Abstract: A pressure enclosure includes a first component having an opening, a second component coupled to the first component in a position over the opening, a third component positioned between the first and second components and covering the opening, and a load chamber defined by a space between the second and third components and configured such that pressure in the load chamber biases the third component against the first component to seal the opening. The pressure enclosure may be a cylinder of a pump for pressurizing fluid or gas, with the first component a cylinder body, the second component an end cap and the third component a valve body, with the load chamber biasing the valve body against the cylinder body.

Abstract: A pressure enclosure includes a first component having an opening, a second component coupled to the first component in a position over the opening, a third component positioned between the first and second components and covering the opening, and a load chamber defined by a space between the second and third components and configured such that pressure in the load chamber biases the third component against the first component to seal the opening. The pressure enclosure may be a cylinder of a pump for pressurizing fluid or gas, with the first component a cylinder body, the second component an end cap and the third component a valve body, with the load chamber biasing the valve body against the cylinder body.

Abstract: A pressure enclosure includes a first component having an opening, a second component coupled to the first component in a position over the opening, a third component positioned between the first and second components and covering the opening, and a load chamber defined by a space between the second and third components and configured such that pressure in the load chamber biases the third component against the first component to seal the opening. The pressure enclosure may be a cylinder of a pump for pressurizing fluid or gas, with the first component a cylinder body, the second component an end cap and the third component a valve body, with the load chamber biasing the valve body against the cylinder body.

Abstract: A seal assembly for a high pressure pump where there is an O-ring positioned in a seal groove having side seal surfaces and a back seal surface, with said O-ring being exposed alternately to high and low pressures in the pumping chamber. A pressure relief passageway is provided to the O-ring at a side surface portion thereof to provide pressure relief at the back side of the O-ring and thus alleviate unwanted fluid accumulation behind the O-ring, thus extending the longevity of the O-ring.

Abstract: A seal assembly having a backup ring through which a piston reciprocates. There is a seal sleeve made of a non-abrading, extrusion resistant material that surrounds the piston at a location forwardly of the backup ring. The backup ring has an opening to receive the piston, and the opening is formed to define a radially and rearwardly expanding gas between the piston and backup ring to receive and discharge any seal material which may extrude into the gap. There is a positioning flange integral with the backup ring that surrounds the seal sleeve to press the seal sleeve into engagement with the piston, and there is an outer seal portion to form a seal between the positioning flange (or the outer portion of the backup ring) and the cylinder.

Abstract: A piston and a cylinder within a pump housing cooperate with the inner walls of the housing to form a high-pressure reservoir surrounding the cylinder to provide a continuous compressive force thereon to prevent tensile stresses in the cylinder during pumping operations to prevent failure of the cylinder due to metal fatigue. A check valve between the cylinder and the reservoir permits high-pressure fluid to flow from the cylinder into the reservoir during pumping operations to maintain substantially the maximum cylinder pressure within the reservoir. The cylinder further includes therein an inlet with an associated check valve. Stationary seals in the pump use the high pressures in the cylinder and the reservoir for producing the sealing forces necessary to prevent leakage. The primary piston seal consists of a long, controlled clearance gap which permits a small leakage but has only minor contact and thereby low sliding stresses and a long life.