Understanding Flange Gasket And Features
A Flange Gasket is a seal to prevent leaking of fluids. You must have seen the rubber bush used in pipelines. All of them fill irregularities between two mating surfaces. All the gaskets, including Flange Gasket; often produced by sheet materials. O-ring, fiber washer, paper gasket, and cylinder head gasket are the seals and gaskets widely being used today for many applications. Metal gaskets are there, but most of the time; a material that can deform is the choice for Flange Gaskets. Well, that’s because the gasket should deform itself to fill irregularities between two mating surfaces.
Gaskets come in different sizes, shapes, with holes, and without holes. For some gaskets, a sealant is required to seal properly. Some piping gaskets are there entirely made of metals.
Flange Gaskets properties: As mentioned, a gasket has to deform up to some extent for proper sealing. So, most of the gaskets are made of a flat material. Rubber, paper, metal, silicone, felt, cork, nitrile rubber, fiberglass, neoprene, Teflon, and plastic polymers are the material selections for gasket types. Industrial gaskets should be able to withstand high compressive loads up to 14 Mpa. as you can see in the picture, the bolts exert a massive compressive load on the gasket. So, can you use a fragile material for gaskets? No, right? In other words, you must choose the right type depending on the compressive load. Die cutting, water jet, flash cutting, and hand cutting are the methods used to cut Flange Gaskets in shapes. Die cutting method is the least accurate, but used for quantity orders. Flash cutting and water jet are very accurate methods compared to die cutting and hand cutting.
Fiber and rubber gaskets: Compressibility is an essential property of the materials used for Flange Gaskets. Anyway, that doesn’t mean that every gasket needs rubber materials for flexibility. Fiber materials are the alternatives for rubber. Fiber materials use a process similar to papermaking. Fiber strands and resin form fiber sheets, and from the sheets; they cut gaskets. The advantage of using fiber materials is that you can use different fibers to produce Flange Gaskets of different strengths. They can be vegetable fibers and aramid materials that can withstand high temperatures and compressive loads. Adding cork or a rubber binder enhances the compressibility. Flange Gaskets made of fiber materials are both lightweight and hard.
Vegetable fiber gasket is the oldest type still being used for many applications. The tensile strength of fiber gaskets is higher compared to other types. Also, they can withstand temperatures from 250–350°F. High resistivity to chemicals such as oil makes them suitable for industrial applications. The ring-type and the full-face are the two types of Flange Gaskets used for many applications. Also, they can be further categorized as Sheet Gaskets, Corrugated Metal Gaskets, Ring Gaskets, and Spiral Wound Gaskets.
Some final words: Stress relaxation and torque loss, unevenly distributed pressing force, and surface not smooth are the common reasons for failure (according to Wikipedia.) Many types of gaskets are there, and Flange Gasket is the type used for sealing two mating pipes. Fiber materials enhance the tensile strength of gaskets, so widely used for high compressive and temperature applications.