Style BG-1

This style utilizes an external ring which accurately centers gasket on Flange face and provides additional radial strength to prevent gasket blow-out and acts as a compression stop .
A general purpose of gasket is for application with flat face and raised face flanges up to class 2500#. Above class 600, an internal ring is recommended.

Style BG-2

This kind consists of an inner and outer ring , possessed of high heat and corrosion resistance in order to prevent flange erosion . This style is fitted with high temperature and pressure conditions (class 900# and higher ) or in services with erosive flow.

Style BG-3

Basic construction type. This style of spiral wound gasket with no accessory ring (no inner/outer ring ) is suitable for tongue and groove , male and female or grooved to flat face assemblies.
Inner and outer diameter are reinforced with several plies of metal without filler to give geater stability and better compression and sealing characteristics.