An analysis method of absolute energy efficiency and relative energy efficiency of the compressed air system. For the compressed air system operating in a form of a single compressor, a gas flow rate and a corresponding operating power of the compressor operating in the single compressor model are measured under a specified flow rate. Meanwhile, influencing factors of the compressor operation are monitored. The absolute energy efficiency of the compressor is defined, and a curve of the absolute energy efficiency of the compressor varying with the operating time versus the above factors are plotted in a same coordinate system. Obtaining absolute energy efficiency data of the compressor in a corresponding state. By analyzing the absolute energy efficiency under corresponding conditions and based on the corresponding chart, the actual unit consumption of a given single compressor and its changing rule under different production and environmental operating conditions can be intuitively analyzed.

A nut of a helical gear of a piston pump of a hydraulic vehicle power brake system. The nut has a plastic body that is covered by a metal sleeve. The plastic body has a through hole having a nut thread.

A nut of a helical gear of a piston pump of a hydraulic vehicle power brake system. The nut has a plastic body that is covered by a metal sleeve. The plastic body has a through hole having a nut thread.

A subsea long-distance power-transmission system comprises an electrically driven pumping station for producing a flow of pressurised working fluid and an electricity generating station having an electrical generator coupled to a fluid-powered machine. A supply duct extends across the seabed between the pumping station and the generating station, that duct being arranged to convey the flow of working fluid from the pumping station to power the machine. Electric power is supplied to the pumping station from an electric power source, such as a national power grid, and is supplied from the generator to an electric power consumer far distant from the power source, such as a subsea oil and gas installation.

Provided is a safety valve (10) comprising a body (12) which defines an incoming fluid passage (14) and a return fluid passage (20). The incoming fluid passage (14) generally enables a fluid to pass from a fluid reservoir (18) through the body (12) to the tool head (16). The return fluid passage (20) generally enables a fluid to return from the tool head (16) through the body back to the fluid reservoir (18). The body (12) further comprises a diverter (22) which is displaceable between an active position and an inactive position. When the diverter (22) is in the active position, the diverter (22) redirects the fluid via a shunting passage (24) from the incoming fluid passage (14) to the return passage (20) to prevent operation of the tool head (16).

An electrically powered hydraulic fracturing system having pumps for pressurizing fracturing fluid, piping for carrying fracturing fluid, and vibration reducing equipment for use with the piping. The vibration reducing equipment includes helical coils that support the piping. The coils are made of a wire rope made of strands of steel cable twisted together. Grooved fittings are provided on some piping connections, and which allow pivoting between adjacent fluid conveyance members. Swivel joints are strategically located in the piping which allow rotational flexing between adjacent sections of the piping; thereby attenuating vibration in the piping but without stressing the piping.

An electrically powered hydraulic fracturing system having pumps for pressurizing fracturing fluid, piping for carrying fracturing fluid, and vibration reducing equipment for use with the piping. The vibration reducing equipment includes helical coils that support the piping. The coils are made of a wire rope made of strands of steel cable twisted together. Grooved fittings are provided on some piping connections, and which allow pivoting between adjacent fluid conveyance members. Swivel joints are strategically located in the piping which allow rotational flexing between adjacent sections of the piping; thereby attenuating vibration in the piping but without stressing the piping.

A hydraulic fracturing system includes a turbine generator for producing electricity at a well site, the turbine generator producing electrical energy at a voltage. The system also includes an electric pump electrically coupled to the turbine generator and receiving operative power from the turbine generator. The system further includes switch gear arranged between the electric pump and the turbine generator, the switch gear distributing electrical energy from the turbine generator to the electric pump, wherein the voltage remains substantially constant from the turbine generator to the electric pump.

A hydraulic fracturing system includes a turbine generator for producing electricity at a well site, the turbine generator producing electrical energy at a voltage. The system also includes an electric pump electrically coupled to the turbine generator and receiving operative power from the turbine generator. The system further includes switch gear arranged between the electric pump and the turbine generator, the switch gear distributing electrical energy from the turbine generator to the electric pump, wherein the voltage remains substantially constant from the turbine generator to the electric pump.

Embodiments relate to a hydraulic fracturing system that includes a blender unit. The system includes an auger and hopper assembly to receive proppant from a proppant source and feed the proppant to the blender unit for mixing with a fluid. A first power source is used to power the blender unit in order to mix the proppant with the fluid and prepare a fracturing slurry. A second power source independently powers the auger and hopper assembly in order to align the hopper of the auger and hopper assembly with a proppant feed from the proppant source. Thus, the auger and hopper assembly can be stowed or deployed without use of the first power source, which is the main power supply to the blender unit.