Questions regarding the bidding for water pumps.
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What I would like to ask is that I am currently working on a bid for a water pump. The specific water pumps are the boiler feed water pumps, circulation water pumps, condensate water pumps, etc., used in small gas-fired power plants. It seems that they all belong to the category of centrifugal pumps, with the boiler feed water pump being a multi-stage centrifugal pump. The bid document includes a performance rating for water pumps; what aspects should be taken into consideration for this rating? Create a gap? For example, efficiency, must there be a net positive suction head? Are there any other indicators? Furthermore, what tests are generally conducted during performance testing? I don’t know much about it; I hope the original poster can give me some guidance! Thank you.
This post was last edited by hlcl on 2016-10-18 07:58. The Qrated/Qbep value should be greater than 0.8 and less than 1.2, indicating a preferred working area. The head increase is preferably greater than 1.1 and less than 1.2 ； For D/L, the shaft diameter at the bearing/bearing span should preferably be greater than 0.04 ； When using the largest impeller, is the head margin greater than 5% of the rated value? ； Don’t forget about the performance report as well. The NPSH ratio is generally required to be less than 13,000 m3/h, rpm, m
That’s so professional. I don’t quite understand. . . One still needs to study with dedication*. May I ask if these are based on accumulated work experience or on certain criteria? Also, these indicators should be able to be determined through experiments or tests; otherwise, every equipment manufacturer will claim to be able to meet them in order to win the bid, since you don’t know how to verify them anyway. . .
Our requirements for negotiating with foreigners. These are some of the requirements from API610 and the design institute.
Hello! The Q-rated/Qbep value you mentioned should be greater than 0.8 and less than 1.2, indicating the preferred operating area. The head increase is preferably greater than 1.1 and less than 1.2 ； For D/L, the shaft diameter at the bearing/bearing span should preferably be greater than 0.04 ； When using the largest impeller, is the head margin greater than 5% of the rated value? ； Don’t forget about the performance report as well. The cavitation specific speed is generally required to be less than 13,000 m3/h. Would it be better to use parameters such as rpm and m as technical requirements? No W-score condition? How should it be handled as a scoring criterion? For example, a score is given if 0.8＜Qrated/Qbe＜1.2, and no score is assigned for other ranges? Is that how it should be set up? Also, can the head increase, Q rated/Qbep, and cavitation specific speed be determined through performance tests? If it cannot be determined, it is not suitable as a scoring criterion, as it is impossible to verify whether they cheated during bidding. Thank you so much for your guidance!
Qrated/Qbep – this is particularly important. All of the above parameters can be determined. Give these specifications to the manufacturer and have them meet them. If the first condition is not met, it is not recommended for use. Other aspects can be discussed, and the manufacturer can make adjustments as well.
Test: Unobserved test, Observed test, Dynamic rotor balancing (G2.5), Y Hydrostatic test, Y Necessary net positive suction head test, Y Performance testing, Y Mechanical operation test of the complete unit, excluding LOS, Y Cleanliness before final assembly, Y