Integrated circuits are in all sorts of devices, from the toaster that made your breakfast this morning to the computer or smartphone that’s allowing you to read these words.

Centering ring assemblies are a critical part of any ISO sealing solution. Centering rings align the two mating flanges during the seal assembly and clamping process as well as providing structural support for the elastomer sealing ring.

In the semiconductor and vacuum industry, there are 13 common flange sizes that fit most equipment. As such, there are associated standard AS-568 O-Rings that fit those flanges. This guide shows flange sizes alongside the 300 series or 400 series O-Ring.

ISO-QF Bored Weld flanges are manufactured in 304 and 316 stainless steel. QF flanges are sexless, infinitely rotatable, and fastened with quick clamps that compress an elastomer O-Ring held in a centering ring between two flange faces to create a high vacuum seal.

The ISO-LF (KF) Blank Flange is an ISO standard-sized flange that attaches onto other components in the ISO family. Blank flanges are manufactured with no weld prep and no tubing bore and typically come in 304 stainless steel or 6061 Aluminum.

The CF (ConFlat) flange is the most popular and widely used flange for high vacuum and UHV applications. Many gauges, instruments, accessories, and feedthroughs are available on this system.

An ASA Fixed Flange is a one-piece design that comes in both bored and blank with a set bolt hole orientation.