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渣漿泵怎么通過汽蝕調節流量

汽蝕調節僅用于凝結水泵中的調節，調節時把架的出口調節調全開，當汽機負荷變化時，也就是凝汽器的凝汽量相應變化時，供水泵進水位的變化來調節泵的流量，達到汽輪機的排氣量的變化與水泵輸水量自動平衡的目的。它的調節原理如圖4-11、圖4- 12所示。泵的倒灌高度Hg，為設計工況下泵不發生汽蝕的最小高度，這時泵的工作點如圖4-12中的A點，當汽輪機負荷減少時，排氣量也減少，倒灌高度不能維持Hg，使發生汽蝕，Q-H性能曲線驟然下降，而裝置揚程曲線沒有改變，于是泵的工作點變為A1，泵的流量為QA。如果繼續減小負荷，繼續減少排氣量，倒灌高度再往下降，泵的工作點相應變為A2，A3.....，泵的流量為QA，  ....，直至達到新的平衡。這就是泵汽蝕調節原理。
汽蝕調節時應注意如下問題:

(1)凝結水泵的Q-H性能曲線應比較平坦一些為好，這樣泵在進行汽蝕調節時工作比較穩定。  

(2)應避免汽輪機長期在低負荷下運行，而造成泵長時間汽蝕下運行降低泵的壽命，如果需要長期在低負荷下運行，應開啟凝結水泵的再循環，使熱井水位不致過低。

(3)泵經常會在汽蝕下工作，葉輪容易汽蝕破壞，應采用抗汽蝕材料的葉輪。渣漿泵廠家

How to regulate the flow of slurry pump through cavitation

The cavitation regulation is only used for the regulation in the condensate pump. During the regulation, the outlet regulation of the rack is fully opened. When the load of the turbine changes, that is to say, when the condensate of the condenser changes correspondingly, the change of the inlet water level of the water supply pump regulates the flow of the pump, so as to achieve the purpose of automatic balance between the change of the exhaust volume of the turbine and the water delivery volume of the pump. Its adjustment principle is shown in Fig. 4-11 and Fig. 4-12. The pouring height Hg of the pump is the minimum height of the pump without cavitation under the design working condition. At this time, the working point of the pump is as shown in point a in Figure 4-12. When the load of the turbine is reduced, the exhaust volume is also reduced, and the pouring height cannot maintain Hg, resulting in cavitation. The Q-H performance curve suddenly drops, but the installation head curve does not change, so the working point of the pump becomes A1, and the flow of the pump is QA. If the load continues to be reduced, the exhaust volume continues to be reduced, and the pouring height goes down again, the working point of the pump correspondingly becomes A2, A3,..., and the flow of the pump is QA,..., until the new balance is reached. This is the principle of pump cavitation regulation.

Attention shall be paid to the following problems during cavitation regulation:

(1) the Q-H performance curve of condensate pump should be relatively flat, which is better, so that the pump works stably during cavitation regulation.

(2) long term operation of steam turbine under low load shall be avoided, which will lead to long-term operation of pump under cavitation and reduce the service life of pump. If long-term operation under low load is required, recycle of condensate pump shall be started, so that the water level of hot well will not be too low.

(3) the pump often works under cavitation, and the impeller is easy to be damaged by cavitation. The impeller made of anti cavitation material shall be used. Slurry pump