Abstract: A fluid end including a cylinder has a bore extending therethrough. A plunger is reciprocally disposed in the bore. A packing element is disposed in the bore to seal the annular space between the plunger and bore and includes a lubrication ring formed of metallic fibers and impregnated with a solid lubricant, a seal ring formed of a high-lubricity polymeric material, and means for positioning the lubrication and seal rings in the bore.

Abstract: A fluid end for use in high-pressure, reciprocating, fluid pumps has a cylinder with a bore therethrough in which a plunger reciprocates. A valve body is disposed at one end of the bore and includes suction valve seat and a discharge valve seat, which are substantially coaxial with the axis of the bore in the cylinder. The suction and discharge valves include elastomeric, abrasion-resistant seal members. The valve body is provided with at least one fluid flow passage positioned about the periphery of the suction valve seat to permit purging of entrapped gas from the pressure chamber defined in the cylinder bore between the plunger and the valve body. In a preferred embodiment of the present invention the suction and discharge valves are identical and interchangeable, and the valves are provided with urethane seal members to increase the abrasion resistance of the valves.