Patent ID: 8550117

Claim:
A seal assembly for a fluid pressure control device having a body defining an inlet, an outlet, and a fluid flow path extending from the inlet to the outlet, the seal assembly comprising: a guide element coupled to the body, the guide element comprising a center bore defining a packing chamber, a neck having a diameter less than a diameter of the packing chamber, and a receptacle located on an opposite side of the neck from the packing chamber, a packing assembly defining a sealing surface positioned within the packing chamber, and a bearing ring comprising an interior surface positioned within the receptacle; and a throttling element assembly comprising a throttling element positionable within the flow path and a stem coupled to the throttling element, the stem having an exterior sealing surface with a first portion and a second portion, the second portion of the exterior sealing surface of the stem and the interior surface of the bearing ring cooperating to define guide surfaces, the sealing surface of the packing assembly forming a seal with the first portion of the exterior sealing surface of the stem; wherein a relief void is formed by an enlarged diameter portion formed in a portion of the bearing ring and adjacent the second portion of the stem.