the union parts.

Types of pipe unions:
There are two basic types of pipe unions:
  • Ground Joint Union : A ground joint union comprises of an angle that is cut into the union to make the two sections meet. It increases the surface area at the joint allowing seating properly.
  • Flange Union: It is a pair of flanges that holds two pipes together by screwing them on the ends of the pipes after which they are welded or bolted together. This process in plumbing is done to hold both the pipes together.
The difference between the two is that the former consists of three pieces while the latter two pieces.

Applications of pipe unions:
Pipe unions are used in various municipal and industrial applications like as follows:
  • Fire protection
  • Process piping system
  • Water and wastewater etc.

Advantages of pipe union:
There are various advantages of pipe unions like:
  • To provide a leak-proof disconnection point in any piping system.
  • Used for inserting metering and regulating devices into any plumbing application.
  • Can connect piping system to vessels.
  • Can join two pipes of different size together.
  • Can easily remove the join between two pipes.
  • Easy to install.
  • Economical.
pipe union fitting