柴油机燃油系统所使用的柱塞偶件、喷油器偶件以及出油阀偶件,每年都要消耗大量的备用零件,而制造这些柱塞偶件主要采用铬钨锰钢和滚珠轴承钢。据有关单位试验证明,采用经表面渗碳处理,使渗碳层含碳量达3.5%或更高一些的铬钨锰钢所加工的柱塞偶件,其耐磨性能可提高 Plunger couplers, injector couples, and delivery valves used in diesel fuel systems consume significant amounts of spare parts each year, and the chrome-manganese-manganese steels and ball bearing steels used to make these plunger couples are mostly used. According to the unit test proved that the use of surface carburizing treatment, carburizing carbon content of 3.5% or higher chrome tungsten manganese steel machining of the plunger coupling, the wear resistance can be increased