A method and a device for compensating leakage losses in a line system, in which at least one positive displacement pump and at least one shut-off member are provided, wherein the method and device can be used for the isobaric metering of liquid plastic components and wherein the actual liquid pressure in the system is determined by way of a pressure measuring device and, when the shut-off member is closed is regulated to a pressure target value by actuation of the positive displacement pump, wherein the conveying loss rate of the positive displacement pump, which ensues to maintain the pressure target value when the shut-off member is closed is added to a target delivery rate in order to compensate for the leakage loss occurring at the corresponding pressure target value.

A lubricating oil supply device for a vehicle includes an electric oil pump and an electronic control unit. The electronic control unit is configured to control the electric oil pump, determine whether or not lubricating oil needs to be supplied by the electric oil pump, control a drive duty of the electric oil pump to a first value when the ECU determines that lubricating oil needs to be supplied, and control the drive duty to a second value that is smaller than the first value when the ECU determines that lubricating oil does not need to be supplied. The electronic control unit is configured to perform duty variable control for controlling the drive duty to a third value, which is between the first value and the second value, during a predetermined changeover transition period, in changing over the drive duty from the first value to the second value.

Systems and methods for operating hydraulic fracturing units, each including a hydraulic fracturing pump to pump fracturing fluid into a wellhead and an internal combustion engine to drive the hydraulic fracturing pump, may include receiving signals indicative of operational parameters. The systems and methods also may include determining an amount of required fracturing power sufficient to perform the hydraulic fracturing operation, determining an available power to perform the hydraulic fracturing operation and a difference between the available power and the required power, and controlling operation of the hydraulic fracturing units based at least in part on the power difference. When the power difference is indicative of excess power available, the system and methods may include causing at least one of the hydraulic fracturing units to idle, and when the power difference is indicative of a power deficit, increasing a power output of at least one of the hydraulic fracturing units.

A method for determining a vacuum degree threshold is provided including: e acquiring the current altitude signal of a vehicle; when the current altitude signal is invalid, acquiring a vacuum degree threshold and a standard working time, which correspond to a historical altitude signal received by an electronic vacuum pump of the vehicle last time, the vacuum degree threshold includes a vacuum degree turn-on threshold value and a vacuum degree turn-off threshold; acquiring the actual working time of the vacuum degree threshold corresponding to the historical altitude signal of the electronic vacuum pump when the current working cycle is completed; and when the difference between the actual working time and the standard working time exceeds a preset range, updating, according to the difference, the vacuum degree threshold corresponding to the historical altitude signal, and taking the updated vacuum degree threshold as a target vacuum degree threshold of the next working cycle.

Systems and methods for operating hydraulic fracturing units, each including a hydraulic fracturing pump to pump fracturing fluid into a wellhead and an internal combustion engine to drive the hydraulic fracturing pump, may include receiving signals indicative of operational parameters. The systems and methods also may include determining an amount of required fracturing power sufficient to perform the hydraulic fracturing operation, determining an available power to perform the hydraulic fracturing operation and a difference between the available power and the required power, and controlling operation of the hydraulic fracturing units based at least in part on the power difference. When the power difference is indicative of excess power available, the system and methods may include causing at least one of the hydraulic fracturing units to idle, and when the power difference is indicative of a power deficit, increasing a power output of at least one of the hydraulic fracturing units.

A paint sprayer includes an end bell, a motor connected to the end bell, a pump drive connected to the end bell, a pair of protrusions attached to an extending from the end bell such that each protrusion is cantilevered from the end bell, and a pump assembly comprising a pair of mounting holes and containing a piston. The pair of mounting holes is adapted to receive and slide onto the pair of protrusions to mount the pump assembly on the end bell as well as slide off of the pair of protrusions to remove the pump assembly from the end bell. The pump drive is configured to covert rotational motion output by the motor to reciprocal motion. The pump assembly is configured to pump paint when reciprocated by the pump drive while mounted on the end bell.

There is provided an air pressure system for controlling an air compressor in real time in accordance with the actual usage of compressed air by a plurality of terminals. Furthermore, in case pressure losses change abruptly, unwanted electric power is prevented from being consumed by a stable operation free of response delays on the basis of a predicted model that assesses time lags of volume responses. There is provided an air pressure system for supplying compressed air discharged from an air compressor through an air tank and a piping system to a plurality of terminals that consume the compressed air, including a compressor pressure sensor for measuring the pressure of compressed air discharged from the air compressor, a plurality of terminal pressure sensors for measuring the pressures of compressed air supplied respectively to the terminals, a flow rate difference calculating device for calculating deviation information on the basis of a capacity of the air tank, information on the piping system, the pressure of compressed air discharged from the air compressor, and the pressures of compressed air supplied respectively to the terminals, and a control device for controlling operation of the air compressor on the basis of the deviation information.

A controller for a well system automatically profiles the system, detects a pre-charge of an associated pressurized storage tank, and automatically configures pressure-based control of a pump based on the detected pre-charge. The controller determines the pre-charge of the pressurized storage tank while the tank is connected to the system. While monitoring a system pressure, the controller activates the pump to initiate a filling operation of the pressurized storage tank. The controller analyzes a change in system pressure during the filling operation to determine the pre-charge of the pressurized storage tank. With the pre-charge determined, the controller automatically configures pressure settings for pressure-based control of the pump.

There is provided a wobble plate piston water pump for use in a pressure washer and driven by a driving source, the water pump includes a pump body, a wobble plate, four or more pistons and a water passage defined by a water inlet and a water outlet. The driving source being electric powered and having a power consumption of less than or equal to a 15 ampere draw at 120 volts or 220 volts or the driving source being gas powered and having an engine displacement of less than or equal to 250 cubic centimetres.

A system and method is provided for monitoring a hydraulic power system having at least one light emitter and a button. The method includes powering on the hydraulic power system, receiving an actuation at the button and detecting a release of the button after a first time interval, and entering a diagnostic state. The method further includes retrieving a code and displaying the code by turning on the emitter in a first pattern. In some embodiments, a system and method is provided for regulating a temperature of a hydraulic power system. In some embodiments, a system and method is provided for controlling operation of a hydraulic torque wrench.