Failure Analysis And Prevention Research Of The Navy Bass Tube Of The Condenser In Power Plant

Condenser is a large-scale heat exchanging equipment in thermal power plant,and its function is making the low-temperature steam condense into water after turbine so that the efficiency of the heat cycle can be improved. Due to their large volume of the condenser, large number of the brass ,complex structure, the harsh operating conditions and the thickness of the brass wall only about 1 mm, perforation will occur easily and result in the condenser pipe's leaking.The corrosion and leakage of condenser pipe will cause steam turbine's corrosion, scaling and salt, directly threating to generating units'running safely and economically. Therefore the study on corrosion mechanism and protection of the condenser pipe will be the center contents of this paper.At present, in our country most of condenser tubes used for heat exchanging is made of the navy brass. Research shows that the main forms of the condenser brass's corrosion are as follows: zinc corrosion, brush erosion-corrosion, stress corrosion cracking, pitting, corrosion, and sediments corrosion and so on. As to different forms of corrosion, the corrosion mechanism is different, anti-corrosion measures are different.Comprehensive anti-corrosion measures are taken on the research of the method of condenser tube's protection, including the treatment of cooling circulation water, the corrosion rate of the brass is reduced;by adding the anti- corrosion into the cooling water ,and improving the operating conditions of the condenser; making film on the surface of the condenser brass; imposing cathodic protection and so on.This paper introduces the method of cathodic protection of sacrificial anode.