Abstract:

At present, nitriding treatment is usually used for valve hardening in China. Nitriding process has the advantages of enhancing the service life of valve and improving the wear resistance of valve shaft sleeve. However, there are few studies on the application of the valve after pickling and passivation treatment in the production of hydrogen peroxide by anthraquinone method after nitriding process. In order to increase the research in this direction, this paper introduced several methods of nitriding the surface of valve rod and shaft sleeve, such as plasma nitriding, radio frequency nitriding, microwave nitriding, ion implantation and ion annihilation implantation, so as to increase the service life and wear resistance of valve rod and shaft sleeve. Through the overall pickling of the stem shaft sleeve of austenitic stainless steel three eccentric reducing butterfly valve after nitriding treatment, disassembly and inspection after pickling and soaking with hydrogen peroxide, the concentration, stability and iron ions of hydrogen peroxide with different soaking time were measured. According to the experimental results, it was concluded that the surface of the valve treated by nitriding process would contain a large amount of iron ions after pickling, and the existence of these iron ions would lead to the decomposition of hydrogen peroxide, reducing the concentration and stability of hydrogen peroxide, and thus it was not suitable for the production of hydrogen peroxide by anthraquinone method. Only pickling passivation treatment of the valve was more suitable since hydrogen peroxide had little impact on the application of anthraquinone process in hydrogen peroxide production.

Key words: nitriding process, hydrogen peroxide, austenitic stainless steel, optimization, manufacture, attrition

摘要：

目前国内阀门硬化通常采用渗氮处理，渗氮工艺具有增强阀门使用寿命，提高阀门轴套耐磨性等优点。但采用渗氮工艺处理之后，继续进行酸洗钝化处理后的阀门在蒽醌法生产双氧水工艺中的应用研究较少。为了增加这一方向的研究，论文介绍了对阀杆和轴套表面进行渗氮处理的几种方法，如离子渗氮、射频渗氮、微波渗氮、离子注入和离子湮没注入的方法增加阀杆和轴套的使用寿命和耐磨性。通过对奥氏体不锈钢三偏心异径蝶阀阀杆轴套进行渗氮处理后整体酸洗，酸洗后拆检并采用双氧水进行浸泡，对不同浸泡时间的双氧水进行浓度、稳定度和铁离子的测定，根据实验结果得出渗氮工艺处理过的阀门经过酸洗后，表面会含有大量铁离子，这些铁离子的存在会导致双氧水分解，降低双氧水的浓度和稳定度，因此不适合在蒽醌法生产双氧水中应用。而仅进行酸洗钝化处理的阀门，对于双氧水影响较小，在蒽醌法生产双氧水中应用较为合适。

关键词: 渗氮工艺, 双氧水, 阀门, 优化, 制造, 磨损