Author: N.M. Podvolotsky
Abstract
The article considers comparison of parameters in feed regulation of centrifugal and a screw pump with bypass method via discharge characteristics to determine the ship tanks stripping efficiency. For comparison assessment of parameters, the scheme with annular bypass pipeline has been used. The comparison has been made for two regulation modes: with full-opened and half-opened bypass valve. The capacity and it is regulation range for full-opened and half-opened valve are higher for centrifugal pumps. In case of short tank stripping time in relation to main pump work mode the deciding factor is stripping time, meaning the efficiency of pumps can be neglected. Based on comparison of centrifugal and screw pumps parameters working on main mode and stripping, the preference has been given to centrifugal pump. Its disadvantage is in lack of self-suction, which is resolved with technical devices, removing air prior to entering the pump while stripping.
Keywords: centrifugal and screw pumps, tank stripping, discharge characteristic, bypass capacity regulation, annular bypass pipeline, work modes, comparison of parameters, stripping time, stripping efficiency, provision of self-suction.
References
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About author:
N.M. Podvolotsky, DSc, professor, Admiral Makarov State University of Maritime and Inland Shipping, St. Petersburg
Issue: 68/69 (2022)
For citation: N.M. Podvolotsky. Comparison of parameters in feed regulation of centrifugal and screw pumps. Research Bulletin by Russian Maritime Register of Shipping. 2022, No. 68/69, pp. 71-76.
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