Control valve having "C" seal

A control valve comprising:

• a valve body having a first portion, a second portion, and a flow passage extending between the first portion and the second portion;
• a generally cylindrical seat defined adjacent the second portion;
• a generally cylindrical valve cage mounted within the valve body so as to be at least partially disposed in the flow passage, the valve cage having a first end fixedly secured to the valve body and a second end sized to be disposed adjacent the seat;
• a retaining ring sized for insertion within the valve body, the retaining ring and the flange spaced apart to form a gap;
• and
• a seal disposed in the gap at an interface between the seat and the second end of the valve cage, the seal having a C-shaped cross-section.

A control valve having a shiftable valve plug and comprising:

• a valve body having an inlet, an outlet, a flow passage extending between the inlet and the outlet, and defining a longitudinal axis;
• a generally cylindrical valve cage disposed within the valve body and sized to receive the valve plug, the valve cage including at least one aperture comprising at least a portion of the flow passage, a portion of the valve cage disposed adjacent a portion of the valve body at an interface;
• a seal having a C-shaped cross section disposed at the interface between the valve cage and the valve body;
• and
• a retainer disposed adjacent the interface and positioned to secure the seal against movement along the longitudinal axis.