Different Types of Bellows, Metal Joints, and Custom Expansion Joints for Use Across the World


Different metal expansion joints have been used over the years in many industries. These various joints are used to maintain a piping system where changes in temperature, pressure, vibration, compression, cyclical movements, and extension can be assisted by the use of the expansion joints that meet their needs. Additionally, custom expansion joints can be created for the piping systems that may exist in unique environments.

What are Bellows Used for?

One of the most common metal expansion joints is a bellow. Now, what does a bellow do? Being an elastic vessel that can be compressed upon receiving pressure from the outside or from under a vacuum. However, when the pressure or vacuum is relieved, bellows return to their original shape so long as the stress has not extended its full strength. These are the metal bellows and metal bellows expansion joints that can hold a great deal of pressure from the inside or out.

Types of Bellows Designs

There are three main types of metal bellows, including formed, welded, and electroformed. Additionally, with these being the most common metal expansion joints, these can also be formed as custom expansion joints that work specifically in shape or function for the piping system where they will be placed.

Formed bellows are manufactured by reworking tubes through many different processes such as cold forming, rolling, and hydroforming. Even more than standard bellows there are convoluted bellows, exhaust bellows, sylphons, and many more. Then welded bellows are produced by welding many individual diaphragms together. This can be done with stainless steel bellows, and is one way that custom expansion joints can be created. Then, hydroformed bellows are created still created with welding, though they have lower performance needs due to thick walls and high stiffness of the bellows themselves. So, if there is more production needed of custom expansion joints or bellows, then bellows made by plating or electroforming a metal layer onto a model and then removing the model is an affordable option.

What Can Bellows be Made of?

Most commonly, bellows and metal expansion joints are made of stainless steel, hastelloy X alloy, forged steel, iron ore, and other metals. Many of these are those which are needed for strength against pressure and heat, while sometimes it is also for protection against corrosion from the water or other liquids that will be flowing through the piping system or existing around them.

In addition, there are the processes and procedures for forming metal bellows, metal expansion joints, exhaust flex joints, exhaust bellows, custom expansion joints, and many more. So many industries rely upon these joints, along with the features and functions provided for the work of the oil and gas, construction, automotive, aerospace, and other industries. With all of this, there is much to see in the ability of custom expansion joints and others to provide for the workforce around the world.


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