A fluid end assembly comprising a plurality of fluid end sections positioned in a side-by-side relationship. Each fluid end section comprises a housing having a bore formed therein for housing a reciprocating plunger. Fluid is prevented from leaking around the plunger by a packing seal assembly. The packing seal assembly comprises one and only one packing seal.

Various assemblies that can be used in a mud pump with a plunger-style piston to reduce seal failures, to offer control in variability of the circumference of the piston to thereby control fluid pressure, and to provide visibility into seal condition during operation. In one embodiment, a sleeve that can vary the overall effective circumference of the piston enables fluid pressure control. In some embodiments, seal failure within a pump can be monitored via a drain port that would receive drilling fluid leaking past a seal during operation of the pump. A discharge valve can be provided between an inlet and an outlet of the mud pump to reduce the load on pump components during start-up. Additional systems, devices, and methods are also disclosed.

A compressor and method for compressing a working medium, including moving a drive piston which is driven by way of a driving medium within a first cylinder between a first end position and a second end position; moving a high pressure piston which compresses the working medium within a second cylinder between a first end position and a second end position; arranging a high pressure seal for sealing the high pressure piston; arranging a magazine having a receptacle for the high pressure seal and at least one replacement high pressure seal in a first operating position, in which the high pressure piston is sealed by way of the high pressure seal; and transferring the magazine from the first operating position to a second operating position, in which the high pressure piston is sealed by way of the replacement high pressure seal.

A high-pressure fuel pump includes a pump housing which defines a pumping chamber, a fuel inlet which allows low-pressure fuel into the pumping chamber, a fuel outlet which allows high-pressure fuel out of the pumping chamber, and a plunger bore which extends along an axis and opens into the pumping chamber. The high-pressure fuel pump also includes a pumping plunger which reciprocates within the plunger bore along the axis such that reciprocation of the pumping plunger within the plunger bore increase and decreases a volume of the pumping chamber. The pumping plunger includes a sealing ring groove which is concentric with the plunger bore, the sealing ring groove including a sealing ring therein which engages the plunger bore in an interference fit. A diametric clearance greater than 12 microns is provided between the pumping plunger and the plunger bore.

A high-pressure fuel pump includes a pump housing, a pump piston accommodated in a receiving opening of the pump housing, a high-pressure seal which surrounds the pump piston in a sealing manner and which seals off a high-pressure region from a low-pressure region, and a guide device which comprises at least two guide portions that are axially spaced apart from one another and guide the pump piston with a sliding fit. The at least two guide portions are arranged in the receiving opening of the pump housing. A first guide portion is arranged, as seen in an axial direction, on a side of the high-pressure seal facing toward the delivery space. And a second guide portion is arranged, as seen in the axial direction, on a side of the high-pressure seal facing away from the delivery space.

A hydraulic end assembly structure of a plunger pump, comprising a valve housing assembly, a suction gland and a suction pressing cap. The suction gland is connected to the suction pressing cap, and the suction gland is connected to the valve housing assembly through the suction packing seal assembly.

A pump system includes a housing, a lubricant system, and control circuitry. The housing includes a pump chamber defined by the housing and a throat seal. The lubricant system includes a lubricant pump, a lubricant gallery defined within the housing of the main pump, and a lubricant circuit fluidly connecting the lubricant pump and the lubricant gallery. The throat seal is disposed adjacent to and between the pump chamber and the lubricant gallery. The control circuitry is configured to cause the lubricant pump to pump a purge volume of lubricant through the lubricant system, cause the lubricant pump to stop pumping for a first time period after the lubricant pump has pumped the purge volume, and cause the lubricant pump to pump the purge volume of lubricant through the lubricant system after the first time period.

A power piston in a power cylinder borehole of a hydraulic block of a hydraulic power unit of a hydraulic power vehicle braking system is only guided radially in an axially delimited guide section. The power cylinder borehole is configured with a larger diameter axially outside the guide section. A brake fluid channel extends through the guide section up to an opening of a brake fluid line.

A well service pump system for supplying working fluid to a well, the pump system having structural joint coupled to and extending between the housing of a hydraulic ram cylinder and the housing of a working fluid end cylinder that maintains the distance between the housings and stabilizes the housings relative to one another without interfering with the operation of the pump system. The structural joint further permits the use of minimal supporting structures for securing the hydraulic ram cylinder and working fluid end cylinder to a surface, such as the bed of a trailer.

A well service pump system for supplying working fluid to a well, the pump system having structural joint coupled to and extending between the housing of a hydraulic ram cylinder and the housing of a working fluid end cylinder that maintains the distance between the housings and stabilizes the housings relative to one another without interfering with the operation of the pump system. The structural joint further permits the use of minimal supporting structures for securing the hydraulic ram cylinder and working fluid end cylinder to a surface, such as the bed of a trailer.