A valve device includes a body that defines a passage through which a fluid flows, a shaft that is movably supported with respect to the body and defines an axis, a valve element that is fixed to the shaft to open and close the passage; and a cylindrical bearing bush that movably supports the shaft with respect to the body, in which the bearing bush includes a mixed region in which a metal core material and expanded graphite are mixed with each other, and a first expanded graphite region made of only the expanded graphite such that the metal core material is not exposed in an inner circumferential side region in contact with an outer circumferential surface of the shaft.

Disclosed is a status monitoring and fault diagnosis system for a plunger pump, including a monitoring and fault diagnosis device. The monitoring and fault diagnosis device monitors and diagnoses a hydraulic end assembly of a plunger pump. The monitoring and fault diagnosis device further monitors and diagnoses a power end assembly and/or a reduction gearbox assembly. Beneficial effects: The diagnosis system monitors and diagnoses not only a hydraulic end assembly, but also a power end assembly and/or a reduction gearbox assembly, that is, an equipment fault can be accurately predetermined in time for an entire plunger pump, so that high-pressure, large-displacement, and continuous operation requirements on fracturing sites at present are better satisfied, and on-demand maintenance is adopted instead of regular examination and maintenance, thereby saving labor, time, and materials to achieve economic efficiency.

A monitoring system for reciprocating pump having a plunger connected to a crankshaft by a crosshead and connecting rod assembly. The monitoring system includes a plurality of wireless temperature sensors which each have a temperature probe connected to a sensor head, a plurality of antennas which each have an antenna head configured to communicate wirelessly with a corresponding one of the sensor heads, and a signal processing unit connected to the plurality of antennas. Each temperature probe is positioned in contact with a corresponding crank pin bearing, wrist pin bearing or crosshead bearing. Each sensor head is mounted to the crosshead, and each antenna head is mounted to the pump at a location in which communication is enabled between the antenna head and its corresponding sensor head when the crosshead reaches a first position during each reciprocation of the crosshead. In operation, each antenna head transmits a radar pulse which is reflected by its corresponding sensor head, the reflected pulse is received by the antenna head and communicated to the signal processing unit, and the signal processing unit determines the temperature of the sensor head from the reflected pulse, which temperature is indicative of the temperature of its corresponding monitored bearing.

A pump monitoring system may include a sensor for monitoring a parameter of a pump system. The sensor may include at least one of an ammeter in electrical communication with an electric motor driving a pump and a torque sensor on a drive shaft that drives a pump. The system may also include a controller in data communication with the sensor to receive sensor data. The controller may be configured to assess the performance of the respective pump in one or more ways. At least one of the one or more ways may include reliance on the sensor data from only one sensor to identify valve or seat wear or failure. Alternatively or additionally, at least one of the one or more ways may identify valve or seat wear or failure without reliance on pump output pressure.

Disclosed is a status monitoring and fault diagnosis system for a plunger pump, including a monitoring and fault diagnosis device. The monitoring and fault diagnosis device monitors and diagnoses a hydraulic end assembly of a plunger pump. The monitoring and fault diagnosis device further monitors and diagnoses a power end assembly and/or a reduction gearbox assembly. Beneficial effects: The diagnosis system monitors and diagnoses not only a hydraulic end assembly, but also a power end assembly and/or a reduction gearbox assembly, that is, an equipment fault can be accurately predetermined in time for an entire plunger pump, so that high-pressure, large-displacement, and continuous operation requirements on fracturing sites at present are better satisfied, and on-demand maintenance is adopted instead of regular examination and maintenance, thereby saving labor, time, and materials to achieve economic efficiency.

A monitoring system can include a position sensor coupled to a pump to sense a position of a rotating assembly member of the pump and generate an associated position signal. The position signal can be used to determine a position of a displacement member in a chamber in a fluid end of the pump. The monitoring system can include a strain gauge to measure strain in the chamber and generate an associated strain signal. The strain signal can be used to determine an actuation point for a valve in the chamber. A computing device can determine an actuation delay of the valve by correlating the position of the displacement member in the chamber with the actuation point for the valve. The actuation delay can represent the actuation point relative to the position of the displacement member during operation of the pump.

A fluid end is formed from a first body attached to a separate second body. Each body includes an external surface. When the bodies are attached, their respective external surfaces are in flush engagement. A plurality of bores are formed in the second body that are alignable with a plurality of corresponding bores formed in the first body. The fluid end may be used with seals disposed within recesses within each bore to seal against corresponding sealing surfaces. Further, retaining closures may be bolted to the fluid end bodies, such that the closures have a threadless connection to the fluid end bodies. Various combinations of such components may be utilized.

A monitoring system may include a position sensor, a strain gauge, and a computing device for determining the condition of a valve in a chamber of a pump using strain measurements. The strain gauge may determine strain in the chamber. The position sensor may determine the position of a crankshaft coupled to a plunger in the chamber. The computing device may receive signals generated by the strain gauge and the position sensor related to the strain in the chamber and the position of the crankshaft, respectively, and may process the signals to determine delays in the actuation of the valves.

A valve assembly includes a valve body, a seal, and a supplemental material. The valve assembly configured to reduce the effects of wear and erosion of the seal and valve body by including material with increased hardness. The supplemental material has a higher hardness level than the valve body and is inserted on the contact surface of the valve body. The seal can include a plurality of materials, each having different hardness levels. The location of the supplemental material can vary and the overall radial distribution on the contact surface may vary.

A fluid end is formed from a first body attached to a separate second body. Each body includes an external surface. When the bodies are attached, their respective external surfaces are in flush engagement. A plurality of bores are formed in the second body that are alignable with a plurality of corresponding bores formed in the first body. The fluid end may be used with seals disposed within recesses within each bore to seal against corresponding sealing surfaces. Further, retaining closures may be bolted to the fluid end bodies, such that the closures have a threadless connection to the fluid end bodies. Various combinations of such components may be utilized.