GASKET AND TYPES OF GASKETS
A gasket, also known as a flange gasket, is used to make up a static seal between two flange surfaces under different operating conditions, with different pressure and temperature. A flange gasket fills irregularly small gaps in the surface of the flange, and then it creates a seal to prevent liquid or gas in the pipe from leaking to the outside. Regarding Correct use and installation of flange gaskets is mandatory in flange connections.
Types of flange gasket
The ASME B16.20 standard specifies types, sizes, materials, dimensions, dimensional tolerances, and markings for types of gasket
Based on the material of the gasket, it is divided into 3 main types:
+ Non-metallic gasket types
+ Semi-Metallic gasket types
+ Metallic gasket types
NON-METALLIC GASKET
Non-metallic gasket (non-metallic gasket) is usually stamped from composite material sheets manufactured from aramid fiber, glass fiber, elastomer rubber, Teflon® (PTFE), graphite, ... used for flanges in low-pressure applications.
The full-face gasket is suitable with flat-face flanges; the Flat-ring gasket is suitable with
raise-face flanges.
SEMI-METALLIC GASKET
The semi-metallic gasket is a composite of metals and non-metals. Metals provide strength, durability, pressure resistance, resilience, gasket shape retention, non-metals provide sealing and are compatible with flange surfaces. Semi-metallic gaskets are commonly used as spiral wound gaskets, camprofile, metal-reinforced graphite gaskets.
The semi-metallic gasket is designed to suit most high pressure and temperature operating conditions and flange surface types: raised face, male-and-female face, and tongue-and-groove face.
METALLIC GASKET
Metallic gaskets are made from metal or alloy of the desired shape and size. Commonly used metal gaskets are ring type joint gasket (RTJ), which is a special, suitable, guaranteed, reliable sealing choice.
Ring type joint gasket made of soft metal material, placed in the available groove between the 2 flange surfaces, by applying pressure through the bolt tightening force, the softer metal material will deform and fill clearances between flange surfaces, creating a tight and effective seal.
