A device is disclosed including a wear ring formed as a hollow cylinder with an inside diameter and an outside diameter. The hollow cylinder may have multiple holes through at least a portion of the wear ring from the inside diameter towards the outside diameter. The multiple holes may be passages between the inside diameter and the outside diameter that allow fluid under pressure to pass between the inside diameter and the outside diameter through the multiple holes.

A magnetic bearing for a turbomachine includes a stator fixable to a structure of a turbomachine; a rotor magnetically coupled to the stator and defining a rotation axis, the rotor having a front central surface, a rear central surface opposite to the front central surface and an external surface with respect to the rotation axis; the rotor is provided with an internal channel configured to displace cooling fluid.

A high speed, rotary lobe gear pump assembly is provided which combines a positive displacement lobe gear pump having wipers with a centrifugal pump utilizing an impeller. The centrifugal pump feeds high pressure fluid flow directly into the lobe gear pump allowing the gear pump to rotate at high speeds without cavitation. The high speed capability of the pump assembly allows the lobe gear pump to operate without speed reduction gearing for the motor shaft.

A high speed, rotary lobe gear pump assembly is provided which combines a positive displacement lobe gear pump having wipers with a centrifugal pump utilizing an impeller. The centrifugal pump feeds high pressure fluid flow directly into the lobe gear pump allowing the gear pump to rotate at high speeds without cavitation. The high speed capability of the pump assembly allows the lobe gear pump to operate without speed reduction gearing for the motor shaft.

A fluid transfer pump assembly is provided that includes an electronic device enclosure, a bore, and a vent pin. The electronic device enclosure includes a wall separating an interior from an exterior of the explosion-proof fluid transfer pump assembly. The electronic device enclosure includes a bore extending through the wall of the electronic device enclosure from the interior of the electronic device enclosure to the exterior of the explosion-proof fluid transfer pump assembly. The bore is formed by at least one peripheral surface extending from the interior of the electronic device enclosure to the exterior of the explosion-proof fluid transfer pump assembly. The vent pin extends into the bore. The vent pin fills space within the bore and engages the at least one peripheral surface except that at least one portion of a pin surface of the vent pin is spaced apart from at least one portion of the at least one peripheral surface of the bore.

A retaining device for an impeller of a centrifugal pump, including: a pump shaft with a recess formed substantially parallel to the axis of rotation of the pump shaft; a fastening bolt, which is insertable into the recess such that a first channel is defined between the inserted fastening bolt and the pump shaft and which is connected to the pump shaft on one end thereof and provides a retainer for fixing the impeller on the other end thereof; wherein the pump shaft includes at least one further channel extending from the circumferential surface of the pump shaft up to and into the recess and allowing the first channel to be emptied.

A retaining device for an impeller of a centrifugal pump, including: a pump shaft with a recess formed substantially parallel to the axis of rotation of the pump shaft; a fastening bolt, which is insertable into the recess such that a first channel is defined between the inserted fastening bolt and the pump shaft and which is connected to the pump shaft on one end thereof and provides a retainer for fixing the impeller on the other end thereof; wherein the pump shaft includes at least one further channel extending from the circumferential surface of the pump shaft up to and into the recess and allowing the first channel to be emptied.

Apparatus and associated methods relate to simultaneously pumping and measuring density of an aircraft fuel. The aircraft fuel is pumped by a centrifugal pump having an impeller. A rotational frequency of the impeller is determined while the centrifugal pump is pumping the aircraft fuel. Flow rate of the aircraft fuel through the centrifugal pump is sensed. Pressure of the aircraft fuel is measured at two different points within or across the centrifugal pump or a differential pressure is measured between the two different points while the centrifugal pump is pumping the aircraft fuel. Density of the aircraft fuel is determined based on a head-curve relation characterizing the centrifugal pump. The head-curve relation relates the fuel density to the rotational frequency, the flow rate, and pressures at the two different points or the differential pressure between the two different points.

An aero acoustic processing apparatus includes an aero acoustic processing machine (10) having a cyclone chamber (12) having an inlet (14) for receiving waste to be processed and an inlet (16) for an entraining gas in the form of air. A rotational drive apparatus in the form of an electric motor (18) is coupled to a shaft (20) to which an impeller (22) is coupled rotates the impeller (22) within an impeller housing (24) to draw the air and the waste material to be processed into the cyclone chamber (12) and through an axial inlet system (26) into the impeller (22) and impeller housing (24) and to expel the processed material through the impeller housing (24) radially through a transverse outlet.

An aero acoustic processing apparatus includes an aero acoustic processing machine (10) having a cyclone chamber (12) having an inlet (14) for receiving waste to be processed and an inlet (16) for an entraining gas in the form of air. A rotational drive apparatus in the form of an electric motor (18) is coupled to a shaft (20) to which an impeller (22) is coupled rotates the impeller (22) within an impeller housing (24) to draw the air and the waste material to be processed into the cyclone chamber (12) and through an axial inlet system (26) into the impeller (22) and impeller housing (24) and to expel the processed material through the impeller housing (24) radially through a transverse outlet.