Abstract: A liner retention system for a reciprocating pump having a piston and a piston rod operating in a cavity of a frame. The system includes a cylindrical liner for the piston and piston rod, the liner having a radially extending external shoulder. A liner clamp plate has a central opening receivable over the liner and a plurality of stud apertures. A plurality of studs extends from the frame, each stud terminating in a threaded end spaced from a module block. At least one compression sleeve has an inside diameter larger than an external diameter of the stud. Tensioner mechanism secures each stud to the liner clamp plate to thereby secure the cylindrical liner to the module block.

Abstract: An apparatus and method to assemble and disassemble a valve cover locking screw assembly for a reciprocating pump module block. The module block has a bore, a removable valve cover closing the bore, and a valve cover locking ring securable to the block and surrounding the bore with internal threads. A valve cover locking screw has cylindrical walls with external threads, a closed top, and an open bottom. A plurality of threaded bolts engage a plurality of threaded openings through the cylindrical walls of the locking screw so that the bolts force the valve cover against the module block thereby creating a fluid tight seal.