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.

The present invention provides a quick startup device for a centrifugal pump. The device includes an upper self-priming chamber, a lower self-priming chamber, and an inlet pipe sequentially arranged from top to bottom. The upper self-priming chamber and the lower self-priming chamber are integrally mounted on the inlet pipe. A main shaft and a hexagonal partition member rotatably mounted on the main shaft are arranged on an axis of the upper self-priming chamber. A blade tip of each partition plate is closely attached to an inner wall surface of the upper self-priming chamber. Three identical accommodation grooves are provided on an inner side of the upper self-priming chamber. A spring and a separation baffle are arranged in each accommodation groove, an exhaust hole is provided on one side of each accommodation groove, and an air intake pipe is provided on the other side of each accommodation groove.

A method of priming a pump includes supplying lubricant, via a priming flow path, into an interface defined between a first part of a shaft of the pump and a second part of the shaft coaxially engaged with the first part of the shaft to define the pump, the first part of the shaft rotatable about a rotation axis relative to the second part of the shaft, and supplying lubricant into the interface via a lubrication flow path that is different from the priming flow path. A method of lubricating an aircraft motor of an aircraft engine, and a machine for an aircraft engine are also described.

A centrifugal pump (7), with one or more pumping stages, includes a pressure controlled valve (15) inside the pump (7) for supporting self-priming, the pressure controlled valve (15). The pressure controlled valve (15) includes a pretensioned leaf spring (17) and a valve seat (18). The leaf spring (17) has an opened position and a closed position. In the open position the leaf spring (17) is distanced from the valve seat (18). In the closed position the leaf spring (17) closes the valve seat (18). The leaf spring (17) and valve seat (18) are arranged for soft closing.

An impeller includes a disk-shaped hub and a plurality of vanes provided radially on the surface of the hub. The plurality of vanes are formed in a whirling pattern about the center of rotation of the impeller, and each of the vanes has an outer peripheral surface facing the inner peripheral surface of the volute. A rotational-direction rear end portion of the outer peripheral surface of each of the vanes has a recessed step surface formed thereon. The rotational-direction rear end of the recessed step surface of each of the vanes is formed to define an edge shape with respect to a rotational-direction rear end surface of the vane.

A volute of a centrifugal pump includes a proximate section. The proximate section includes: an outer peripheral portion having a tapered shape such that, within a range of a rotational trajectory of each of vanes provided on an impeller, the outer peripheral portion gradually spreads out in a direction axially away from the vane; and an inner peripheral portion having a tapered shape such that, within the range of the rotational trajectory of each of the vanes, the inner peripheral portion tapers in the direction axially away from the vane. The inner and outer peripheral portions are spaced apart from each other with a flat proximal opposed surface portion therebetween. The opposed surface portion is opposed to respective axial end surfaces of vanes of the impeller. The volute also includes a peripheral wall surrounding the peripheral surfaces of the vanes.

A pump with high performance and cleanability includes a casing having a smaller volute and a larger volute; a space between an outer circumference of an impeller and a starting end of the smaller volute being greater than that of the larger volute, generating a circulating flow of self-priming water from the smaller volute to the larger volute; and a diffusing part of the larger volute being formed into an upright, cylindrical self-priming water separating chamber guiding the self-priming water from the smaller volute to flow in for air-water separation. An inner circumference part of the casing is formed concentric with the outer circumference of the impeller with a predetermined space therebetween; defining members are protrusively disposed on the inner circumference part of the casing so as to define the shapes of the two volutes; and the self-priming water separating chamber is made attachable to and detachable from the casing.

A centrifugal pump device has at least one impeller (16), a circulation connection between a delivery side (22) of the at least one impeller (16) and a suction side (20) of the at least one impeller (16), and a valve arrangement (30, 46) in said circulation connection (44, 54). The valve arrangement (30, 46) has a first valve mode providing a pressure dependent shut-off valve (46) in the circulation connection. The valve arrangement (30, 46) allows a change between the first valve mode and at least one further valve mode. The at least one further valve mode provides at least one fixed closing degree of the circulation connection (44, 54).

Included are electric submersible pump assemblies, methods of use, and systems incorporating said electric submersible pump assemblies. An example electric submersible pump assembly comprises an electric submersible pump comprising a pump intake, a storage chamber in fluid communication with the discharge side of the electric submersible pump, and a tubing configured to allow for fluid communication between the pump intake and the storage chamber such that fluid may flow from the storage chamber into the pump intake.

A quick no-water startup apparatus for a centrifugal pump includes, from top to bottom in sequence, one-way passages (1), a self-priming chamber housing (41), sliding devices (5), a self-priming chamber (4), chamber partition plates (2) a concave-convex impeller (3), inlet channels (6) connected on two sides of the self-priming chamber (4), a spring device (7) of an upper-side x-shaped gas-liquid separation device, the upper-side x-shaped gas-liquid separation device (8), upper and middle-side gas-liquid separation device connecting shafts (9), a middle-side gas-liquid separation device (10), lower-side backflow-type gas-liquid separation devices (11), v-shaped backflow channels (122), an inverted v-shaped inlet channel (121), and an inlet. The quick no-water startup apparatus of the present invention enables the centrifugal pump to directly enter a normal operating condition after no-water startup, and 36 times of air exhaust can be completed while the concave-convex impeller (3) in the self-priming chamber (4) rotates by a circle in the early stage. Besides, the apparatus is provided with the upper, middle, and lower gas-liquid separation devices to fully realize separation of gas and liquid, so that gas can be exhausted more quickly and the chamber is filled with water. Therefore, the working efficiency is significantly improved and the operation process is greatly simplified.