Flange gaskets are highly engineered products, and their performance depends on many factors. Certainly design, manufacture, installation, and process conditions are all critical, but so is storage before use. Gasket materials often remain in storage for a long time before they are placed into service. Unfortunately, storage practices for gasket materials are generally not optimal or controlled well enough. This article provides guidance for the storage of different gasket materials to preserve their integrity.
Gasket materials are divided into three main categories: non-metallic, semi-metallic and metallic. Non-metallic gaskets, or soft gaskets, are fabricated from materials such as rubber, fiber, polytetrafluoroethylene (PTFE) and graphite. The material properties make them ideal for flat-faced applications with low pressures. Metallic gaskets are fabricated from one or a combination of metals. Semi-metallic gaskets are composed of metal and non-metallic materials. The metal is intended to offer strength and resilience while the non-metallic components provide conformability and sealabililty. These types of gasket are used in higher-pressure applications. The most common semi-metallic gaskets are spiral wound gaskets.