Abstract: Plunger pump fluid ends incorporate housings with structural features that facilitate manufacture while providing improved internal access, reduced weight, and reduced likelihood of fatigue failures compared to conventional fluid end housings. Certain fluid ends incorporate frangible pressure relief means in suction valves for protection from overpressure-induced catastrophic failure. Oblong bore transition areas, when present, and barrel-profile central cavities provide obtuse bore intersection angles and effectively reduce fluid end weight while reducing peak cyclic fluid end housing stress by redistributing stress within the fluid end housing.

Abstract: A fluid end assembly comprising a housing, valve bodies, seals, seats, springs, and other associated parts, paired with a suction manifold that facilitates bi-directional fluid flow. The suction manifold of this invention is designed to preserve fluid energy that will ensure complete filling of the cylinder in extreme pumping conditions. The suction manifold utilizes a chamber design positioned immediately below the suction valves, eliminating all connecting ducts. Alternate embodiments of this invention include a suction manifold with an integral fluid dampeners or stabilizers.

Abstract: A positive displacement pump fluid end with multiple fluid chambers and each fluid chamber comprising a valve body, valve seal, seat, spring, and external guide. External top male stem guide is integral to the fluid end discharge cover or the suction valve spring retainer. Female guide is internal and integral with the valve body. When the valve opens hydrodynamic forces and moments align the valve to prevent rotation. An embodiment features tapered male and female guide members to further assist in correct alignment of the valve with the seat. Various additional embodiments assist in venting any trapped fluids between the male and female portions of the guide.

Abstract: A tungsten carbide seat for high-pressure oilfield well service pumps is disclosed. A bonding agent, in conjunction with an interference tapered fit between the valve seat and fluid end housing eliminates stresses created in prior art interference fits. Three interface embodiments are disclosed: a shallow taper combined with a shoulder, a steep taper without a shoulder, and a compound surface in which the seat has an external concave surface and the housing surface that mates with the seat has a convex surface.

Abstract: A cylinder heater useful in fabricating sleeves for high pressure pump liners comprises a support rotatably supporting a hollow circular cylinder having a metallic powder layer contacting a portion of its inner surface. A vibration sensor indicates vibration of the cylinder, and at least one temperature sensor indicates at least one temperature of the cylinder. At least one circumferential induction heating coil around the cylinder is positionable via the support along the longitudinal axis of cylinder rotation. Longitudinal position and power output of at least one heating coil, and cylinder rotational speed, are adjusted by a controller communicating with the support, the vibration sensor, at least one temperature sensor, and at least one heating coil. Controlled heating of the cylinder and the metallic powder layer results in a stratified abrasion-resistant fused metallic layer on the cylinder's inner surface. The fused layer may be honed to make a liner sleeve.

Abstract: A high pressure piston for use within a liner sleeve of a reciprocating pump comprises a dual-durometer elastomeric seal having first and second coaxial seal sections and, in certain embodiments, a circumferential bearing ring. Interactions of the seal components, including seal elastomers, result in stress redistribution within the seal which maintains sealing preload, with corresponding improved extrusion resistance and seal durability. When a bearing ring is present, a pump's pressure stroke causes at least a portion of the bearing ring to elastically expand radially to narrow or close the extrusion gap, thus tending to block elastomer extrusion by establishing sliding contact between the bearing ring's external surface and the liner. On the pump's return stroke the slightly wider extrusion gap allows cooling water directed generally toward the proximal flange of the piston hub to better cleanse, as well as cool, the liner wall.

Abstract: Differential coefficients of thermal expansion facilitate close approximation during cooling of a sintered cemented carbide tubular inlay preform (e.g., a first tubular portion) which is vacuum brazed within a corresponding tubular metal hull (e.g., a second tubular portion). Such a tubular inlay preform comprises at least one metal carbide and at least one nonvolatile cement which have previously been compressed and sintered in a predetermined shape. The tubular inlay preform's modulus of elasticity and thermal conductivity substantially exceed the corresponding parameters of the tubular metal hull, whereas the hull's coefficient of thermal expansion exceeds that of the preform. Longitudinal movement of a tubular inlay preform within a tubular hull may be limited by structural features of the hull and/or preform. Additionally, circumferential compression of a tubular inlay preform due to hoop stress in a corresponding tubular metal hull increases as the hull cools after vacuum brazing.

