A pump, which generally includes a pump housing and a pump piston. The pump housing defines a central longitudinal bore, a transverse bore communicating with the central bore for conveying a liquid through the pump housing, a liquid reservoir communicating with the central bore and the transverse bore for retaining an amount of the liquid conveyed through the transverse bore and a pressure relief slot extending from the transverse bore to the liquid reservoir. The pump piston is axially and rotatably slidable within the central longitudinal bore for pumping the liquid through the transverse bore.

A long sleeve cartridge for being inserted into a fluid end block of a pump is disclosed. The long sleeve cartridge includes a body and a sleeve bore extending through the body. The sleeve bore includes a first inner diameter and a second inner diameter. The first inner diameter is less than the second inner diameter. A first aperture is located on the body, and a second aperture is located on the body in a radial position substantially diametrically opposite of the first aperture. A packing seal assembly is secured within the long sleeve cartridge. The packing seal assembly includes one or more seals and a biasing mechanism to provide a compression force on the seals. The packing seal assembly is arranged within the second inner diameter when the packing seal assembly is disposed within the long sleeve cartridge.

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.

Provided is a linear compressor including a linear motor having a mover reciprocating with respect to a stator; a piston coupled to the mover to reciprocate; a cylinder into which the piston is slidingly inserted, the cylinder having an inner circumferential surface forming a bearing surface together with an external circumferential surface of the piston, the cylinder forming a compression space together with the piston, and the cylinder having at least one first hole formed through the inner circumferential surface of the cylinder and an outer circumferential surface of the cylinder to guide refrigerant discharged from the compression space to the bearing surface; and a porous member inserted into the outer circumferential surface of the cylinder and configured to cover the first hole, the porous member having multiple micropores smaller than the first hole.

Fluid end for high pressure reciprocating pump, in particular for hydraulic fracturing pumps, comprising: a body having a first bore (18) for receiving a reciprocating plunger (31), a second bore (19) for accommodating a suction valve (41), and a third bore (21) for accommodating a discharge valve (43), the second bore (19) and the third bore (21) being perpendicular to the first bore (18); at least a tubular sleeve (30) in said first bore (18); at least a tubular cartridge (30) in the second bore and/or third bore; and a fluid tight seal between contacting surfaces of said sleeve (30) and said cartridge (30).

A plunger pump includes a cylinder section having a cylinder chamber and a spacer section sliding against a portion of the plunger closer to a proximal end side than a portion of a plunger advancing and retracting into the cylinder chamber. The cylinder section is made of a material having first hardness, and the spacer section being made of a resin material having second hardness softer than the first hardness. A length in an axial direction from a proximal end of a sliding portion of the spacer section sliding against the plunger to a distal end of the spacer section is larger than a maximum stroke length of reciprocation of the plunger.

A method of remanufacturing a fluid end block of a well stimulation pump includes cleaning an interior surface of a body of the fluid end block. The interior surface defines a chamber, a plunger passage in communication with the chamber, an intake passage in fluid communication with the chamber, and a discharge passage in fluid communication with the chamber. The interior surface is made from a base material. The interior surface of the fluid end block is cold-worked to produce a compressive residual stress layer within the body. A coating layer made from a non-metallic material is applied to at least a portion of the interior surface of the body. The non-metallic material is different from the base material.

A nitriding layer (13) is formed on the front surface side of a base material of a cylinder block (7) including an opening side end surface (7B) and each cylinder hole (12). Then, a piston sliding surface (12A) of each cylinder hole (12) is formed as a compound layer-removed hole (17) by removing a compound layer (16) that is located on the front surface side of the nitriding layer (13) by using polishing means such as, for example, honing and so forth. Further, a compound layer-removed surface (18) is formed on a part (A) where a compound layer-removed hole (17) and a cylinder inlet side tapered surface (12B) of each cylinder hole (12) intersect by using the polishing means such as, for example, the honing and so forth. This compound layer-removed surface (18) is formed as a tapered-state inclined surface of an angle α.

In certain examples, a printing system comprises: a depositing system to deposit printing fluid on a print medium; a reservoir; and a displacement pump to move printing fluid to the depositing system from the reservoir. The displacement pump comprises: a pump body defining a chamber, an inlet to fluidly connect the chamber to the reservoir, and an outlet to fluidly connect the chamber to the depositing system; and a displacement member movable relative to the pump body; the displacement member having an outer surface and comprising a cavity located in a portion of the outer surface disposed in the chamber. In use, the displacement member is movable to close the inlet and to force printing fluid in the chamber through the outlet to the depositing system.

A method of manufacturing a plunger pump includes a temperature difference generation process of generating a difference in temperature with respect to a normal temperature state for either one of an outer cylinder or an inner cylinder, a cylinder insertion process of inserting the inner cylinder inside the outer cylinder in a state in which the inner cylinder has a smaller outer diameter than an inner diameter of the outer cylinder as a result of the temperature difference generated by the temperature difference generation process, an elimination process of eliminating the generated temperature difference, and a plunger placement process of placing a circular tube-shaped plunger in a pressure chamber of the inner cylinder so as to enable of reciprocating motion by the plunger.