Rubber Expantion Joint – Construction Details
A protective, leak proof lining made of synthetic or natural rubber as the service dictates. This is a seamless tube that extends through the bore to the outside edges of the flanges.
Tube
A protective, leak proof lining made of synthetic or natural rubber as the service dictates. This is a seamless tube that extends through the bore to the outside edges of the flanges. Its purpose is to eliminate the possibility of the materials being handled the carcass and weakening the fabric. These tubes can be designed to cover service conditions for chemical petroleum, sewage, gaseous and abrasive materials.
Cover
The exterior surface of the joint is formed from natural or synthetic rubber, depending on service requirements.
The prime function of the cover is to protect the carcass from outside damage or abuse. Special polymers can be supplied to resist chemi- cals, oils sunlight, acid fumes and ozone. Also, a protective coating may be applied to the exterior of the joint for additional protection.
Carcass
The carcass or body of the expansion joint consists of fabric and, when necessary, metal reinforcement.
Fabric Reinforcement
The carcass fabric reinforcement is the flexible and supporting member between the tube and cover. Standard constructions normally utilize high quality synthetic fabric. Other suitable fabrics can also be used at some specific pressures and temperatures. All fabric plies are impregnated with rubber or synthetic com- pounds to allows flexibility between the fabric plies.
Metal reinforcement
Wire or solid steel rings embedded in the carcass are frequently used as strengthening members of the joint. The use of metal some- times raises the rated working pressure and can supply rigidity to the joint for vacuum service.
Test
Characteristics and performance of rubber compensator can be verified with special toolings simulating real operation situation. Following pic are showing some devices used for:
- pressure test
- lateral deflection test
- cycle stress tes