An expansion joint is a mechanical joint that extends between two pieces of material. Its components include an outer ply and an inner ply. Excessive vacuum in the application process can cause the inner ply of the rubber to separate from the body of the expansion joint. This is a common problem and should be avoided if possible.
EPDM rubber expansion joint connectors consist of a high-quality EPDM rubber tube and rubber cover, reinforced by a nylon tire cord. EPDM is a superior elastomer over Neoprene and Nitrile, and their physical and temperature properties make them a superior choice for these types of connectors. Unlike Neoprene, EPDM rubber connectors feature galvanized steel floating flanges, which engage the rubber beaded end of the expansion joint and rotate easily for speedy installation.
As an essential component of a piping system, an expansion joint provides protection from movement induced by thermal expansion and contraction, as well as mechanical vibrations of the connected pipeline. A rubber expansion joint is a versatile, high-performance component, which can withstand pressure pulsations, axial and lateral movements, and can withstand high temperatures and pressure.
A compression seal for an expansion joint is a rubber compound inserted into a joint. The seal has a double barrier inflated construction that prevents movement and is resistant to minor irregularities in the joint face. The seal’s interior webbing is complex and rigid to resist differential deflection. The joint is capped with an elastomeric concrete nosing which mechanically anchors the seal.
Neoprene Compression Seals are manufactured using poly-chloroprene compounds and must meet specific requirements set out by ASTM D3542. They are suited for a variety of applications including driveways, buildings, sidewalks, and stadium ramps. They are also used for bridges, highways, and water treatment plants.
A multiple arch expansion joint uses two or more arches of rubber to expand and contract. These joints are ideal for processes where large movement is needed. Their unique design provides twice the all-directional movement capability and half the spring rate of a single-arch design. They also feature a seamless cover for noise and vibration reduction.
These joints have a stiff rubber face flange and are typically made of two or four standard-sized arches. The look at this now arches are molded into an arch and are supported by wire or metal rings. For longer-length joints, multiple wide arches may be used. They are constructed with an integral flange and have mounting holes to match the flanges of the pipework. Because of this, they form a tight seal without using gaskets.
Externally pressurized expansion joints are a flexible solution for large system movements that are difficult to accommodate by conventional axial expansion joints. Their unique design is based on a bellows that absorbs fluid pressure from the outside and is stabilized by an external pressure that acts on the bellows’ gap. External pressure also helps the bellows remain more rigid, allowing them to withstand larger axial movements.
The expansion joint carcass is made of a fabric or synthetic rubber and interior metal reinforcement. The fabric provides support for the joint’s movement and pressure, while the wire or solid rings embedded in the carcass help it withstand pressure. The expansion joint also contains a leak-proof lining tube that extends from the bore to the outside edges of the flanges.
METRAFLEX manufactures a variety of expansion joints for the construction industry. These rubber-based joints are made to handle extreme pressure and temperature ranges, reducing the number of joints and anchors required to support the expansion. These joints can be customized to fit your specifications. They are also available in custom sizes and can be repacked while in use.