【Daily Question: Pump Equipment】Weekly Summary 2018.11.25

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This post was last edited by 3983596_FPPZ on 2019-1-19 at 09:45. Monday (2018.11.19) https://bbs.hcbbs.com/thread-2154007-1-1.html The magnitude of the inlet pressure has a direct impact on which of the following parameters of a centrifugal pump? (AD) A. Outlet pressure B. Head C. Flow rate D. Cavitation E. Shaft power. Tuesday (2018.11.20) https://bbs.hcbbs.com/thread-2155320-1-1.html In the poem “Viewing the Lushan Waterfall” by Tang Dynasty poet Li Bai, there is a line that reads “The waterfall plunges down three thousand feet,” which indicates: (AD) A. Lushan is very high above sea level, so the water has great potential energy. B. Lushan is very high above sea level, so the water has great kinetic energy. C. The process of kinetic energy being converted into potential energy. D. The process of potential energy being converted into kinetic energy. Wednesday https://bbs.hcbbs.com/thread-2157096-1-1.html Which of the following statements about self-priming centrifugal pumps is correct? (ACD) A. Under standard atmospheric pressure, the ideal maximum priming height is 10.33 meters. B. A thinner inlet pipeline should be used; if the inlet pipeline is too thick, priming will not be possible. C. The priming time is related to the amount of air present in the inlet pipeline. D. The priming capacity is directly related to the net positive suction head available (NPSHr), and it has no direct relation to flow rate, head, or speed. Thursday (2018.11.22) https://bbs.hcbbs.com/thread-2159390-1-1.html Regarding the balance of axial forces in the rotor system of a centrifugal pump, which of the following statements is correct? (AC) A. The double-suction pump design can balance axial forces. B. Pumps with double volute channels can balance axial forces. C. Multi-stage pumps use symmetrically arranged impellers to balance axial forces. D. The radial guide vanes in the flow channels outside the impellers within the pump can balance axial forces. Friday (2018.11.23) https://bbs.hcbbs.com/thread-2161314-1-1.html Which of the following statements about magnetic pumps and shielded pumps is correct? (ABCD) A. Magnetic pumps utilize a magnetic field generated by permanent magnets. B. Shielded pumps utilize a magnetic field generated by electromagnetic windings. C. Both magnetic pumps and shielded pumps are completely leak-free pumps. D. Both magnetic pumps and shielded pumps with metal isolation sleeves suffer from metal eddy current losses. Saturday (2018.11.24) https://bbs.hcbbs.com/thread-2163102-1-1.html If the efficiency of a centrifugal pump is 65%, then which of the following statements is correct? (AB) A. An efficiency of 65% means that the medium receives 65% of the energy from the shaft power. B. An efficiency of 65% means that 35% of the shaft power is lost. C. An efficiency of 65% means that the medium receives 65% of the energy from the motor power. D. An efficiency of 65% means that 35% of the motor power is lost. This summary post gathers together the questions from the “One Question per Day – Pump Equipment” series over the past week; you can review them here without needing to reply with a score