A system for monitoring a piece of hydraulic fracturing equipment such as a positive displacement pump. The system includes a plurality of sensors configured to detect conditions of the hydraulic fracturing pump and a processor that is communicatively coupled to the plurality of sensors and configured to analyze data received from the plurality of sensors. The processor is also configured to predict faults in the hydraulic fracturing pump based on the data analysis. The system also includes a communication interface that is configured for transmitting predicted fault data to one or more devices.

Wearable fluid delivery devices and pump systems having a pump status determination assembly to determine a status of at least one component of a fluid pump are described. For example, in one embodiment, a fluid pump system for a wearable fluid delivery device may include a control system, a first pump element associated with a first electrical element, a second pump element associated with a second electrical element, wherein the first pump element is configured to engage the second pump element to form an electrical circuit between the first electrical element and the second electrical element, the control system configured to receive at least one signal from the electrical circuit. Other embodiments are described.

A monitoring system may include a strain gauge, a position sensor, and a torque sensor. The strain gauge may measure strain in a chamber of the pressure pump and generate a strain signal representing the strain measurement. The position sensor may measure a position of a rotating member and generate a position signal representing the position measurement. The torque sensor may measure torque in a component of the pressure pump and generate a torque signal representing the torque measurement. The torque measurement may be used with the strain measurement and the position measurement to determine a condition of the pressure pump.

Various embodiments of the present disclosure are directed to reciprocating compressors. In one example embodiment, a reciprocating compressor is disclosed including a cylinder, a piston, at least one suction valve, at least one pressure valve, at least one connection chamber, a sequence valve, a sequence valve control unit, and an unloader. The piston moves back and forth in the cylinder in order to form a compression chamber in the cylinder. The at least one suction valve and the at least one pressure valve are provided on the compression chamber. The at least one connection chamber having a connection chamber volume, which is connected to the compression chamber via at least one overflow opening. The sequence valve opens and closes the at least one overflow opening, and the sequence valve control unit controls the sequence valve. The unloader is actuated by an electrically controllable actuator.

An electronic pressure compensated hydraulic motor pump is controlled to provide variable output power based on a variable input signal. The variable output power feature allows the motor pump to be used with a power management system to better match the output power of the motor pump with the available power of an electrical system. The ability to provide variable output power provides beneficial power management for electrical systems that switch between different power modes, e.g., between a generator power mode and a battery power mode.

A system may include multiple strain gauges and multiple position sensors positioned on multiple pressure pumps. The strain gauges may measure strain in chambers of the pressure pumps. The position sensors may measure positions of rotating members of the pressure pumps. One or more computing devices may be communicatively couplable to the strain gauges and the position sensors to determine an adjustment to a flow rate of fluid through at least one pump using a strain measurement and a position measurement for the at least one pump such that a timing of changes in composition of the fluid delivered to into a first manifold at an input for the pressure pumps matches the timing of the changes in composition of the fluid delivered from a second manifold at an output for the pressure pumps.

Apparatus and methods for measuring backlash of a gear train of a pump unit for pumping a fluid. An example method may include locking a crankshaft of the pump unit such that the crankshaft cannot rotate. The method may further include commencing operation of a processing device to receive rotational position measurements indicative of rotational position of an output shaft of a prime mover, cause the prime mover to rotate the output shaft in a first direction until the output shaft reaches a first rotational position, and cause the prime mover to rotate the output shaft in a second direction until the output shaft reaches a second rotational position. The processing device may then determine backlash of the gear train by determining rotational distance between the first rotational position of the output shaft and the second rotational position of the output shaft.

An electronically commutated hydraulic machine is coupled to a drivetrain. Working chambers of the hydraulic machine are connected to low and high pressure manifold through electronically controlled valves. The phase of opening and closing of the valves has a default. In order to avoid cycle failure due to acceleration events, for example due to backlash in the drivetrain, the phase of opening or closing of the electronically controlled valves is temporarily advanced or retarded from the default timing.

An ocular drainage system is provided for treating diseases that produce elevated intraocular pressures, such as glaucoma, wherein the system includes an implantable device and an external control unit, the implantable device includes a non-invasively adjustable valve featuring at least one deformable tube and a disk rotatably mounted within a housing, such that rotation of the disk using the external control unit causes the disk to apply a selected amount of compression to the deformable tube, thereby adjusting the fluidic resistance of the deformable tube and regulating the intraocular pressure.

A control device for a fuel injection system includes a CPU which generates a drive signal for instructing execution of compression by a feel pump; a fuel pump drive circuit which controls application of electric power to a solenoid of the feel pump based on the drive signal; a boost circuit provided with a capacitor for storing electric power to be used for driving an injector; a charging circuit which leads a current generated when the application of electric power to the solenoid is stopped to the capacitor; and an excess electric power consumption circuit which consumes excess electric power of the capacitor. While feel injection from the injector is stopped, the CPU counts the number of times the feel pump is driven and turns off the drive signal so as to stop driving the feel pump as soon as the drive count has exceeded a predetermined count value.