Abstract: Tapered valve guide and spring retainer assemblies are described for use in plunger pump housings that incorporate corresponding outwardly flared discharge and suction bores, as well as structural features for stress-relief. Plunger pumps so constructed are relatively resistant to fatigue failure because of stress reductions, and they may incorporate a variety of valve styles, including top and lower stem-guided valves and crow-foot-guided valves, in easily-maintained configurations. Besides forming a part of valve guide and spring retainer assemblies, side spacers may be shaped and dimensioned to improve volumetric efficiency of the pumps in which they are used.

Abstract: A valve body and seal assembly comprises a valve body symmetrical about a longitudinal axis and comprising a circumferential seal retention groove and a frusto-conical valve body impact area for contacting a valve seat. An elastomeric seal is cast-in-place in the circumferential seal retention groove. Each seal comprises first and second seal sections in contact via an intra-seal interface, the interface simultaneously extending radially outward and longitudinally. First seal sections may comprise a first polyurethane having a higher modulus than a second polyurethane of which second seal sections may be comprised. First seal sections are cast and partially cured in a mold which is rotating about the longitudinal axis. Second seal sections are cast after the first seal sections are partially cured, resulting in the intra-seal interface shape described above. Cross-linking between first and second seal sections across the intra-seal interface is thus facilitated.

Abstract: Hot-isostatic-pressure (HIP) is used to bond a cemented carbide inlay (e.g., an inlay ring) on a metal substrate (e.g., a hull ring). For example, an inlay ring is made from a powdered metal inlay preform typically comprising at least one metal carbide and at least one nonvolatile cement. The inlay preform is compressed and sintered to make an inlay ring having a predetermined shape, the inlay ring having a modulus of elasticity substantially greater than that of a hull ring. An inlay ring and a hull ring are sealingly vacuum brazed together with at least one evacuated bonding area between them. HIP is applied to compress the hull ring against the inlay ring, thus fusing the hull ring and inlay ring in at least one evacuated bonding area. Following HIP, the inlay ring and hull ring form a fused assembly in which the inlay ring substantially retains its predetermined shape.

Abstract: A valve body substantially symmetrical about a longitudinal axis has at least one internal space and comprises guide means and two separately formed portions joined by at least one cylindrical web. One or more passages spaced apart from the longitudinal axis allow fluid communication between at least one internal space and space external to the valve body. At least one internal space may be substantially filled with a substantially incompressible flowable substance to facilitate pressure equalization across the valve body. Forging or casting valve body portions to near-net-shape prior to joining minimizes machining necessary to achieve a final desired shape. Increased valve durability and reduced metal wear arise from reduced valve body weight and correspondingly reduced impact loading as the valve body moves to seal against a valve seat. Valve sealing may be aided by an elastomeric seal in a peripheral integral seal retention groove of the valve body.

Abstract: A valve body and seal assembly comprises a valve body having one or more circumferential seal retention grooves and a dual-durometer elastomeric seal cast-in-place in at least one groove. Each seal comprises first and second sections in contact along a substantially non-planar intra-seal interface. First seal sections typically comprise polyurethane having a higher modulus than the polyurethane typically comprising second seal sections. Residual elastomer shrinkage stress present after curing of a cast-in-place dual-durometer elastomeric seal is redistributed within the seal sections to maintain beneficial preload. Seal configurations described herein are also associated with decreased shear-related elastomer fatigue and extrusion damage associated with repeated valve seat impact. Valve service life is increased by beneficial preload maintained by the synergistic interaction of first and second seal sections.

Abstract: Hot-isostatic-pressure (HIP) is used to make substantially nonporous cemented carbide inlays on metal substrates. A radiused shell preform typically comprising at least one metal carbide and at least one nonvolatile cement is shaped as a rigid frusto-conical shell having a substantially uniform thickness and a predetermined radius on every edge. HIP pressure is applied via a conforming adjustable sliding element to compress the preform against a conforming substrate. Surfaces of the conforming adjustable sliding element and conforming substrate, and/or the radiused shell preform, may in certain embodiments be coated substantially uniformly with at least one nonvolatile cement. Space around a radiused shell preform is evacuated without the need to totally enclose the radiused shell preform and its substrate in a can. Certain embodiments provide for leak testing of welded seals prior to application of HIP, and other embodiments make the use of welded seals unnecessary.

