A positive displacement reciprocating multi-cylinder pump has a pair of cams and associated bearings and yokes that cooperatively and positively reciprocate the pistons. The fluid flow paths are configured through specially designed intake and outlet manifolds to provide intrinsic cooling of the bearings through specially configured fluid flow paths at distal ends of the pump. An intentional head geometry that is identical for each piston may be readily machined using exterior bores. Each head defines a cylinder, captures both inlet and outlet one-way valves, and provides essential fluid flow paths about the cylinders. All bearings are of the sealed type, and no additional oil baths or the like are required, permitting the pump to be stored, transported, and used in any orientation.

A discharge valve of a high-pressure pump is placed in a discharge passage and is openable to enable flow of fuel from a pressurizing chamber to a discharge outlet in response to a fuel pressure difference between the pressurizing chamber side and the discharge outlet side. A relief is placed in a relief passage. The relief passage communicates between a branching portion, which is located on a side of the discharge valve where the discharge outlet is placed in the discharge passage, and a return portion, which merges with a damper chamber. The relief valve is openable to enable flow of the fuel from the branching portion to the return portion in response to a fuel pressure difference between the branching portion side and the return portion side. A discharge passage orifice is placed between the discharge valve and the branching portion in the discharge passage and constricts a flow passage cross-sectional area of the discharge passage.

A valve arrangement for a high pressure pump includes a pump housing with a depression, and a valve housing configured to be inserted in the depression, and a clamping disc. The valve housing has at least one radial projection with a first axial boundary surface and a second axial boundary surface arranged opposite the first axial boundary surface, wherein the clamping disc extends radially over the radial projection of the valve housing and has a third axial boundary surface that corresponds with the second axial boundary surface of the valve housing. On the circumferential side, the clamping disc has a thread that can be screwed into a thread on the inner side of the depression to brace the valve housing onto the first boundary surface.

Provided is a high-pressure fuel pump that ensures oil tightness even at high fuel pressure and has a small and lightweight inexpensive discharge valve structure. Therefore, a high-pressure fuel pump according to the present invention includes: a discharge valve arranged on a discharge side of a pressurizing chamber; a discharge valve seat on which the discharge valve is seated; and a facing member configured independently as a separate member from the discharge valve seat and located on an opposite side of the discharge valve seat with the discharge valve interposed therebetween, in which a stroke direction regulating portion that regulates displacement of the discharge valve in a stroke direction is formed on a tapered surface of the facing member.

Provided is a high-pressure fuel pump that ensures oil tightness even at high fuel pressure and has a small and lightweight inexpensive discharge valve structure. Therefore, a high-pressure fuel pump according to the present invention includes: a discharge valve arranged on a discharge side of a pressurizing chamber; a discharge valve seat on which the discharge valve is seated; and a facing member configured independently as a separate member from the discharge valve seat and located on an opposite side of the discharge valve seat with the discharge valve interposed therebetween, in which a stroke direction regulating portion that regulates displacement of the discharge valve in a stroke direction is formed on a tapered surface of the facing member.

A method is used to produce a piston pump having a housing and a piston subassembly. The piston subassembly is displaceably guided in the housing and has a first, rod-like piston element and a second, sleeve-like piston element. The second piston element is connected to the first piston element via a press fit. At least one transverse bore and a longitudinal bore are arranged in the second piston element. A stop edge for the housing is arranged on the second piston element. The piston subassembly also has an inlet valve, which includes a receiving element, in which an inlet valve spring and an inlet valve sealing element are arranged. The piston subassembly also has a corresponding inlet valve seat, which is arranged on the second piston element. While the second piston element is being machined, the press fit and the longitudinal bore are produced and/or finished in one step.

A fluid end assembly of a hydraulic fluid pump includes a housing having a first housing bore and a second housing bore offset axially from the first housing bore. A plate is fastened to the housing. The plate has a first plate bore axially aligned with the first housing bore and a second plate bore axially aligned with the second housing bore. A first removable valve cover closes the first housing bore and a second removable valve cover closes the second housing bore. A first retainer engages the first plate bore and abuts the first removable valve cover and a second retainer engages the second plate bore and abuts the second removable valve cover.

A fluid end assembly of a hydraulic fluid pump includes a housing having a first housing bore and a second housing bore offset axially from the first housing bore. A plate is fastened to the housing. The plate has a first plate bore axially aligned with the first housing bore and a second plate bore axially aligned with the second housing bore. A first removable valve cover closes the first housing bore and a second removable valve cover closes the second housing bore. A first retainer engages the first plate bore and abuts the first removable valve cover and a second retainer engages the second plate bore and abuts the second removable valve cover.

A power end assembly includes a crankshaft section, a crosshead section, and a connector section coupled together by one, two, or more sets of stay rods. The power end may include one or more support plates that are coupled to the crankshaft section and/or crosshead section. The crosshead section includes a plurality of individual crosshead frames. The connector section may include a plurality of individual connector plates or may be a unitary connector plate. The power end is configured to be coupled to a fluid end assembly by coupling the fluid end assembly to the connector plates.

A power end assembly includes a crankshaft section, a crosshead section, and a connector section coupled together by one, two, or more sets of stay rods. The power end may include one or more support plates that are coupled to the crankshaft section and/or crosshead section. The crosshead section includes a plurality of individual crosshead frames. The connector section may include a plurality of individual connector plates or may be a unitary connector plate. The power end is configured to be coupled to a fluid end assembly by coupling the fluid end assembly to the connector plates.