Types and Styles of Expansion Joint Rubber

Expansion joint rubber is a material used to compensate for axial (compressive), lateral (shear) and angular (bending) deflections within the joint body. It also allows the movement of fluids and materials to flow through it without affecting its serviceability.

There are a variety of types and styles of expansion joints available, each designed to meet different needs. They vary in terms of material, pressure ratings, markings, and special options.

The most common type of expansion joint is the spool-type. The spool-type expansion joint is a hand-built product designed to meet exacting specifications for tube and cover requirements, pressure ratings, and markings. It has an arch construction that can be fabricated using a variety of elastomer products, including EPDM, Chlorobutyl, Neoprene, Nitrile, Hypalon, and Viton. When needed, a white PTFE liner can be added.

Another type of expansion joint is the double-arch type. These are precision-molded to handle both lateral and angular movements. They are typically used to control vibration in piping systems with large or heavy movement. They are often utilized in applications with process fluids that have suspended solids in the pipe.

These type of expansion joints can be made with single spheres or double spheres to absorb greater pipe motions. They are commonly installed in HVAC ducting or water conveyance in boilers to absorb vibration from mechanical equipment that is connected to the pipeline.

For more complex piping situations, the double-arch style of expansion joint can be built with multiple arches to take up even greater movements. These types of joints are most frequently used in industrial and commercial boilers, HVAC ducting, and other large-scale facilities.

In smaller piping systems, the union ends of a rubber expansion joint offer an easy way to disconnect the piping to service equipment such as pumps. This design is chemical and abrasion resistant to accommodate for higher pressures than standard metal expansion joints and eliminates sediment buildup.

The MJ-70 and MJ-80 series of molded elastomer double-arch expansion joints feature a precision molded elastomer compound reinforced with multiple plies of nylon. The spherical shape provides a smooth, low turbulence flow that can handle process fluids with suspended solids.

These double-arch molded elastomer expansion joints can be built with a number of special features to ensure the best possible performance in your application. For example, the MJ-80 joint is available with a floating flange to facilitate alignment of bolt holes. This is especially beneficial when the flanged ends are to be fitted on plastic pipe.

TANIQ uses its digital FE software to simulate and optimize the production process. This helps to ensure that each step is properly executed and that all necessary parts are produced in the desired timeframe.

In addition, TANIQ’s software can be used to monitor and track the status of each individual part as it leaves the production line. This can be helpful when resolving any problems during the manufacturing process and preventing costly downtime.

The majority of rubber expansion joints are manufactured by manually wrapping of individual cords and rubber strips around a bellows-shaped product mandrel. In order to improve the production process, a series of new automation techniques has been developed. These techniques are able to speed up the production of expansion joints by 60% while maintaining a high level of quality and accuracy.