How to Choose Between Metallic and Non-Metallic Gaskets

28 February 2020

Different industries have been using gaskets to fill in the space or gap between two or more mating surfaces. Gaskets are generally included in numerous applications since they can prevent any leakage from or into the joined objects while under compression. They can also withstand high compressive loads, which can assure the longevity of the involved mating surfaces.

Gaskets have different types according to their properties. Some gaskets can work under extreme temperatures that make them suitable for specific situations. Other gaskets, however, can tolerate exposure to highly corrosive fluid. All these properties may vary on each gaskets depending on the material used for their fabrication.

Some materials that are used in making gaskets include paper, rubber, silicone, metal, felt, fibreglass, and plastic polymers. Since the overall properties of gaskets rely heavily on the materials used, let’s dive deeper into the subject of metallic and non-metallic gaskets.

Choosing Metallic Gaskets

As the name implies, metallic gaskets are fabricated from either a single metal or an alloy, a combination of metals. The properties of metals allow higher-quality surface sealing of gaskets when compared to non-metallic gaskets. Since they can naturally resist extreme temperatures, pressure, and chemical exposure, metallic gaskets are now widely used for medium- and high-pressure applications. High-temperature applications also utilise metallic gaskets.

The most popular variety of metallic gaskets is the ring-type-joint (RTJ) type. This type of gasket features a solid metal ring construction that comes in different cross-sections like oval, round, and octagonal. This same gasket has a passage hole that allows equalisation of pressure on both sides of the surface sealing. Other types of the metallic gasket are grooved gaskets, spiral wound gaskets, corrugated metal gaskets, and metal-jacketed gaskets.

Metallic gaskets are normally used in offshore oil and gas pipelines. They can also be used in heat exchangers, compressors, pumps, manholes, valves, and turbines.

Choosing Non-Metallic Gaskets

Non-metallic gaskets, on the other hand, are made from composite materials like glass fibre, mica sheet, ceramic fibre, elastomeric and fibre sheet, and compressed non-asbestos sheet. One great advantage of non-metallic gaskets over the metallic ones is that they have superior corrosion resistance. They can also be easily compressed under bolt load. However, this type of gasket cannot tolerate extreme levels of temperature and pressure.

Flat-face and raised-face flanges are the common companions of non-metallic gaskets when used in low-pressure applications. To be specific, full-face non-metallic gaskets are great for flat-face flanges, while flat-ring gaskets are suitable for raised-face flanges.

As mentioned, low-pressure applications benefit the most with non-metallic gaskets. Some low-pressure applications of non-metallic gaskets are pipe flanges, compressors, heat exchangers, and bonnet valves.

If you need a gasket that can work under extreme temperature and pressure, then you must choose the metallic ones. Alternatively, you must pick non-metallic gaskets if you will be using them with highly corrosive elements. To know more about these gaskets, you can talk to us at Gasketech.

Optimized by: Netwizard SEO