A fluid pump has a housing, a chamber having an inlet and an outlet, an inlet valve, an outlet valve, and a plunger. The plunger has a plunger tube extending into the chamber and supported for movement, on a suction stroke, to introduce a fluid into the chamber via the inlet, and, on a discharge stroke, to displace the fluid from the chamber via the outlet. An electromagnetic driving unit moves the plunger in two opposite directions. A magnetic core is located adjacent the plunger for establishing a magnetic path across the electromagnetic driving unit and the plunger. The core is located in the path of movement of the plunger on the suction stroke, and is protected or covered by a material against contact with the fluid in the housing.

The piston compressor comprises a cylinder as well as a piston arranged therein, a carrier housing with a crosshead mounted in the carrier housing, a spacer which connects the cylinder to the carrier housing, as well as a piston rod extending in a longitudinal direction (L) which connects the crosshead to the piston, wherein the spacer comprises a plurality of support arms, wherein the support arms are connected to and support the cylinder.

A reciprocating compressor 1A includes a compression part 2 compressing, by a piston 6, gas sucked into a cylinder 4 through a suction valve 36, and discharging the compressed gas through a discharge valve 51, a piston drive part 3 supplying a force to the piston 6 to reciprocate the piston 6 via a piston rod 9 coupled to the piston 6, and a housing 17 accommodating the compression part 2 and forming a vacuum region around the compression part 2.

A mud pump with components manufactured from high strength and toughness steel is disclosed. The mud pump includes a power end and a fluid end. The power end includes a motor, crankshaft rotationally engaged with the motor and a connecting rod rotationally engaged with the crank shaft. The fluid end includes a piston, a cylinder, a drilling fluid module, a discharge manifold, and a strainer cross. At least one of the plunger, the drilling fluid module, the discharge manifold, and the strainer cross has the following composition in weight percent: 0.25-0.55% carbon, 0.70-1.50% manganese, a maximum of 0.025% phosphorous, a maximum of 0.050% sulfur, a maximum of 0.80% silicon, 0.10-0.80% nickel, 1.40-2.20% chromium, 0.10-0.55% molybdenum, a maximum of 0.030% vanadium, a maximum of 0.35% copper, a maximum of 0.040% aluminum, a balance of iron, and incidental impurities.

An oscillating positive displacement pump with at least one mobile part arranged to be movable relative to a fixed part. The mobile part is driven and drives a displacement element of the positive displacement pump. An electrodynamic drive is provided as a drive, on which a plurality of coils and permanent magnets are provided that are arranged on the mobile part of the drive respectively, and at least one guide member is provided on the drive, which allows the mobile part to move only along a degree of translation freedom. The positive displacement pump is designed as a diaphragm pump, which is associated with a measurement and control unit with a data storage and data processor, which processes a position signal of the mobile part and the strength of the drive current as a measured and/or control variable. An arrangement of a plurality of such positive displacement pumps and a method of operating at least one such oscillating positive displacement pump are also provided.

A mud pump with components manufactured from high strength and toughness steel is disclosed. The mud pump includes a power end and a fluid end. The power end includes a motor, crankshaft rotationally engaged with the motor and a connecting rod rotationally engaged with the crank shaft. The fluid end inclues a piston, a cylinder, a drilling fluid module, a discharge manifold, and a strainer cross. At least one of the plunger, the drilling fluid module, the discharge manifold, and the strainer cross has the following composition in weight percent: 0.25 - 0.55% carbon, 0.70 -1.50% manganese, a maximum of 0.025% phosphorous, a maximum of 0.050% sulfur, a maximum of 0.80% silicon, 0.10 - 0.80% nickel, 1.40 - 2.20% chromium, 0.10 - 0.55% molybdenum, a maximum of 0.030% vanadium, a maximum of 0.35% copper, a maximum of 0.040% aluminum, a balance of iron, and incidental impurities.

A piston includes a piston cap and a piston rod with the piston cap being removable from the piston rod body. The piston cap includes a cap body and a socket extending into the cap body. A mounting portion of the piston rod body extends into the socket of the cap body to connect the piston rod body to the piston cap. A wear sleeve is mounted on the piston rod.

This disclosure presents a pump body, such as a fluid end housing used in a reciprocating pump, which provides an integral seating or engagement surface (or a valve seat integrated with the pump body) for a valve member. The integral engagement surface removes the need for a separate, replaceable valve seat and can last as long as the service life of the fluid end housing. This saves multiple maintenance services during the service life of the fluid end housing, along with the associated down time, labor costs, and material costs for the new valve seats. The integral engagement surface thus performs as an integral valve seat to the pump body. In some embodiments, the integral engagement surface may be coated, heat-treated, or otherwise modified to increase its wear resistance, such as by including one or more wear-resistant inserts to at least partially contact the valve member.

An ultra-long stroke multi-cylinder reciprocating pump comprises a small gear, a large gear, a crankshaft, connecting rods, fixed racks, a frame, translation pinions, movable racks, clamps, piston rods, cylinder sleeves, pistons, suction valves, liquid discharging valves, guide rails, a prime motor, a coupling, and a small gear shaft. When the prime motor rotates, the small gear is meshed with the large gear to drive the crankshaft to rotate, an axial center of the translation pinion is driven by the connecting rod to move reciprocally, the translation pinion is meshed with the fixed rack and the movable rack simultaneously, and a distance of reciprocating motion of the movable rack is twice a distance of reciprocating motion of a rotation center of the translation pinion, so that an ultra-long stroke is realized.

A cover, a fluid end and a plunger pump are provided. The cover includes: a body, the body being cylindrical, and the body including a first end, a second end, and a side surface connecting the first end and the second end; a main flow channel extending along an axis of the body; a plurality of subsidiary flow channels, each of the plurality of subsidiary flow channels being communicated with the main flow channel; a first opening, located at the first end and communicated with the main flow channel; and a plurality of second openings, located at the side surface of the body; each of the plurality of subsidiary flow channels being communicated with at least one of the plurality of second openings.