Patent ID: 11859643
Assignee: SPM OIL & GAS INC.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 15:
16. A fluid end for a reciprocating pump system, comprising:
a fluid end block defining a fluid chamber;
a plunger reciprocally disposed in the fluid chamber to generate fluid pressure therewithin;
an outlet fluid passage formed in the fluid end block in fluid communication with the fluid chamber, the outlet fluid passage including an outlet valve;
an inlet fluid passage formed in the fluid end block in fluid communication with the fluid chamber, the inlet fluid passage including an inlet valve; and
a retainer nut assembly including:
a fastener comprising a generally cylindrical configuration, first and second ends, external threads configured to engage corresponding threads of the fluid end block, and a cavity formed at the first end;
a suction cap configured to sealingly fit to the fluid end block, the suction cap including a first portion configured to engage an internal shoulder of a counterbore of the fluid end block and a second portion configured to be disposed in a reduced-diameter portion of the counterbore;
a load piston movably disposed in the cavity and adjacent the suction cap, wherein the load piston is substantially a solid disk with a radius that is greater than a radius of the second portion of the suction cap;
a bore formed in the fastener in communication with the cavity and provided with a hydraulic fluid;
a pressure piston movably disposed in the bore, wherein movement of the pressure piston, in the bore, is parallel to movement of the load piston in the cavity;
a threaded passageway formed in the fastener in communication with the bore and open to the second end; and
a locking bolt disposed in the threaded passageway, the locking bolt, when inserted into the threaded passageway, configured to contact the pressure piston and generate fluid pressure on the load piston with the hydraulic fluid, wherein movement of the locking bolt, in the threaded passageway, is parallel to movement of the pressure piston and the load piston.