For three-screw pumps, the structural selection should be based on the pump's installation and operating conditions, referring to its series and type, and following these principles:
For conveying lubricating oils at temperatures below 80℃, select a screw pump with an internal bearing structure.
For conveying poorly lubricating media or at temperatures exceeding 80℃, select a screw pump with an external bearing structure.
For conveying media with poor flowability and high viscosity, or when heating or insulating the conveyed medium, select a screw pump with a double-layer heated pump body structure.
For conveying high-temperature media, select a pump made of high-temperature resistant materials.
In addition to the above structural selection principles, the following key components should also be considered when selecting a screw pump: the material combination should be determined based on the properties of the conveyed medium; the shaft seal can be either a mechanical seal or a packing seal as needed, and the two structures are interchangeable; for low-speed pumps like single-screw pumps, the drive method includes direct-drive with a low-speed motor, geared motor drive, and continuously variable transmission (CVT) motor drive; the selection of the bushing rubber material directly affects the bushing life, and a suitable rubber material should be selected based on the characteristics of the medium.
