A drive unit has a first electric rotary machine and a second electric rotary machine as well as a first shaft and a second shaft. The first electric rotary machine is arranged at least partly radially and axially within an area radially delimited by the second electric rotary machine, and the stator of the first electric rotary machine and the stator of the second electric rotary machine are mechanically fixed to each other. The drive unit comprises a coolant supply device which is arranged adjacently to the stators in the axial direction and by means of which coolant can be supplied axially between and/or into the stators.

A drive unit has a first electric rotary machine and a second electric rotary machine as well as a first shaft and a second shaft. The first electric rotary machine is arranged at least partly radially and axially within an area radially delimited by the second electric rotary machine, and the stator of the first electric rotary machine and the stator of the second electric rotary machine are mechanically fixed to each other. The drive unit comprises a coolant supply device which is arranged adjacently to the stators in the axial direction and by means of which coolant can be supplied axially between and/or into the stators.

An enclosure for a genset comprises a container defining an internal volume for housing the genset. The container comprises a container floor, a container roof, a pair of container sidewalls disposed parallel to a longitudinal axis of the container, and a pair of container endwalls disposed at longitudinal ends of the container. A side cap is positioned parallel to each of the pair of container sidewalls along a longitudinal length of the container, each of the side caps sealed to edges of the corresponding container sidewall so as to define an acoustic cavity therebetween.

An enclosure for a genset comprises a container defining an internal volume for housing the genset. The container comprises a container floor, a container roof, a pair of container sidewalls disposed parallel to a longitudinal axis of the container, and a pair of container endwalls disposed at longitudinal ends of the container. A side cap is positioned parallel to each of the pair of container sidewalls along a longitudinal length of the container, each of the side caps sealed to edges of the corresponding container sidewall so as to define an acoustic cavity therebetween.

The present disclosure provides a fracturing equipment. The fracturing equipment includes: a plunger pump, a main motor and a noise reduction device. The plunger pump is used for pressurizing liquid. The main motor is connected to the plunger pump by transmission for providing driving force to the plunger pump. The noise reduction device is constructed as a cabin structure and covers outside the main motor and isolates the main motor from the plunger pump. With the fracturing equipment according to the present disclosure, the fracturing equipment is driven by the main motor with relatively low noise during operation. The noise reduction device isolates the main motor from the outside, which can effectively reduce the noise intensity transmitted to the outside during operation, thereby achieve the effect of noise reduction. In addition, the plunger pump is isolated from the main motor by the noise reduction device, thus realizing isolation of high-pressure dangerous areas and ensuring safe operation.

A vertical electric machine comprises a specific structure that defines a double box construction for normalizing the vertical electric machine structure such that its two reed critical frequencies occur at a same frequency. The double box construction includes a first stiffness member having a first side wall in a lateral “X” direction and a second stiffness member having a second side wall in a lateral “Y” direction such that the second side wall is rotated 90 degrees relative to the first side wall. The first stiffness member and the second stiffness member are configured to produce equal stiffness in both lateral directions “X” and “Y”.

A vertical electric machine comprises a specific structure that defines a double box construction for normalizing the vertical electric machine structure such that its two reed critical frequencies occur at a same frequency. The double box construction includes a first stiffness member having a first side wall in a lateral “X” direction and a second stiffness member having a second side wall in a lateral “Y” direction such that the second side wall is rotated 90 degrees relative to the first side wall. The first stiffness member and the second stiffness member are configured to produce equal stiffness in both lateral directions “X” and “Y”.

The invention relates to an electrical machine having a rotor (1), a stator (2) radially surrounding the rotor, and a housing (4) radially surrounding the stator. In order to minimize stresses in the housing and nonetheless decrease the tendency of the stator to torsional vibrations, the stator is connected to the housing at least at one end in a radially and torsionally rigid but axially movable manner, for example, by way of an axially compliant material area. The electrical machine can, in particular, be a motor spindle in a gear finishing machine.

Electric compressor 1 has electric motor 10 housed in casing 40, the motor including stator 2 having yoke portion 2a and plural tooth portions 2b, and rotor 3 disposed radially inside stator 2. Protrusion 41f protrudes at plural circumferential positions of inner periphery 41a1 of casing 40, which has protruding end surface 41f1 contacting an outer periphery of yoke portion 2a with width larger than tooth portion 2b. Contact tooth back portion 2a11 contacts protruding end surface 41f1, out of plural tooth back portions 2a1 each disposed behind tooth portion 2b as part of the outer periphery of yoke portion 2a, is formed in a region except both edge portions 41h of protruding end surface 41f1 in a circumferential direction within a circumferential angle range θ in which the protruding end surface 41f1 is located.

Electric compressor 1 has electric motor 10 housed in casing 40, the motor including stator 2 having yoke portion 2a and plural tooth portions 2b, and rotor 3 disposed radially inside stator 2. Protrusion 41f protrudes at plural circumferential positions of inner periphery 41a1 of casing 40, which has protruding end surface 41f1 contacting an outer periphery of yoke portion 2a with width larger than tooth portion 2b. Contact tooth back portion 2a11 contacts protruding end surface 41f1, out of plural tooth back portions 2a1 each disposed behind tooth portion 2b as part of the outer periphery of yoke portion 2a, is formed in a region except both edge portions 41h of protruding end surface 41f1 in a circumferential direction within a circumferential angle range θ in which the protruding end surface 41f1 is located.