A Single Metal Expansion joint is the simplest type of metal expansion joint with single bellow construction welded or flanged to end fittings. The single bellows can absorb any combination of basic movements in pipeline where there are proper anchors and guides.

A Universal Double Metal Expansion Joint consists of two bellows connected by a center tube, welded or flanges to pipe ends. The universal arrangement allows greater axial, lateral and angular movements than a single expansion joint. Increasing the center spool length produces increased movement capability.

A Tied Double Metal Expansion Joint consists of two bellows connected by a center tube piece with tie rods. The tie rods are connected to the restraining flanges through spherical washers which allow for movement between the tie rods and the flanges during operation. This type of expansion joint can accommodate large movements in the lateral plane and can operate in any direction.

A Gimbal Metal Expansion Joint is designed to absorb pressure thrust and angular rotation in any plane by two pairs of hinges connected to a common floating gimbal ring. The gimbal ring, hinges and pins must be designed to restrain the thrust of the expansion joint due to internal pressure and extraneous forces.

A Hinged Metal Expansion Joint contains one bellow and is designed to absorb angular rotation in one plane only by one pair of hinges. The hinges and hinge pins must be designed to restrain the thrust of the expansion joint due to internal pressure and extraneous forces. Hinged expansion joints should be used in sets of two or three bonded to absorb combinations of movements in the piping system.

A Pressure Balanced Metal Expansion Joint is designed to absorb axial movement and/or lateral deflection while pressure loading upon piping or equipment is considered excessive or objectionable. Pressure Balanced Metal Expansion Joints restrain the pressure thrust through tie devices, where two bellows are used in the flow end and a single bellow in the balancing end.

The External Pressurized Metal Expansion Joint is designed that the pressure is acting to the bellows externally while the inside of the bellows is at atmospheric pressure. It has many convolutions to allow a large amount of axial movement. But under external pressure the bellows will retain its shape completely stable.

Rectangular Expansion Joint may be subjected to axial movement, angular movement, lateral deflection or any combination of these occurring at the interface of bellows and the associated ducting system.