What is a Socket Weld? Definition, Uses, Benefits and Drawbacks.

Pipe welding can be a rigorous task if you do not have an idea or experience of what you are accomplishing, and that is why understanding socket welding is essential. If you are completely a newbie, then the question circulating in your mind could be what is a socket weld.

It refers to a kind of weld that is formed to join particular types of pipe fittings like elbows, tees, and reducers with the pipe. The socket weld completely connects the pipe to the adjourning area of the joint. The pipe fittings you attain from this way are called socket welded pipe fittings.

Related: How to become pipeline welder


What are socket weld tube fittings?

The socket weld fittings are meant to join pipes. The pipes are put into the adjourning region of the fitting, valve, or flange. Seal welds (filled type) are manipulated to connect the pipes with fittings. Moreover, the socket weld fitting is preferable in that scenario as they have high leakage resistance and incredible strength.

These key points must be taken into account when creating a pipe network. Whenever executing such fittings, you have to point out pressure rating along with OD dimensions. Apart from that, the socket weld fitting is also known as SW fitting. In this way, SW elbows, SW tees, SW coupling, and all such things come under the domain of SW fitting.


Use of SW fittings:

As these fittings are capable of handling extreme pressure levels, they are best for industrial use. Besides that,  we utilize the SW fittings such as elbows, tees, and reducers in pipelines for transportation of fuel, chemicals, and other toxic stuff. So, you can understand that these fittings are ideal for applications where leakage can be hazardous.

The quality of these fittings is remarkable as they are built as per ASTM and ASME standards that’s why they aid in a better flow of fluids and gas. These international standards also point out prerequisites for different forms like

  • Bars
  • Forged parts
  • Seamless tubes
  • Seamless pipes

Like butt weld fittings it is also subdivided on the basis of alloys including stainless steel, carbon steel, and raw steel. According to the sort of use you can pick SW elbows, SW tees, SW flanges, reducers, couplings, and other connectors on the grounds of their built material. There are the following types of socket weld fittings:

1.    Socket weld cross

This fitting helps in connecting four pipes with two pairs at a 45-degree angle. It has great significance as it enables creating a broad pipe network.

2.    Socket weld cap

From its name, it is obvious that it is used to seal the pipe by putting an end of the pipe in it.

3.    Socket weld flanges

SW flanges are used to join high-pressure pipes of very small diameters. The major benefit of this fitting is it enables a fast flow rate.

4.    Sockolet

It has the same use as weldolet and threadolet. You can use it to weld a small diameter pipe with a large diameter pipe.

5.    Socket weld tee

This fitting in between two pipes gives the option to connect the third pipe at a 90-degree angle between the two pipes. The key feature is you can attach a smaller pipe at a 90-degree angle between two pipes.

6.    Socket weld elbow

They play a crucial role in the making of pipe networks as they divert the direction of fluids. Besides that, they come in two different categories; 45-degree and 90-degree.

7.    Socket weld union

It contains three parts. Among them, two are internal threads, and one is a midpiece which brings both sides closer when you rotate it. So, you have to screw it properly before executing the welding process.

8.    Socket weld reducer

These fittings let the welder/plumber connect pipes of uneven diameters. Moreover, there are made as per ASME and ASTM standards.

9.    Full coupling

Both ends have threads. Therefore, you can use it for joining two pipes of the same diameter.

10.  Half coupling

Only one end has threads. One pipe is joined with the threaded side, whereas the other side of the coupling is connected with the pipe by welding

11. Reducing coupling

This type of coupling has one small and one large end, but both have threads. So, you can use it to connect two pipes of uneven diameter.

Benefits of socket weld pipe fittings

  • You have to bevel the pipe to prepare it for welding
  • No need to create tack welds to arrange pipes appropriately because the layout of these fittings provides perfect alignment
  • These are the best replacement for threaded fittings as there is a minimal chance of leakage
  • Most importantly, it is very adorable to install socket weld fittings than butt weld fittings

Drawbacks of socket weld pipe fittings

  • These are not ideal for the food industry as they do not permit full penetration, and the cervices they possess are challenging to clear
  • There must be a particular expansion gap between the pipe and socket shoulder
  • External gaps and inner services tend to corrode, so they are suitable for transporting corrosive and radioactive substances.