Practice shows that valves seal often only a few times for the opening and closing, because sealing abrasion caused by the leak. Minor scratches need open and repair, abrasions serious were scrapped damage, such consequences will not only increase the company's manufacturing costs, but also affect the performance of the globe valve. In order to solve such problems of the valve sealing material has been improved.
Change on the sealing material. Cone on the stem seal surfacing alloy good anti-abrasion performance, this method has yielded good results, but on the one hand because the good alloy cost is too high, on the other hand, since the stem base material for the 13Cr martensitic stainless steel, weldability is poor, required to preheat before welding, after welding, insulation and welding complex air compressor valve, spring safety valve, inching valve spring. In addition, in order to ensure the dimensional accuracy of the stem, but also increase the roughing process. Comprehensive analysis, in addition to special requirements, the cost of this program is not good.