A valve is provided. The valve includes a body provided with fluid passages for circulating fluid therein. The body has a body interface with ports connected to the fluid passages. The valve also includes a valve element having a valve element interface facing the body interface. The valve element can move between different positions so as to permit or obstruct communication between the fluid passages. A biasing element biases the valve element interface against the body interface. A load varying mechanism is provided to load the biasing element with different sealing load forces according to the different positions of the valve element. The sealing load force applied on the rotor is thus decreased during rotation, reducing friction between the valve body and the valve element.

A valve assembly, includes a valve body having an inlet portion, an outlet portion, and a constriction portion; a shaft positioned within the valve body and extending along a longitudinal axis of the valve body; a cone provided within the inlet portion and configured to move along the shaft; a spring configured to bias the cone away from the constriction and positioned between a first piston fixed to the cone and a second piston fixed to the shaft; and an adjustable spacer positioned between a fixed position on the shaft and the second piston. The adjustable spacer is adjustable in length to change an effective length of the adjustable spacer and change a position of the second piston on the shaft.

Apparatus and method contemplating a high pressure fluid end assembly having a body defining a body bore and defining a recess in the body intersecting the body bore. A closure is joined to the body and forms a sealing surface. A seal is mounted to the body in the recess and configured to extend from the recess beyond the body bore to seal against the sealing surface formed by the closure.

A fluid end assembly comprising a housing having multiple conduits formed therein. A tubular sleeve is installed within one of the conduits and is configured to house a plurality of packing seals. A seal is installed within a groove formed in the walls of the housing surrounding the tubular sleeve such that the seal engages an outer surface of the tubular sleeve.

Apparatus and method contemplating a high pressure fluid end assembly having a body defining a body bore and defining a recess in the body intersecting the body bore. A closure is joined to the body and forms a sealing surface. A seal is mounted to the body in the recess and configured to extend from the recess beyond the body bore to seal against the sealing surface formed by the closure.

A valve assembly, includes a valve body having an inlet portion, an outlet portion, and a constriction portion; a shaft positioned within the valve body and extending along a longitudinal axis of the valve body; a cone provided within the inlet portion and configured to move along the shaft; a spring configured to bias the cone away from the constriction and positioned between a first piston fixed to the cone and a second piston fixed to the shaft; and an adjustable spacer positioned between a fixed position on the shaft and the second piston. The adjustable spacer is adjustable in length to change an effective length of the adjustable spacer and change a position of the second piston on the shaft.

A fluid end assembly comprising a housing having multiple conduits formed therein. A tubular sleeve is installed within one of the conduits and is configured to house a plurality of packing seals. A seal is installed within a groove formed in the walls of the housing surrounding the tubular sleeve such that the seal engages an outer surface of the tubular sleeve.

A quick disconnect fitting includes a plug and a socket to receive the plug. The plug includes a fluid channel, an inlet to the fluid channel, and a pressure regulating valve assembly. The valve can include a poppet, and a valve nozzle comprising an orifice. The valve assembly resides in the fluid channel. The socket includes a socket stem to contact the valve assembly and push the valve assembly into the fluid channel of the plug upon the socket receiving the plug.

Apparatus and method contemplating a high pressure fluid end assembly having a body defining a body bore and defining a recess in the body intersecting the body bore. A closure is joined to the body and forms a sealing surface. A seal is mounted to the body in the recess and configured to extend from the recess beyond the body bore to seal against the sealing surface formed by the closure.

A fluid end assembly comprising a housing having multiple conduits formed therein. A tubular sleeve is installed within one of the conduits and is configured to house a plurality of packing seals. A seal is installed within a groove formed in the walls of the housing surrounding the tubular sleeve such that the seal engages an outer surface of the tubular sleeve.