Research on the New Low Temperature Self-Protective Paste Boronizing Processes of Thermal Power Plant Economizer Pipe

摘要

Power plant boiler economizer pipe tend to crack rapidly due to the erosion of high temperature flue gas.In this paper,the power plant boiler economizer pipe (annealing 20 steel) was chosen as the research materials,three new formulations of self-protective paste in which quartz powder,fly ash and coal gangue were as the main ingredients were investigated,what's more,the low temperature self-protective paste boronizing technology with the rare earth added was studied.The experimental results show that the quartz powder,fly ash and coal gangue protective layer sintered at the boride temperature have the virtues of high strength,good sealing and easier peeling off,and these protective layers also brought good boronizing effect.9wt％ rare earth addition can bring good boronizing effect,when the boronizing temperature down wn to 700 ℃,the rare earth added self-protection paste boronizing process can still achieve boronizing layer.The wear-resisting and corrosion resistant performance of the economizer pipe after boronizing process obviously improved.