Substrate
A water-proof protective coating, made of natural or synthetic rubber without junctions, which extends all the expansion joint’s length to the outer edge of its flanges. Its main feature is removing the possibility for the fluid to penetrate and weaken the joint body. It is designed to satisfy service conditions in the presence of chemical and petroleum products, wastewater, abrasive and gaseous materials.
Fabric reinforcement
Fabric reinforcement is the flexible and supporting element between the substrate and covering. The standard construction expects high-quality synthetic fabrics. In case of specific temperature and pressure it is possible to use other suitable materials. All the layers of fabric are impregnated with rubber or synthetic combinations to keep flexible the surface even between more adjoined layers.
The “Carcass”
The “carcass” or the joint’s body is made of fabric and a metal reinforcement, if necessary.
Covering
The outer surface of the join is made of natural or synthetic according to the operational needs. The main function of covering is to protect the joint’s body from external damages, special polymers can be used to resist to chemical products, oils, sunlight, acids, and ozone fumes. An extra coating can be placed on the outside of the joint to increase its protection.
Metal reinforcement
Steel wires or rings placed inside the joint’s body, are frequently used as reinforcing elements of the joint. Their function is to grant the joint the proper resistance to the operating and/or vacuum condition.