Abstract: A control valve includes a valve body defining a top opening. A bonnet is provided for closing off the top opening of the valve body. A stem housed in the bonnet and the valve housing slidably moves a valve plug in the valve housing to open and close the valve. A packing assembly is provided for sealing between the stem and bonnet, and a packing retainer maintains the packing assembly within the bonnet. A retainer ring is provided for securing the packing retainer in place. The retainer ring can be formed as a generally cylindrical ring that engages the packing retainer and can be tightened on the packing retainer. Outer notches formed in an exterior surface of the lock nut provide for tightening of the lock nut with a tool. In addition, the retainer ring may include a lower portion that closely receives an outer surface of the packing retainer, thereby to center the retainer ring with the packing retainer.

Abstract: A seal assembly is adapted for use in a valve having a trim cage with an inner surface extending along an axis and a plug sized to fit inside the trim cage inner surface, wherein the plug is adapted to move along the axis. The seal assembly includes a spring-loaded seal ring disposed between the plug and the trim cage inner surface, the seal ring including a center spring member and a jacket formed of a fluoropolymer resin to tightly seal between the plug and the trim cage inner surface. A first wiper ring is disposed between the plug and the trim cage inner surface and positioned axially upstream of the seal ring, and a second wiper ring is disposed between the plug and the trim cage inner surface and positioned axially downstream of the seal ring. Each of the first and second wiper rings has an outside surface sized to engage the trim cage inner surface and is formed of a material sufficiently rigid to scrape foreign material from the bore surface yet sufficiently soft to minimize damage to the bore.

Abstract: A seal assembly is adapted for use in a valve having a trim cage with an inner surface extending along an axis and a plug sized to fit inside the trim cage inner surface, wherein the plug is adapted to move along the axis. The seal assembly includes a spring-loaded seal ring disposed between the plug and the trim cage inner surface, the seal ring including a center spring member and a jacket formed of a fluoropolymer resin to tightly seal between the plug and the trim cage inner surface. A first wiper ring is disposed between the plug and the trim cage inner surface and positioned axially upstream of the seal ring, and a second wiper ring is disposed between the plug and the trim cage inner surface and positioned axially downstream of the seal ring. Each of the first and second wiper rings has an outside surface sized to engage the trim cage inner surface and is formed of a material sufficiently rigid to scrape foreign material from the bore surface yet sufficiently soft to minimize damage to the bore.

Abstract: A control valve includes a valve body defining a top opening. A bonnet is provided for closing off the top opening of the valve body. A stem housed in the bonnet and the valve housing slidably moves a valve plug in the valve housing to open and close the valve. A packing assembly is provided for sealing between the stem and bonnet, and a packing retainer maintains the packing assembly within the bonnet. A retainer ring is provided for securing the packing retainer in place. The retainer ring can be formed as a generally cylindrical ring that engages the packing retainer and can be tightened on the packing retainer. Outer notches formed in an exterior surface of the lock nut provide for tightening of the lock nut with a tool. In addition, the retainer ring may include a lower portion that closely receives an outer surface of the packing retainer, thereby to center the retainer ring with the packing retainer.