They usually are connected with fasteners like bolts and are a good method for creating secure connections, but they often are not fluid-tight without being fitted with gaskets.
Flange connections can be irregularly shaped or subject to stress. In these cases, a gasketing solution that provides flexibility while maintaining its seal is necessary. In response to this problem, engineers developed spiral wound gaskets, which combine the structural strength of metals with the sealing abilities of softer filler materials like elastomers and graphite.
Gas pipes, tubing and other networks of transmissive channels can all make use of spiral wound gaskets. Pumps, valves, thermal exchangers and many other components and control equipment for gas and liquid transmission systems can also make use of spiral wound gaskets.
Spiral wound gaskets perform particularly well in high temperature and high pressure applications, making them ideal sealing solutions in the context of pressurized gas and liquid transmission. Because they offer qualities of both strength and flexibility even when exposed to harsh conditions, spiral wound gaskets have become a popular gasketing solution.
There are a number of different spiral wound gasket configurations, but they all follow the same basic concept. Some models are manufactured by winding several plies of metal and several plies of soft filler around each other, offering both the strength of the metal and the flexibility and sealing qualities of the filler.
Other models feature only metal plies in a circular configuration attached to an outer ring of soft filler. Other designs can feature alternating rings of metal and filler, though these are less common.
Every spiral wound gasket must be carefully fitted to the contours of the pipes, hoses or other equipment that they will be used to seal. Also, the gasket’s composition must not interfere with the operation of the equipment they seal.
Most gaskets are made of stainless steel, which causes few issues in terms of reactivity with transmitted chemicals. The filler materials, which can range from graphite to polytetrafluoroethylene, must be chosen more carefully based on their qualities of flexibility, durability, chemical reactivity and operational lifespan.