A linear compressor includes a discharge valve detachably attached to a front end surface of a cylinder to open and close a compression space of the cylinder; and a valve spring elastically supporting a rear surface of the discharge valve to press the discharge valve toward the front end surface of the cylinder. The discharge valve includes reinforced fiber, and the reinforced fiber is arranged parallel to the front end surface of the cylinder. Accordingly, while a rigidity of the discharge valve is improved, a weight of the valve is reduced to enhance responsiveness of the valve, suppress abrasion of the cylinder, and reduce striking sound.

A fluid-working machine has a plurality of working chambers, e.g., cylinders, of cyclically changing volume, a high-pressure fluid manifold and a low-pressure fluid manifold, at least one valve linking each working chamber to each manifold, and electronic sequencing means for operating said valves in timed relationship with the changing volume of each chamber, wherein the electronic sequencing means is arranged to operate the valves of each chamber in one of an idling mode, a partial mode in which only part of the usable volume of the chamber is used, and a full mode in which all of the usable volume of the chamber is used, and the electronic sequencing means is arranged to select the mode of each chamber on successive cycles so as to infinitely vary the time averaged effective flow rate of fluid through the machine.

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 linear compressor includes a cylinder, a piston, and a discharge valve, wherein the piston includes a first part extending in the axial direction, a second part having a diameter greater than that of the first part and formed at one end of the first part facing the discharge valve, and a third part having a diameter greater than that of the first part and formed at the other end of the first part. The second part includes a first outer circumferential surface extending backward from a front surface of the piston, and a second outer circumferential surface spaced apart from the first outer circumferential surface in a direction away from the discharge valve, and a distance between the first outer circumferential surface and an inner circumferential surface of the cylinder is less than a distance between the second outer circumferential surface and the inner circumferential surface of the cylinder.

An automatic bidirectional valve includes: a valve body, a central conduit that crosses the valve body and is provided with a first opening in a first end of the valve body and a second opening made in an opposite second end thereof, and a peripheral conduit made in the valve body, provided with a first opening, made in a portion of the valve body between the first and second ends, and a second opening made in the second end. A first shutter is movable between a closing position and an opening position, a first elastic element configured to generate a force adapted to maintain the first shutter in the closing position, a second shutter movable between a closing position, and an opening position, a second elastic element configured to generate a force to maintain the second shutter in the closing position, and a retaining body fixed to the valve body.

A system and process for predicting the failure of a machine begins with the step of loading a slope signature library into the control system, in which the slope signature library correlates time-to-failure based on rates of change of one or more measured conditions. The process includes the steps of activating the machine, determining baseline measurements, and detecting an out-of-spec measurement. Once an out-of-spec measurement is made, the process includes the determination of the rate of change for the out-of-spec measurement. A slope signature is calculated based on the rate of change for the measured condition, which is compared against the slope signature library to determine a predicted time-to-failure based on the calculated slope signature, and outputting the predicted time-to-failure. The process can be used to modify the operation of the machine to extend the predicted time-to-failure.

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 thermal monitoring system includes: one or more thermal sensors configured to monitor the temperature of one or more portions of a fracking pump and generate one or more thermal indication signals; a processing system configured to receive the one or more thermal indication signals and associate the one or more thermal indication signals with one or more operating temperatures of the one or more portions of the fracking pump; and an indication system configured to provide a thermal condition indicator based, at least in part, upon the one or more operating temperatures of the one or more portions of the fracking pump.

A linear compressor includes a discharge valve detachably attached to a front end surface of a cylinder to open and close a compression space of the cylinder; and a valve spring elastically supporting a rear surface of the discharge valve to press the discharge valve toward the front end surface of the cylinder. The discharge valve includes reinforced fiber, and the reinforced fiber is arranged parallel to the front end surface of the cylinder. Accordingly, while a rigidity of the discharge valve is improved, a weight of the valve is reduced to enhance responsiveness of the valve, suppress abrasion of the cylinder, and reduce striking sound.

An automatic bidirectional valve includes: a valve body, a central conduit that crosses the valve body and is provided with a first opening in a first end of the valve body and a second opening made in an opposite second end thereof, and a peripheral conduit made in the valve body, provided with a first opening, made in a portion of the valve body between the first and second ends, and a second opening made in the second end. A first shutter is movable between a closing position and an opening position, a first elastic element configured to generate a force adapted to maintain the first shutter in the closing position, a second shutter movable between a closing position, and an opening position, a second elastic element configured to generate a force to maintain the second shutter in the closing position, and a retaining body fixed to the valve body.