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: A packing nut assembly for a control valve having a valve body and a valve stem includes a packing box arranged for operative coupling to the valve body and having a primary bore sized to receive the valve stem and first and second counterbores. The first counterbore is sized to receive valve packing and the second counterbore includes internal threads. A packing nut having a central bore is sized to receive the valve stem and includes a threaded outer surface positioned to engage the second counterbore of the packing box. The packing nut includes an adjustment surface positioned to face the first counterbore, and includes an adjustment head having a plurality of tool-receiving apertures sized to receive an adjustment tool.

Abstract: Collets for coupling rotary actuators to process control devices are disclosed. An example collet includes at least one flexible member having a first surface and a second surface. The first surface is configured to engage a rectangular shaft and the second surface is configured to engage a third surface of a substantially rectangular bore. The flexible member is coupled to a first end of an elongated member and configured to be displaced toward an axis of the elongated member by the third surface. The elongated member is configured to be coupled to at least a portion of a process control device actuator.

Abstract: Apparatus for increasing stiffness in a seal are disclosed. A disclosed apparatus includes a first flexible member having a curved sealing surface and a second flexible member adjacent to a retainer side of the first flexible member. The second flexible member is configured to increase a stiffness of the first flexible member in one of a plurality of flow directions.

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.