Expansion joints is a device that contains one or more bellows, which is used to assist structural changes, such as those generated by the thermal expansion, tube, or vessel.

Expansion joints can be used to allow movement within the pipe system. Bellows expansion joints flexible part which usually consists of several folds.

There are three basic types of movement that can be applied to the bellows and these are: axial, movement in a direction parallel to the longitudinal axis; lateral, movement perpendicular to the longitudinal axis; and the angle, the rotational movement of the longitudinal axis.

Metal expansion joints are widely used in the pipe system. They are essential elements for these technologies. Changes pipeline length is usually the result of high-temperature differences, which the metal joints are designed to withstand. 

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Metal expansion joints are also required when it comes to absorbing different vibrations produced by motors, compressors or turbines; various axial, angular and lateral movements can be easily stabilized in almost all situations.

Metal bellows is a cylindrical container or vessel that can be stretched or compressed on account of several circular folds. They are flexible and durable when they are properly used, meaning if they are used in the specification is designed.

Metal bellows are used in various industries, especially because they can perform many distinctive functions from sealing environments to carrying gases, liquids, and sludge.