Shaft assemblies, turbomachines, and methods of servicing a turbomachine are provided. A shaft assembly includes a first shaft having a first rabbet annularly defined therein. The first rabbet includes a first axially extending face and a first radially extending face. A second shaft coupled to the first shaft. The second shaft includes a second rabbet annularly defined therein and positioned opposite the first rabbet. The second rabbet includes a second axially extending face and a second radially extending face. A patch ring is mounted between the first rabbet and the second rabbet. The patch ring includes a main body positioned between and in contact with the first axially extending face and the second axially extending face. A first arm extends radially outward from the main body, and a second arm extends radially inward from the main body.

Shaft assemblies, turbomachines, and methods of servicing a turbomachine are provided. A shaft assembly includes a first shaft having a first rabbet annularly defined therein. The first rabbet includes a first axially extending face and a first radially extending face. A second shaft coupled to the first shaft. The second shaft includes a second rabbet annularly defined therein and positioned opposite the first rabbet. The second rabbet includes a second axially extending face and a second radially extending face. A patch ring is mounted between the first rabbet and the second rabbet. The patch ring includes a main body positioned between and in contact with the first axially extending face and the second axially extending face. A first arm extends radially outward from the main body, and a second arm extends radially inward from the main body.

The invention relates to a shaft for supplying air to a fuel cell, comprising a tubular body (12), at least sections of which are hollow, and which has a first component (14) and a second component (16) that are connected to one another at respective neighbouring axial end sections (14a, 16a), and wherein air can flow through a hollow space (12a) of the tubular body (12) for cooling components arranged next to the shaft (10). The invention also relates to a radial compressor (1). The invention further relates to a method for producing a radial compressor (1).

An electrical submersible well pump assembly has shaft couplings. One of the couplings has a lower hub that rotates in unison with the motor shaft and an upper hub that rotates in unison with the pump shaft. A helical spring clutch engages both hubs when the motor shaft is being driven by the motor. Ceasing driving rotation of the motor shaft causes the spring clutch to disengage from the upper hub, enabling the pump shaft to rotate the upper hub without rotating the lower hub.

An electrical submersible well pump assembly has shaft couplings. One of the couplings has a lower hub that rotates in unison with the motor shaft and an upper hub that rotates in unison with the pump shaft. A helical spring clutch engages both hubs when the motor shaft is being driven by the motor. Ceasing driving rotation of the motor shaft causes the spring clutch to disengage from the upper hub, enabling the pump shaft to rotate the upper hub without rotating the lower hub.

A pump apparatus (1) for use in mobile means of transport (100) such as semitrailers, tank trailers, tank semitrailers (101), tank trucks and trucks (102), has a drive motor (40) and a rotary piston pump (2) having two rotor units (10, 20) on rotatably mounted rotor shafts (11, 21), connected to rotor gear wheels (12, 22). A drive pinion (32) of a drive shaft (31) coupled to one of the rotor gear wheels (12) and is received in a recess (81) of the motor shaft (41).

A pump apparatus (1) for use in mobile means of transport (100) such as semitrailers, tank trailers, tank semitrailers (101), tank trucks and trucks (102), has a drive motor (40) and a rotary piston pump (2) having two rotor units (10, 20) on rotatably mounted rotor shafts (11, 21), connected to rotor gear wheels (12, 22). A drive pinion (32) of a drive shaft (31) coupled to one of the rotor gear wheels (12) and is received in a recess (81) of the motor shaft (41).

A system for hydraulically fracturing an underground formation in an oil or gas well, including a pump for pumping hydraulic fracturing fluid into the wellbore, the pump having a pump shaft, and an electric motor with a motor shaft mechanically attached to the pump to drive the pump. The system further includes a torsional coupling connecting the motor shaft to the pump shaft. The torsional coupling includes a motor component fixedly attached to the motor shaft and having motor coupling claws extending outwardly away from the motor shaft, and a pump component fixedly attached to the pump shaft of the pump and having pump coupling claws extending outwardly away from the pump shaft. The motor coupling claws engage with the pump coupling claws so that when the motor shaft and motor component rotate, such rotation causes the pump component and the pump shaft to rotate, thereby driving the pump.

A system for hydraulically fracturing an underground formation in an oil or gas well, including a pump for pumping hydraulic fracturing fluid into the wellbore, the pump having a pump shaft, and an electric motor with a motor shaft mechanically attached to the pump to drive the pump. The system further includes a torsional coupling connecting the motor shaft to the pump shaft. The torsional coupling includes a motor component fixedly attached to the motor shaft and having motor coupling claws extending outwardly away from the motor shaft, and a pump component fixedly attached to the pump shaft of the pump and having pump coupling claws extending outwardly away from the pump shaft. The motor coupling claws engage with the pump coupling claws so that when the motor shaft and motor component rotate, such rotation causes the pump component and the pump shaft to rotate, thereby driving the pump.

An electrical submersible well pump assembly (ESP) has a spring brake having helical turns mounted between the shaft and one of the housings. The spring brake allows free rotation of the shaft in a driving direction and stops the shaft from rotating in a reverse direction. The spring brake may have one end be affixed to the housing to rotate in unison in both directions. Alternately, the spring brake may have one end affixed to the shaft for rotation with the shaft. Further, the spring brake could be free of being connected to either the shaft or the housing. A shear member may be mounted between the shaft and the housing to prevent any rotation of the shaft during run-in.