【Daily Question: Pump Equipment】Multiple-choice Question 2018.11.22

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This post was last edited by 3983596_FPPZ on 2018-11-24 08:37. Regarding the balance of axial forces in the rotor system of centrifugal pumps, which of the following statements are correct? (Multiple choice) A. The double-suction pump design enables the balance of axial forces. B. Pumps with double volute channels can balance axial forces. C. Multi-stage pumps achieve axial force balance by using symmetrically arranged impellers. D. The radial guide vanes in the flow channels outside the impellers within the pump can balance axial forces. Answer: AC. A. Double-suction pumps have double-suction impellers that draw in fluid symmetrically from both sides, which allows the axial forces generated by the impellers to be balanced; such pumps are commonly used for high-flow applications. The B discharge passage features a double-volute pump body, which is designed to ensure that the shape of the flow channel around the outer circumference of the impeller is symmetrical, thereby allowing for a symmetrical distribution of the circumferential pressure and balancing the radial forces of the pump. In C multi-stage pumps, an even number of impellers are arranged symmetrically on either side (face to face or back to back), so that the axial force generated by each impeller is balanced by another impeller, thereby balancing the overall axial force. The D pump features a structure with radial vanes, which enables even distribution of the circumferential pressure on the outer periphery of the impeller and balances the radial forces; this type of design is commonly found in the vanes of BB4 (segmented multi-stage pumps). Therefore, the answer is AC