A fracturing apparatus is provided. The fracturing apparatus includes: a plunger pump including a hydraulic end and a power end, the power end having a power end oil outlet and at least one power end oil inlet that are coupled to each other; and a power end lubricating system, including: a lubricating oil tank configured for defining an accommodation space, at least one lubrication pump having a lubrication pump oil inlet and a lubrication pump oil outlet that are coupled to each other, and at least one lubrication motor configured for providing power for the at least one lubrication pump, wherein at least a portion of at least one of the lubrication motor and the lubrication pump is located in the accommodation space.

A fluid flow meter comprising a fluid pump to displace fluid with pumping strokes of one or more pumping stroke types wherein each of the one or more stroke types displaces a known volume of fluid, a sensor functionally associated with a fluid reservoir and adapted to generate a signal indicative of a fluid pumping condition within the fluid reservoir, which fluid reservoir is integral or functionally associated with the pump, and circuitry to trigger one or a sequence of strokes of the pump in response to a signal from the sensor.

Disclosed are a method, device and system for a fluid flow meter. According to some embodiments of the present invention, a fluid flow meter that has a fluid pump to displace fluid with one or more pumping strokes of one or more pumping stroke types wherein each of the stroke types displaces a known volume of fluid from a fluid reservoir. A sensor functionally associated with the fluid reservoir and adapted to generate a signal indicative of a fluid pumping condition within the fluid reservoir, and circuitry to trigger one or a sequence of strokes of the pump in response to a signal from the sensor that the triggering condition within the fluid reservoir has been met.

A fracturing apparatus includes: a plunger pump having a hydraulic end and a power end, wherein the power end comprises a power end oil outlet and at least one power end oil inlet that are coupled to each other; a power end lubricating system, including a lubricating oil tank defining an accommodation space, at least one lubrication pump having a lubrication pump oil inlet and a lubrication pump oil outlet that are coupled to each other, and at least one lubrication motor configured to provide power for the at least one lubrication pump; a temperature detector disposed on any one of the oil return pipeline, the power end oil outlet, and the lubricating oil tank; and a control system connected to the temperature detector and the power end lubricating system and configured to control the power end lubricating system.

A fracturing apparatus includes: a plunger pump having a hydraulic end and a power end, wherein the power end comprises a power end oil outlet and at least one power end oil inlet that are coupled to each other; a power end lubricating system, including a lubricating oil tank defining an accommodation space, at least one lubrication pump having a lubrication pump oil inlet and a lubrication pump oil outlet that are coupled to each other, and at least one lubrication motor configured to provide power for the at least one lubrication pump; a temperature detector disposed on any one of the oil return pipeline, the power end oil outlet, and the lubricating oil tank; and a control system connected to the temperature detector and the power end lubricating system and configured to control the power end lubricating system.

A thick matter pump includes a hydraulically-driven two-cylinder piston-pump configured to generate a thick matter delivery pressure. The thick matter pump also includes a hydraulic pump configured to apply hydraulic fluid to the two-cylinder piston-pump via a drive line. The hydraulic pump includes a pressure regulator that is adjustable to a target value of pressure of the hydraulic fluid for limiting the thick matter delivery pressure, and the thick matter delivery pressure is adjustably limited. The pressure of the hydraulic fluid is limited in the drive line, via an adjustable pressure-limiting valve, to an adjustable maximum pressure. The target pressure of the pressure regulator and the maximum pressure of the hydraulic fluid are adjustable through a joint adjusting element.

A thick matter pump includes a hydraulically-driven two-cylinder piston-pump configured to generate a thick matter delivery pressure. The thick matter pump also includes a hydraulic pump configured to apply hydraulic fluid to the two-cylinder piston-pump via a drive line. The hydraulic pump includes a pressure regulator that is adjustable to a target value of pressure of the hydraulic fluid for limiting the thick matter delivery pressure, and the thick matter delivery pressure is adjustably limited. The pressure of the hydraulic fluid is limited in the drive line, via an adjustable pressure-limiting valve, to an adjustable maximum pressure. The target pressure of the pressure regulator and the maximum pressure of the hydraulic fluid are adjustable through a joint adjusting element.

Hydraulic axial piston unit having a rotational group for driving or being driven by a driving shaft, and a tiltable displacement element for adjusting the displacement volume of the rotational group. The rotational group includes a rotatable cylinder block in which working pistons are mounted reciprocally moveable in cylinder bores for conveying hydraulic fluid from a kidney-shaped inlet port to a kidney-shaped outlet port on a valve segment. At least two control ports are located on the valve segment each between the respective circumferential ends of the kidney-shaped inlet port and the outlet port. The control ports can be brought sequentially in fluid connection with the cylinder bores when the cylinder block is rotating. At least one hydraulic fluid injector is connected fluidly to one control port, for sequentially injecting pressurized hydraulic fluid via the control port into the passing cylinder bores. Via the other control port hydraulic fluid can be drained from passing cylinder bores.

Provided is a variable displacement pump which sucks and discharges a working fluid by moving a piston with a stroke in response to an inclination angle of a swash plate, the variable displacement pump including: a control piston which includes a columnar piston portion pressing the swash plate and adjusts the inclination angle of the swash plate between a maximal inclination angle in which a discharge capacity of the working fluid becomes maximal and a minimal inclination angle in which the discharge capacity of the working fluid becomes minimal; a piston accommodation portion which is formed in the housing and accommodates the piston portion; and a pressed portion which is disposed between the swash plate and the piston portion and is pressed toward the swash plate by the piston portion, in which when the inclination angle of the swash plate is an intermediate inclination angle in which the discharge capacity of the working fluid becomes an intermediate amount between the maximal amount and the minimal amount, a contact point between the piston portion and the pressed portion is located at a center portion including an axis center of the piston portion in an end surface on the side of the swash plate in the piston portion.

Provided is a variable displacement pump which sucks and discharges a working fluid by moving a piston with a stroke in response to an inclination angle of a swash plate, the variable displacement pump including: a control piston which includes a columnar piston portion pressing the swash plate and adjusts the inclination angle of the swash plate between a maximal inclination angle in which a discharge capacity of the working fluid becomes maximal and a minimal inclination angle in which the discharge capacity of the working fluid becomes minimal; a piston accommodation portion which is formed in the housing and accommodates the piston portion; and a pressed portion which is disposed between the swash plate and the piston portion and is pressed toward the swash plate by the piston portion, in which when the inclination angle of the swash plate is an intermediate inclination angle in which the discharge capacity of the working fluid becomes an intermediate amount between the maximal amount and the minimal amount, a contact point between the piston portion and the pressed portion is located at a center portion including an axis center of the piston portion in an end surface on the side of the swash plate in the piston portion.