Heat Exchanger Materials

Plate Heat Exchanger Gasket Material

For plate (and frame) heat exchangers, the standard materials are EPDM and Nitrile rubber (NBR). EPDM is used normally for non-fatty/oily applications, and NBR for oil/fat applications. However, there are no rules without exceptions. An "oil" and fatty application may have a low fat content, making the application more suitable for EPDM instead of NBR.

Other rubbers used for PHE's are Hydrogenated Nitrile Rubber (HNBR), Fluorocarbon rubber (FKM), Butyl, Chloroprene Rubber (GR), Chlorsulphonated Polyethylene (CSM), Styrene Rubber (SBR), Natural Rubber (NR) and Silicone Rubber (Q) are less common ones.

Lifetime

Eventually all rubber materials will degrade, loosing their properties, making them unsuitable for further use. It is all a matter of time and the original quality of the product. The lifetime of rubber products is dependent on the environment (chemical types, concentrations) and temperature. Also, temperature changes and pressure changes effect the performance and lifetime of the rubber product.

Chemical Resistance

Each rubber material has its unique resistance towards various chemicals. Polymer used, as well as additives, effect which chemicals each rubber material is suitable for. WCR compounds rubber materials for optimum performance.

High Temperature

At high temperatures the rubber will be attacked faster by the chemicals in use, and the surrounding oxygen. The oxidation process will either make the rubber harder (the most common one) OR make it softer (less common), OR both at the same time. Either way the change in properties will reduce the performance. All rubber materials have a maximum continuous temperature, which should not be exceeded to maintain good performance and to achieve a reasonable lifetime.

Low Temperature

At low temperatures the stiffness increases, and the elasticity decreases. This influences the sealing force of the gaskets. All rubber materials have a certain lowest temperature that have to be exceeded to be able to perform well enough as a gasket.