A liquefied gas unloading and deep evacuation system may more quickly, more efficiently and more completely unload liquefied gases from transport tanks, such as rail cars, into stationary storage tanks or into truck tanks. The system may utilize a two stage compressor, an electric motor, a variable frequency drive, a four way valve, a three way valve, a two way valve, a programmable logic controller based control system and pressure and temperature transmitters. The valving enables deep evacuation of the transport or supply tank to more completely empty the transport tank. The programmable logic controller and variable speed drive may be used to variably control the speed of the two stage compressor so that the system may be running as fast as possible during changes in ambient temperature and/or different stages of offloading the liquefied gases without exceeding the compressor's horsepower limit.

The present application provides apparatus (15) for connection to an HVAC-R system during maintenance or commissioning. The apparatus includes a plurality of ports (16, 17, 18) for fluid connection to the HVAC-R system and to maintenance apparatus, for example a refrigerant tank, a refrigerant recovery unit and/or a vacuum pump. The apparatus also includes a plurality of fluid connections (20) between the plurality of ports, each of the plurality of fluid connections having an electrically actuatable valve (21) to open and close the fluid connection. The apparatus also includes a control unit configured to control each of the electrically actuatable valves to configure the plurality of fluid connections.

A pump assembly is disclosed comprising a pump body having a first pump stage housed in the pump body including a fluid inlet and a first and a second fluid outlet. A flow feed chamber is housed in the pump body in fluid communication with the second fluid outlet. A second pump stage housed in the pump body is in fluid communication with the flow feed chamber and includes at least one fluid outlet connected to the second pump stage. A valve assembly is operable into a first position to fluidically connect the fluid inlet through the first pump stage to the first fluid outlet. The valve assembly is further operable into a second position to fluidically connect the first pump stage to the second fluid outlet and the flow feed chamber and the flow feed chamber fluidically connected to the at least one fluid outlet through the second pump stage.

In a pump housing having an interior for accommodating a pump rotor, which may be transferred from a radially compressed state into a radially expanded state, and comprises a housing skin revolving in circumferential direction, as well as at least one reinforcement element, a stretch-resistant element revolving in circumferential direction is provided, which is stretched less than 5% in the expanded state as opposed to the force-free state in circumferential direction, and which limits any further expansion of the pump housing in radial direction.

A self-regulating fire pump unit which can be controlled to operate under required conditions for sourcing a fire protection system such as sprinklers. The fire pump unit can be operated in accordance with a control curve based on detected pressure and flow. The control curve can include: a) a first setpoint of rated total value of the system load for the pressure and the flow, b) a second setpoint of a minimum partial percentage of the rated total value of the pressure at an over-percentage of the rated total value of the flow, c) a path which maintains the rated total value of the pressure for all values of the flow up to the first setpoint, d) a path between the first setpoint and the second setpoint, e) a path from the second setpoint which limits values of the pressure for values of the flow greater than the second setpoint.

A device for protecting an electric pump against overpressures, which comprises a main body which forms a cavity with an axis of extension which is substantially parallel to an axis of extension of the main body and a flow control element which can slide in the cavity along the axis of extension of the cavity between a closed position, in which the flow control element affects an inlet of the cavity which can be connected fluidically to a delivery port of an electric pump, and an open position, in which the flow control element clears at least partially the inlet so as to place it in fluidic connection with an outlet of said cavity, elastic means designed to push the flow control element in response to the pressure that is present in the delivery port.

A method controls a circulation pump (1) in an installation with at least two circulation circuits (3, 4), with which the circulation pump (1) is integrated by way of a switch-over valve (2) into the one or the other circulation circuit (3 or 4) depending on the switched position. The pump (1) is activated differently depending on the switched position of the switch-over valve (2). The switch-over procedure is detected by way of determining the pressure course and/or the flow rate course in the pump (1) or an electrical variable which is dependent thereon, of the motor driving the pump, and the pump (1) is operated in another manner accordingly.

The present disclosure provides an engine cooling system for controlling the temperature of an engine of a motor vehicle. The system includes an engine cooling circuit for circulating a coolant to transfer heat from the engine to an airflow. An electric water pump is configured to circulate the coolant through the circuit at a maximum electric pump flow rate, and a mechanical water pump is configured to circulate the coolant through the circuit at a maximum mechanical pump flow rate that is higher than the maximum electric pump flow rate. The circuit further includes a selector valve configured to fluidly connect one of the electric water pump and the mechanical water pump to the engine. An engine control module generates a valve signal for actuating the selector valve to fluidly connect one of the electric water pump and the mechanical water pump to the engine.

A centrifugal pump assembly includes an electric drive motor (6, 8), a driven impeller (14) and a pump casing (2) which surrounds the impeller (14). A movable element (24; 24) is arranged a valve element. A section of the valve element is movable from a released position into a bearing position, fixed on a contact surface (60), by pressure which is produced by the impeller in the pump casing. A control device (64) moves the valve element from one switching position into another switching position and reduces the speed of the drive motor. Upon pressure in the pump casing dropping such that the valve element is no longer fixed on the contact surface and the valve element has been moved into the other switching position, the control device increases the speed of the drive motor again. A method for moving a valve element is provided.

A fluid compressor system configured to supply a compressed working fluid including at least a first air-end and a second air-end, a first and second intercooler, and a coolant circulation system having at least one throttle valve. The first and second intercoolers are configured to cool the compressed working fluid delivered by the first and second air-ends of the fluid compressor system, respectively. The coolant circulation system includes a coolant supplying header and a coolant collecting header, where the coolant supplying header supplies a coolant to the first intercooler and the second intercooler, and the coolant collecting header collects the coolant from the first intercooler and the second intercooler. The at least one throttle valve regulates a coolant flow discharged by one of the first intercooler or the second intercooler prior to entering the coolant collecting header.