Pipe Joints

Published: | Updated: June 18, 2021

Definition - What does Pipe Joints mean?

Pipe joints are connections at pipe ends that ensure that two pipe sections can be joined to each other to install a pipeline of any length. Joints give strength to the pipeline because longer pipeline sections tend to bend. Joints should be joined together properly to ensure that a tight seal is established to prevent leakage.

Pipe joints are integral to any piping system because it is not possible to have a continuous length of pipe for a pipe network. These joints can make or break a pipeline system depending on the resulting durability of the technique used to form the joint. There are different materials of pipes used in the pipeline industry depending on the need and the type of product that will be conveyed through the pipe.

Different methods are used to join pipes based on the pipe material. Threaded pipe joints are used to join cast iron (CI), galvanized iron (GI), polyvinyl chloride (PVC), copper pipes, etc. They are connected by screwing the threads provided externally on one side and internally on the other side in each pipe. Such joints are suitable for low temperature and low flow conditions.

Brazing and solder pipe jointing are done on copper or copper alloy pipes by using molten filler material. For the same diameter pipes, butt welding is used to join the pipes as this gives high strength to resist high pressure. Socket welded joints are used to join pipes of different diameters and where chances of leakage are high. Flanged joints are connected using two flanges secured with bolts and are used for large diameter pipes with high-pressure flows. Polyethylene (PE) pipes are joined to each other by heat fusion or with mechanical fittings.


Trenchlesspedia explains Pipe Joints

Pipe joints are a very crucial aspect of pipe installation or rehabilitation. Pipes should be inspected to ensure that pipe ends are not damaged as this can impact the joining process. Improperly jointed pipes can fail and cause damage to property and sometimes fatal accidents.

Pipe Joining Methods

Three main methods are used to join pipes namely, butt welding, socket welding, and screwed joints. Other methods include brazed and soldered joints, grooved joints, flanged joints, and compression joints. Pipes larger than 2 inches in diameter are usually buttwelded as they are very economic and create leak-proof joints. Bolted flange joints are used for joining large diameter piping with flanged vessels or equipment or where periodic cleaning is a necessity. Smaller diameter pipes can be joined using threaded joints or socket welding.

Common Fittings used for Pipe Joints

Some types of pipe fittings used to join pipes include (not limited to):

· Elbows are used for changing the pipe direction by 45 or 90 degrees. They can be short radius or long radius type.

· Reducing elbows are used to make a change in line size along with a change in direction.

· Return pipe bends are used to make 180 degrees change in direction.

· Reducers are used to change the size of a pipe such as joining a larger pipe to a smaller one. They can be concentric or eccentric.

· Flanges are fitted to pipe ends, valves, etc. and are connected by bolting.

· Tee is used to make a branch at 90 degrees from the main pipe. They can be straight tee and reducing or unequal tee.

· Wye tee or lateral tee has a branch at 45 degrees or another angle but not at 90 degrees. This allows another pipe to be joined at that angle and helps in reducing friction and turbulence.

· Cross is a four-way pipe fitting with one inlet and three outlets or vice versa.

· Pipe caps are used to cover pipe ends.

· Unions are used as flange alternatives in low-pressure small-bore piping where pipe dismantling is done often.

Share this: