脱硫装置搅拌器叶轮再制造及防腐耐磨涂层的应用研究

Application Research on Remanufacturing and Wear and Corrosion Resistant Coatings of Stirrer's Impeller for Desulphurization Device

再制造具有优质、高效、节能、节材及环保的特点,目前在机械制造领域已引起高度重视,脱硫装置吸收塔搅拌器叶轮的再制造具有十分显著的经济效益及节能、节材效果。本文在分析脱硫装置吸收塔搅拌器叶轮失效机理的基础上,介绍了搅拌器叶轮在再制造中的主要工艺过程,重点阐述了搅拌器叶轮表面强化时的热喷涂涂层的材料与制备工艺的选择。研究及使用表明：采用微弧仿形堆焊能有效恢复叶轮的尺寸及形状;NiCrMo自熔性合金喷熔层表现出良好的抗汽蚀性能,汽蚀率仅为微米WC-12Co和亚微米WC-12Co涂层的35%左右。搅拌器叶轮再制造费用一般仅为新叶轮的30%~40%,但其防腐耐磨性优于新叶轮,具有显著的经济效益和社会效益。

Remanufacturing has characteristics of high quality, high efficiency, energy-saving, material-saving and environment protection, which currently has been aroused great attention in the field of mechanical manufacturing. The remanufacturing of absorption tower stirrer＇s impeller for desulphurization device is of very significant economic benefits, energy-saving and material-saving effects. Based on the analysis of the failure mechanisms of absorption tower stirrer＇s impeller for desulphurization device, the main remanufacturing processes of stirrer＇ s impeller were introduced, and the coating materials and the process choice of thermal spray in the surface strengthening of the impeller were also introduced emphatically in the paper. Research and application have indicated that the dimensions and shapes can be repaired effectively by micro-arc profile modeling surfacing; NiCrMo spraying and fusing coating possesses the excellent anti-cavitation performance, and cavitation rate is only approximately 35% of micron WC-12Co and sub-micron WC-12Co coatings. The resistance of the impeller＇s wear and corrosion after remanufacturing is more excellent than the new impeller though the remanufacturing cost of the impeller is 30%-40% only in comparison with the new impeller. Therefore the remanufacturing of stirrer＇ s impeller possesses important economic and societal benefits.