To eliminate accumulation of air while preventing a decrease in pump efficiency, a pump is provided. The pump includes a rotary shaft, an impeller that is attached to the rotary shaft and that rotates with rotation of the rotary shaft, a casing that surrounds the rotary shaft, a shaft sealing device that seals a gap between the casing and the rotary shaft, and a baffle plate part that is located between the impeller and the shaft sealing device and attached to a rotating body. The baffle plate part extends in a direction that is inclined or orthogonal with respect to a surface orthogonal to an axial direction of the rotary shaft.

An impeller includes a housing having a fluid inlet cavity defining a rotational axis. A plurality of vane are inlets arranged along an inner surface of the fluid inlet cavity and a plurality of vane outlets are circumferentially arranged along a rim of the housing. Each of the vane outlets is fluidly connected to a corresponding vane inlet by a corresponding internal channel situated internal to the housing. Each of the channels maintains a triangular cross-section from the vane inlet to the vane outlet.

A pump includes a shaft that is rotatable about a central axis. An inducer is mounted on the shaft and has an inducer blade and inducer shroud attached at an outer end of the inducer blade. An impeller is mounted on the shaft downstream of the inducer and has an impeller blade and an impeller shroud attached at an outer end of the impeller blade. There is an axially-elongated annular seal element disposed at an axial end of the inducer shroud that provides sealing between the inducer shroud and the impeller shroud.

A pump includes a shaft that is rotatable about a central axis. An inducer is mounted on the shaft and has an inducer blade and inducer shroud attached at an outer end of the inducer blade. An impeller is mounted on the shaft downstream of the inducer and has an impeller blade and an impeller shroud attached at an outer end of the impeller blade. There is an axially-elongated annular seal element disposed at an axial end of the inducer shroud that provides sealing between the inducer shroud and the impeller shroud.

A self-priming assembly for a multi-stage pump is provided. The self-priming assembly can have a first diffuser, a second diffuser, and an impeller. The first and second diffusers each include a central portion, a diffuser axis, an arcuate channel within the central portion, and a passage extending through the central portion. The first diffuser and the second diffuser are configured to be combined and receive the impeller therebetween with the first diffuser axis, the second diffuser axis, and the impeller axis aligned.

A self-priming assembly for a multi-stage pump is provided. The self-priming assembly can have a first diffuser, a second diffuser, and an impeller. The first and second diffusers each include a central portion, a diffuser axis, an arcuate channel within the central portion, and a passage extending through the central portion. The first diffuser and the second diffuser are configured to be combined and receive the impeller therebetween with the first diffuser axis, the second diffuser axis, and the impeller axis aligned.

A pump includes a housing, a process stream input, a process stream output, a power stream inlet, and a rotor. The rotor comprises an impeller, a shroud, and a turbine. The impeller comprises fluid motive elements positioned about a central axis of the rotor and extending outward to the shroud. The turbine comprises runners formed on an outwardly facing surface of the shroud of the rotor. The shroud extends radially about the fluid motive elements of the impeller. The rotor is rotatably supported within the housing. The runners cause the rotor to rotate when the power stream flows through a fluid path impinging the runners thereby transferring energy from the flow of the power stream received through a power stream inlet into rotational energy of the fluid motive elements of the impeller to propel the process stream from a process stream input out a process stream output.

An electric centrifugal pump includes a water pump shell, a water sealing bearing, a water pump impeller, a spring washer, an inner motor cover, a bearing pedestal, a front rotor bearing, a motor stator, a motor rotor, a shaft of the motor rotor, a rear bearing of the motor rotor, a leading impeller, a leading impeller cover, a water pump driving control panel, a controller cover and a motor shell, and an internal forced cooling system is formed by the water inlet cavity of the water pump, an axial through hole of the shaft of the motor rotor, the leading impeller, a leading impeller cavity of the leading impeller, a spiral overflowing hole of the inner motor cover, a rotor cavity, a spiral overflowing hole of the bearing pedestal and the water pump impeller which are sequentially communicated.

A multistage centrifugal pump for conveying a fluid includes a pump housing with an inlet to receive the fluid and an outlet to discharge the fluid, a first stage impeller and a last stage impeller to convey the fluid from the inlet to the outlet, a shaft to rotate the first stage impeller and the last stage impeller about an axial direction, a suction chamber arranged upstream of the first stage impeller and in fluid communication with the inlet, a recirculation path for the fluid including a return opening and extending from the return opening to the suction chamber, the return opening located at or in the flow path downstream of the first stage impeller and upstream of the last stage impeller, and a flow control rod disposed in the recirculation path, the flow control rod to adjust a recirculation flow through the recirculation path into the suction chamber.

This relates to apparatus that can form dilute aqueous firefighting compositions from an aqueous concentrate.