Maxi-Joint Technical Guidelines and References

Maxi-Joint is a brand under General Rubber Corp. representing our comprehensive line of expansion joints, flexible connectors, rubber flanged hoses and related accessories, as well as spray shields and penetration seals. These products provide critical functions in piping and ducting systems.

Since our inception in 1950, General Rubber Corp. has designed and developed a wide range of mechanical rubber products used in the most demanding applications. Rubber is one of the most compliant and resilient materials available. This not only makes it an ideal material for car tires, but also for expansion joints and flexible connectors. With a flexing cycle life in the tens of millions, fatigue is simply not a design concern. Improved performance and engineered solutions are often accomplished by incorporating advanced materials and technologies to what otherwise would be considered a conventional product line. This benefits both the specifying engineer designing an optimal system, as well as the customer performing maintenance on, or upgrading an aging system.

Piping and ducting systems require support and flexibility as critical design elements. The obvious consequence of inadequate support is catastrophic system failure that can also be life threatening. It is less obvious however, that inadequate flexibility can produce the same devastating consequences. System flexibility is required to absorb thermal movements, ground settlement, misalignment, vibration and shock. The features and benefits of our expansion joints include absorbing these forces and displacements, and replacing them with the expansion joint’s low stiffness (spring rate). In addition, our products absorb noise and vibration, as well as provide easy access to piping and equipment. Applying expansion joints to your system is the subject and title of the linked article published in Pumps and Systems magazine. It remains a good reference for understanding piping system requirements and basic expansion joint functions, including the role of control units in anchored and un-anchored systems.

Improved performance is directly related to our materials of construction and design. We utilize industry leading construction materials including premium elastomeric compounds, tire cord and high tensile steel reinforcement. Utilizing tire cord is a good example of optimizing a design with advanced materials. The tire cord is engineered with a Resorcinol-Formaldehyde Latex (RFL) coating for superior bonding to the rubber. The cords themselves can be aligned on an optimal bias ply angle, offering tailored strength in the directions needed. This virtually eliminates delamination and reduces the total number of plies required. The result is improved performance in the form of increased movement capability and decreased spring rates, as well as improved reliability. New design features in piping expansion joints is the subject and title of the linked paper presented at The American Power Conference. It also remains a good reference for understanding the incredible performance improvements that can be achieved when advanced materials and technologies are utilized.

Engineered solutions are also directly related to our many years of experience and understanding of demanding applications. For example, supplying high pressure and self retracting expansion joints on offshore mooring platforms provided us with the understanding to do the same on a massive scale for the CCWP project in Qatar. This project required hundreds of much larger diameter high pressure dismantling expansion joints. We are proud of an environmental award we earned from the Fluid Sealing Association and Chemical Engineering magazine for submitting the linked case study on this project. Similarly, supplying original equipment into many nuclear power plants has also provided us with the opportunity and ability to upgrade both metal and rubber expansion joints for higher performance and greater reliability. In general, replacement and retrofit work often requires building the product to existing field dimensions, including permanent offsets caused by ground settlement, unrestrained thrust forces or equipment substitution. The custom fit unit is easier to install and will have a longer maintenance free life. Utilizing improved materials and designs will also improve the product's service life and reliability as well. We are experienced at obtaining the relevant field information and producing an optimal product for that application.

Maxi-Joint expansion joints and flexible connectors provide critical design elements in piping and ducting systems. The experience and capability of General Rubber can effectively utilize these products in even the most demanding applications. In consideration of our products, you are assured that every aspect of your project will be our priority.

Thank you for your consideration.