The non-metallic expansion joint skin is a key component in non-metallic expansion joints, it is a composite layer of various high-performance non-metallic materials to absorb axial, lateral or angular displacements in piping systems while providing the necessary sealing and resistance to media corrosion. The design and material selection of the skin depends on its working environment and intended function. Here are some of the main features and components of the skin:
Skin material:
Silicone rubber: Suitable for hot air ducts and applications requiring low temperature flexibility, resistant to ozone and climate influences, but not suitable for highly corrosive media.
fluororubber: Suitable for chemical, oily and high-temperature corrosive media.
Ethylene propylene monomer (EPDM): Good tensile strength and elongation, suitable for a wide range of temperatures.
Neoprene rubber: Suitable for oily media, with wear resistance, impact resistance and flexure resistance.
chlorosulfonated polyethylene: It has good tensile strength, elongation and resistance to acidic media.
Silicone cloth and fluorine cloth: These materials have good resistance to high temperatures and chemical corrosion.
Skin Structure:
Airtight layer: Prevent gas or liquid leakage 。
Outer protective layer: Protects the inner layer from external physical damage.
insulation layer: Reduces heat loss or prevents condensation in high or low temperature applications.
Support layer: Provides structural strength and stability.
cladding: Protects the entire skin from environmental factors.
Additional Features:
Pressure and temperature tolerance: Some non-metallic skins can withstand pressures up to 4000 bar, and the operating temperature can be customized by telephone for details.
Reinforcement layer: Usually constructed of high-strength steel wire or other fibrous material to increase the mechanical strength of the skin.
Inner and Outer Adhesive Layers: Use materials such as polyoxymethylene (POM), polyamide (PA) or polyurethane (PUR), respectively, to provide chemical protection and wear resistance.
Connector: Carbon steel or stainless steel material is used, and advanced buckling technology is adopted to ensure the connection strength.
The selection of a non-metallic expansion joint skin must take into account the nature of the working medium, operating temperature, pressure, corrosiveness, and the type of displacement compensation required. The correct selection of skin material is essential to ensure the long-term reliability and performance of the expansion joint.