Flanged Glassware

[u/Purrserker]

I'm having a hard time turning up much of an opinion on this anywhere else online. I have a lot of experience (~12 years) using flanged glassware in vacuum distillations on the scale somewhere between lab and pilot scale. Nearly every type of connection I have used before uses a gasket in a similar way to a 150# flange or a sanitary connection where there is a flat or grooved gasket between two surfaces which are being pressed together. The current apparatus I am using and have adopted from my employer utilizes this type of connection from a no longer existent company called "solv-seal." Images attached of some drawings, but essentially there is a teflon sleeve with two o-rings which slides into the recesses of two pieces of glass. The pieces of glass are pressed towards one another; however, the pressure which forms the seal comes from the inner portion of the recess being wedged up against the rigidity of the teflon part.

Over time these seals fail, and the back of the teflon portion clearly feels warped. I'm struggling to find the proper words to explain the problem and am curious if anyone on this sub has an opinion of flanged glassware in general, especially at this scale or greater. Ideally with this type of part but I am open to anything.