Balance drums and systems for managing axial forces for pumps and related systems and methods
AssigneeFlowserve US Company
InventorsDennis W. Chalmers, Mina M. Botrous, Christopher Finley
Life of this patent
Estimating the term…
Abstract
A cryogenic pump may include a housing and a drive shaft positioned in the housing. The cryogenic pump may include at least one pump stage positioned in the housing, the at least one pump stage comprising an impeller coupled to the drive shaft. The cryogenic pump may include a balance drum coupled to the drive shaft and positioned in the housing. The cryogenic pump may additionally include a motor comprising a rotor slidably coupled to the drive shaft, the drive shaft configured to rotate with the rotor and move in an axial direction relative to the rotor and the housing during operation of the cryogenic pump.
Claims20
A cryogenic pump, comprising:
- a housing;
- a drive shaft positioned in the housing;
- at least one pump stage positioned in the housing, the at least one pump stage comprising an impeller coupled to the drive shaft;
- a balance drum coupled to the drive shaft and positioned in the housing;
- and
- a motor comprising a rotor slidably coupled to the drive shaft, the drive shaft configured to rotate with the rotor and move in an axial direction relative to the rotor and the housing during operation of the cryogenic pump, such that the drive shaft is enabled to move axially independently of the rotor.
A cryogenic pump, comprising:
- a motor having a rotor;
- and
- a balance drum comprising:
- a central aperture sized to be coupled to a drive shaft of the cryogenic pump such that the drive shaft with the balance drum coupled thereto is configured to independently move axially relative to the rotor of the motor that rotates the drive shaft;
- an arcuate serrated side surface configured to define one or more fluid flow channels between the arcuate serrated side surface of the balance drum and a radially adjacent portion of the cryogenic pump;
- a serrated axial end surface configured to define a plurality of additional fluid flow channels between the serrated axial end surface of the balance drum and an axially adjacent portion of the cryogenic pump;
- a first outer channel positioned between a first radial side of the serrated axial end surface and the arcuate serrated side surface;
- and
- a second inner channel positioned between a second radial side of the serrated axial end surface and the central aperture.
A method of operating a cryogenic pump, the method comprising:
- rotating a drive shaft of the cryogenic pump having a plurality of impellers fixedly coupled to the drive shaft with a rotor of a motor;
- applying an axial force to the drive shaft;
- and
- sliding the drive shaft in an axial direction relative to the rotor of the motor while rotating the drive shaft with the rotor of the motor in response to the axial force, such that the drive shaft moves axially independently of the rotor.
A method of customizing a balance drum for a cryogenic pump, the method comprising:
- providing a balance drum having a serrated axial end surface;
- determining a desired pressure difference across the balance drum during operation of the cryogenic pump;
- removing a portion of the serrated axial end surface to provide a customized balance drum designed to achieve the desired pressure difference across the balance drum during operation of the cryogenic pump;
- and
- mounting the customized balance drum to a drive shaft such that the drive shaft with the customized balance drum coupled thereto is configured to move axially independently of a rotor of a motor that rotates the drive shaft with the customized balance drum coupled thereto.
Dependencies are inferred from the claim text.