Hardware & Seals
Centering ring assemblies are the heart of an ISO flange's sealing mechanism. Each centering ring assembly is constructed from 2 pieces: 1) a metallic alignment ring and 2) an elastomeric o-ring. Alignment rings are manufactured from 4 materials: 304L stainless steel, 316L stainless steel, aluminum, and brass. O-rings are produced from 3 elastomers: Viton®, Buna-N, or silicone. Centering ring assemblies with a (72 mesh) screen are designed for those applications where particulates may be generated. Adaptive centering ring assemblies are used to convert rarely used ISO-QF flange sizes (10, 20, 32) to more commonly used flange sizes (16, 25, 40). Over pressure rings are an optional item used to prevent an ISO-QF o-ring from becoming unseated or "blown out" in vacuum systems experiencing intermittent positive pressures.