Anti-cavitation protection device of feedwater pump

Abstract

The invention discloses an anti-cavitation protection device of a feedwater pump, which comprises two pressure detection units, a difference value comparison unit and a control system. The difference value comparison unit is used for comparing the difference value of signals detected by the two pressure detection units and comparing and judging a difference value comparison result with a set protection value Dp=NpSH* Rhog, the control system is used for controlling the feedwater pump to trip according to a comparison and judgment result of the difference value comparison unit and carrying out cavitation protection, the two pressure detection units are used for respectively detecting the suction inlet pressure of the feedwater pump and the internal pressure of a deaerator in real time, and the difference value comparison unit and the control system are connected and synchronously transmit the difference value comparison result to the control system. The invention has reasonable design, simple structure, convenient arrangement and real-time, dynamic and accurate reflection of the practical operation working conditions of the feedwater pump, is more scientific, reasonable and reliable than the traditional cavitation protection, and effectively overcomes the defects of necessary big-head booster pump arrangement, easy cavitation protection malfunction, poor use effect, and the like of a traditional feedwater pump.

Description

technical field [0001] The invention belongs to the technical field of cavitation protection for feed water pumps, in particular to a cavitation protection device for feed water pumps. Background technique [0002] The feed water pump set is one of the important equipment in thermal power plants, and centrifugal pumps are mostly used. In actual use, due to the high speed and large flow rate of the feed water pump, it is easy to cavitate, so in order to prevent cavitation, the feed water pump is usually equipped with an anti-cavitation protection device, that is, when cavitation occurs, the inlet pressure protection action of the feed water pump trips, To prevent cavitation of the feed pump. At present, the feed water pumps all adopt the anti-cavitation protection method of tripping when the inlet pressure is low (specifically, the switching value of two out of three). The protection value) is usually 0.8 ~ 1.4Mpa. During use, when the inlet pressure of the feed water pump...

AI Technical Summary

Problems solved by technology

[0008] The technical problem to be solved by the present invention is to provide an anti-cavitation protection device for feed water pumps, which has reasonable design, simple structure, convenient layout, good use effect, safe and reliable working performance, and real-time and accurate performance. It reflects the operating conditions of the feed water pump, and effectively overcomes the defects and deficiencies of the existing feed water pump protection methods, such as large front pump head, prone to cavitation protection misoperation, and poor use effect.

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