A system and method that remotely monitors and controls proppant usage in a fracturing operation. The system and method allow operators to wirelessly monitor and control proppant storage units from inside a datavan through sensors and control mechanisms that interface with fracturing software to schedule the flow of the proppant. A sensor monitors the weight, container level, or volume of the proppant being used to keep the induced hydraulic fracture open. A serial to Ethernet converter converts this information and sends it wirelessly to a datavan. A user at the datavan controls the proppant usage through a display in the datavan of the storage units with the appropriate weight. The container monitoring software links with the fracturing software, providing real-time information about proppant usage so that the user can properly schedule proppant flow to the well through valves, conveyor belts, and other control mechanisms.

A system and method that remotely monitors and controls proppant usage in a fracturing operation. The system and method allow operators to wirelessly monitor and control proppant storage units from inside a datavan through sensors and control mechanisms that interface with fracturing software to schedule the flow of the proppant. A sensor monitors the weight, container level, or volume of the proppant being used to keep the induced hydraulic fracture open. A serial to Ethernet converter converts this information and sends it wirelessly to a datavan. A user at the datavan controls the proppant usage through a display in the datavan of the storage units with the appropriate weight. The container monitoring software links with the fracturing software, providing real-time information about proppant usage so that the user can properly schedule proppant flow to the well through valves, conveyor belts, and other control mechanisms.

A digital positioner for a valve includes a valve controller configured to obtain a set point value for a valve travel of a valve, and generate a pulse-width modulated current signal based on the set point value. The digital positioner also includes a current-to-pressure converter configured to receive the pulse-width modulated current signal from the valve controller, convert the pulse-width modulated current signal to a pulse-width modulated pressure signal, and provide the pulse-width modulated pressure signal to a pneumatic actuator in the valve to adjust a position of the valve.

A prime mover and a plurality of hydraulic actuators, a hydraulic machine having a rotatable shaft in driven engagement with the prime mover and comprising working chambers, a hydraulic circuit between working chambers of the hydraulic machine and the hydraulic actuators, each working chamber of the hydraulic machine comprising a low-pressure and high-pressure valves regulating the flow of hydraulic fluid between the working chamber and a corresponding low-pressure manifold and a high-pressure manifold. The hydraulic machine being configured to actively control the low-pressure valves of the working chambers to select the net displacement of hydraulic fluid by each working chamber on each cycle of working chamber volume, and thereby the net displacement of hydraulic fluid by the working chambers, responsive to a demand signal, wherein the apparatus further comprises a controller configured to calculate the demand signal in response to a measured property of the hydraulic circuit or actuators.

The subject matter of this specification can be embodied in, among other things, a controller apparatus that includes a digital controller configured to provide a digital position signal based on a setpoint and a differential analog feedback signal, and a converter circuit configured to provide a differential analog electrohydraulic servo valve position control signal based on the digital position signal, and provide the differential analog feedback signal based on the differential analog electrohydraulic servo valve position control signal.

The subject matter of this specification can be embodied in, among other things, a controller apparatus that includes a digital controller configured to provide a digital position signal based on a setpoint and a differential analog feedback signal, and a converter circuit configured to provide a differential analog electrohydraulic servo valve position control signal based on the digital position signal, and provide the differential analog feedback signal based on the differential analog electrohydraulic servo valve position control signal.

Many operators choose not to utilise partial-stroke testing arrangements even when the equipment required for it to be performed is available, due to a perceived risk of over-travel and/or spurious trip. To alleviate this, we describe a safety valve system comprising a valve operable to move between an operating state and a safe state, a valve actuator operatively connected to the valve to control its state, and including a bias toward the safe state, a pair of drive members powered by a pressure media, each acting against the bias to urge the valve toward the operating state, a first control valve arranged to selectively convey pressure media to both drive members and to withdraw supply on receipt of a safety trigger, and a second control valve arranged to selectively convey pressure media to one drive member only of the pair and to withdraw supply on receipt of a test signal. In this way, a partial stroke test is possible via the second control valve, but the other drive member of the pair will remain active thus acting as a buffer that prevents excessive movement of the valve.

A digital positioner for a valve includes a valve controller configured to obtain a set point value for a valve travel of a valve, and generate a pulse-width modulated current signal based on the set point value. The digital positioner also includes a current-to-pressure converter configured to receive the pulse-width modulated current signal from the valve controller, convert the pulse-width modulated current signal to a pulse-width modulated pressure signal, and provide the pulse-width modulated pressure signal to a pneumatic actuator in the valve to adjust a position of the valve.

A system for mounting an annular component on a shaft, comprising (a) a hydraulic nut having an annular coaxial cavity and a ring-like piston, displaceable within the cavity; (b) a displacement sensor for providing a displacement signal indicating the axial displacement of the piston within the cavity; (c) a wireless displacement transmitter for transmitting the displacement signal; (d) a pressure sensor for providing a pressure signal indicating a pressure within the cavity; (e) a wireless pressure transmitter for transmitting the pressure signal; (f) a pump arranged to pump fluid into the cavity; and (g) a remote control device having a communications device arranged to receive transmitted pressure and displacement signals, wherein the remote control device is arranged to output control information for controlling the pump.

The disclosure relates to a method for operating a hydraulic drive which comprises a hydraulic consumer with a positionable piston in a cylinder which is connected to a tank at one connection via a pump of variable rotational speed and at another connection via a proportional valve, wherein a position of the piston is controlled using a model-based control in which a rotational speed of the pump is used as a manipulated variable and in which a position of the proportional valve is preset.