工程机械产品钢管件的表面处理，国内生产厂家采用较多的方法是酸洗钝化、磷化、发蓝、喷玻璃微珠等。我公司1997年以前，采用的是盐酸除锈、亚硝酸钠钝化工艺，但保证不了涂装前处理的质量。后来，长度小于lin的钢管与接头改用发蓝处理。发蓝工艺即传统的高温发黑工艺，需要消 Construction machinery products, steel pipe surface treatment, the domestic manufacturers adopt more methods are pickling passivation, phosphating, blue, glass beads and so on. Before 1997, our company adopted hydrochloric acid derusting and sodium nitrite passivation process, but it can not guarantee the quality of pretreatment. Later, the length of less than lin pipe and connector to use blue hair treatment. Blue hair process that is the traditional high temperature blackening process, the need to eliminate