Abstract: A pressure containment apparatus includes a shell having a top end and a bottom end forming a pressure chamber. The pressure containment apparatus also includes a liner having an outside diameter larger than an inside diameter of the shell, wherein the liner is removably restrained within the shell by a frictional force between the liner and the shell. A retainer and retainer spring supporting the retainer are disposed within a space between the liner and a bottom manifold such that the retainer and retainer spring minimize axial forces exerted on a bottom end flange of the pressure containment apparatus.

Abstract: An improved cylinder for pumps of the type where a plunger moves within a cylinder forcing fluid through a port in a cap fitted into one end of the cylinder. A multiple diameter cap encircled by a multiple diameter sleeve transmits the pressure force acting on the largest surface area of the cap through the sleeve to a smaller area acting on the packing seal. Since the pressure multiplied by the area is a constant, a higher pressure is applied to a smaller area at the seals; and with a higher pressure acting on the seals than existing in the working fluid, a seal is created to prevent passage of the fluid.

Abstract: A free piston compressor for gases and liquids in which the positive pressure of the incoming fluid holds the piston against the piston rod during the intake stroke. In a specific form, the cylinder head is a plug of larger diameter than the piston which can be unscrewed to permit removal and replacement of the piston for service.

Abstract: The valve of U.S. Pat. No. 3,774,877 in which have valve operating pistons are mounted in a tubular sleeve received in a bore in a two part valve body, one part containing the connection for P1 and the other part containing the connection for P2 and the valve port.