Abstract: Flexible seals for process control valves are disclosed. An example disclosed seal includes a substantially flexible ring-shaped carrier configured to be fixed within the butterfly valve and to surround a flow control aperture therein. The seal also includes a substantially rigid seal ring that has an outer circumferential surface fixed to the substantially flexible carrier and an inner circumferential surface configured to sealingly engage a control member that operatively interacts with the flow control aperture.

Abstract: An apparatus for sealing an operating member of a sliding or rotating assembly includes a seal formed by a composition of materials. A plurality of abrasive particles are incorporated into the composition and thus positioned within the seal. The abrasive particles are disposed to remove an amount of material adhering to the operating member, caused primarily by graphite adhesion. The composition forming the seal can be in the form of a laminate structure, and made of graphite, or graphite and polytetrafluoroethylene (“PTFE”). The plurality of abrasive particles can be selected to be suitable for removing material, while not substantially damaging a surface of the operating member.