The Main Types of Isolating Flange Kits are:
VCS
A high reliability gasket used mainly for isolating purposes in Very Critical Services.
VCFS
A Very critical fire safe version was created by taking a standard VCS configuration and adding a secondary sealing element that is capable of maintaining a seal while subject to a 15000F fire. The VCFS had fully passed the API 6FB, 3rd Edition fire test.
VCSID
A Very critical service Inside Diameter Seal introduces an internal, machined PTFE seal at the bore of the existing VCS design platform to ensure an extremely tight seal and a resistance to effects from internal pressure or aggressive media.