Modular reciprocating pump rod column system, rod column assembly, plunger rod column assembly, and methods of use

A hydraulically actuated extension rod, comprising:

• a hydraulic system;
• an extension rod assembly;
• the extension rod assembly extending a length from a first end to a second end;
• the extension rod assembly having an exterior surface;
• the extension rod assembly having a plurality of attachment features of the first end;
• the extension rod assembly having a plurality of attachment features of the second end;
• the extension rod assembly having a flange;
• an end cap assembly;
• the end cap assembly having a lock nut;
• the end cap assembly having an end cap;
• the end cap assembly having a hydraulic port;
• the end cap assembly having a hydraulic cross port;
• the end cap assembly having a center shaft;
• the center shaft operably connected to a piston;
• the end cap assembly having a plurality of disc springs;
• a subrod assembly;
• the subrod assembly extending a length from a first end to a second end;
• the subrod assembly having an inner shaft;
• a piston rod assembly;
• the piston rod assembly extending a length from a first end to a second end;
• the piston rod assembly having a lock nut;
• wherein the plurality of disc springs can be engaged and disengaged for replacement of parts and ease of maintenance;
• wherein engaging the plurality of disc springs creates an axial force on the center shaft of the end cap assembly;
• wherein disengaging the plurality of disc springs releases the axial force on the center shaft of the assembly.

A method of assembling a reciprocating pump rod column for replacement of fluid end expendables, comprising the steps:

• rotating the reciprocating pump rod column so that an extension rod assembly is at its rear most position;
• actuating an extension rod assembly end cap assembly, wherein actuating the extension rod assembly end cap assembly is causing compression of internal springs, in turn causing a center shaft to extend outward from a face of the end cap assembly;
• installing a piston rod onto the extension rod;
• wherein installing the piston rod assembly onto the extension rod assembly is piloting the center shaft of the extension rod assembly into a counterbore on a back of the piston rod;
• aligning a set of cross-pin holes of the piston rod with a second set of cross-pin holes of the center shaft of the extension rod;
• wherein aligning the set of cross-pin holes of the piston rod with the second set of cross-pin holes of the center shaft of the extension rod assembly is completed by utilizing a keyway;
• installing a first pin;
• wherein the first pin fastens the piston rod assembly to the extension rod;
• wherein installing the first pin is placing the first pin into a first pin bore;
• actuating the end cap assembly;
• wherein actuating the end cap assembly removes compression of an internal spring pack;
• wherein removing compression of the internal spring pack extends an overall space of the spring pack;
• wherein extending the spring pack shifts the center shaft inwards;
• wherein inwards is toward the extension rod;
• wherein actuating the end cap assembly causes a high force;
• wherein the high force causes a rear face of the piston rod to press against the end cap assembly;
• rotating the reciprocating pump such that the installed piston rod moves forward until the piston is engaged into a liner.