Abstract: A valve body and seal assembly comprising a valve body having one or more peripheral integral seal retention grooves and one or more peripheral single-durometer and/or dual-durometer elastomeric seals, each seal being cast-in-place in an integral seal retention groove having adhesion-inhibiting surfaces and offset circular serrations of predetermined height on opposing groove walls. Adhesion-inhibiting surfaces reduce or eliminate internal elastomer stress due to curing of cast-in-place elastomeric seals. Serrations on each of the opposing groove walls are offset to accommodate differing stress concentrations in the walls. Opposing groove walls diverge peripherally. Offset serrations result in decreased metal fatigue from impact and bending stress. Offset serrations also improve valve sealing and increase valve service life by maintaining correct seal position on the valve body while minimizing background stress in the seal elastomer(s).

Abstract: Tapered valve guide and spring retainer assemblies are described for use in plunger pump housings that incorporate corresponding outwardly flared discharge and suction bores, as well as structural features for stress-relief. Plunger pumps so constructed are relatively resistant to fatigue failure because of stress reductions, and they may incorporate a variety of valve styles, including top and lower stem-guided valves and crow-foot-guided valves, in easily-maintained configurations. Besides forming a part of valve guide and spring retainer assemblies, side spacers may be shaped and dimensioned to improve volumetric efficiency of the pumps in which they are used.

Abstract: A valve body having at least one internal hollow or space comprises two separately formed portions joined by at least one cylindrical web. Internal space may communicate with space outside the valve body via a fluid passage, and internal space may be filled with a substantially incompressible flowable substance to facilitate pressure equalization across the valve body. Forging or casting valve body portions to near-net-shape prior to joining minimizes machining necessary to achieve a final desired shape. Increased valve durability and reduced metal wear arise from the reduced valve body weight and correspondingly reduced impact loading as the valve body moves to seal against a valve seat. A single-durometer or dual-durometer elastomeric seal may be cast and cured in place in a peripheral integral seal retention groove, coupled thereto in part through welding flash protruding into the groove and/or through at least one serration in the groove.

Abstract: Suction valve spring retainers mounted using an access bore plug are described for use in plunger pump housings having an offset access bore and incorporating structural features for stress-relief. These pump housing structural features accommodate access bore plugs that secure suction valve spring retainers that are internally located substantially centrally over the suction bore transition area of the plunger pump housing. Access bore plugs are secured in place on the pump housing using one or more threaded retainers. Plunger pumps so constructed are relatively resistant to fatigue failure because of stress-reducing structural features, and they may incorporate a variety of valve styles, including top and lower stem-guided valves and crow-foot-guided valves, in easily-maintained configurations. Suction valve spring retainers mounted in plunger pump housings may also incorporate a suction valve top stem guide.

Abstract: A high pressure piston for use within a liner for a reciprocating pump comprises an elastomeric seal and an annular bearing ring. During the pump's pressure stroke at least a portion of the bearing ring elastically expands radially to narrow or close the extrusion gap, thus tending to block elastomer extrusion and establish sliding contact between the bearing ring's outer surface and the liner. An extrusion control groove located radially inward from the peripheral bearing ring contact surface of certain embodiments also tends to block elastomer extrusion. Under reduced pressure on the pump's return stroke, the bearing ring elastically contracts radially, slightly widening the extrusion gap. On the pump's return stroke the slightly wider extrusion gap allows cooling water directed generally toward the proximal flange of the piston hub to better cleanse, as well as cool, the liner wall.

Abstract: A valve body and seal assembly comprising a top-stem-guided valve body having at least one cast-in-place elastomeric seal insert in a peripheral seal retention groove and a cast-in-place top guide stem sleeve is made by pouring and curing liquid elastomer in at least one mold comprising the peripheral seal retention groove and the top guide stem. Mold surfaces contacting the poured elastomer are adhesion-inhibiting surfaces which reduce or eliminate background elastomer stress due to shrinkage during curing of the elastomer, and which allow limited relative movement of cast-in-place elastomer with respect to the valve body. Serrations on each of the opposing walls of the seal retention groove are offset to moderate differing stress concentrations in the groove walls.

Abstract: Methods and apparatus are disclosed for making substantially nonporous powdered metal (P/M) inlays on substrates using hot-isostatic-pressure (HIP). Methods described herein differ from conventional practice in their use of new apparatus for steps including: formation and maintenance of a P/M preform through use of an adjustable sliding element; application of increased pressure to a P/M preform via the adjustable sliding element; and evacuation of space around a P/M preform without the need to totally enclose a P/M preform and its substrate in a can. Certain embodiments provide for leak testing of welded seals prior to HIP, and other embodiments make the use of welded seals unnecessary.