“The real stainless steel pipe fittings products should be able to use a hundred years will not rust.” Tao said.
National Steel Products Quality Inspection Centre BARROW have encountered similar problems. Two years ago, the National Steel Products Quality Inspection Center of the laboratory building to reform, to request the construction side, the use of decorative stainless steel pipe fittings need to adopt a true 304 grades (of good quality stainless steel pipe fittings as a model).
“Construction of side clear answer can not buy. Construction is well aware of the nature of our work, so I do not install the fake products, if the owners of other decoration and reconstruction, using up the stainless steel pipe fittings products do not know what stuff the . “Bao Lei said.
At present, Wire edm machine product line consists of 200, 300 series and 400 series. Different standards, contained chromium, nickel, manganese and quantity vary widely, performance also will be very different.
Standard 304stainless steel pipe fittings, chrome and nickel content of 18% and 8%; and 200 series stainless steel pipe fittings, chrome and nickel content was low, added a large percentage of manganese.
Ni is an expensive metal. During World War II, due to a serious shortage of nickel supply, the Germans first developed to replace the part of the manganese nickel stainless steel pipe fittings. 50 years of the 20th century, Americans in-depth study will develop a high manganese instead of nickel-manganese series stainless steel pipe fittings, the 200 series. This series is still 18% chromium and nickel content is slightly reduced.
After the beginning of this century, the Indian markets have J1 and J4 grade stainless steel pipe fittings, this stainless steel pipe fittings replaced with two manganese a nickel, chromium while the proportion fell to 13%, generally contain 13% chromium and 13 % of manganese and nickel content in no.
“This product is stainless steel of very poor.” Tao said. The product into the Chinese market, some Chinese companies to “study.” School out of a result, some enterprises 200 U.S. Department of counterfeit products, the domestic call so-called “200 series”; the same time very good quality fake 304.
“Most people also do not identify them, now with so many people still use the magnet to the screening of stainless steel pipe fittings, not the truth.” Tao said.
In his view, from a corrosion point of view, Aluminum casting might as well not add manganese. The formation of a manganese oxide rust easily. So why some enterprises have to add a stainless steel pipe fittings manganese? Because while reducing the proportion of added chrome manganese, magnet not live on the suction, so use the consumer’s “common sense” to deceive consumers.
View from metal properties, magnetic iron and chromium, and nickel are not magnetic, adding a certain proportion of chromium, the steel would have an anti-corrosive; while adding a certain percentage of nickel would increase the ductility of stainless steel pipe fittings.
Zhang Tao said that the current production of the domestic market of 201 and 202 models of 200 series products are not the United States, but the fake so-called “200 series” really hard to find items.
stainless steel pipe fittings are very popular decoration materials sales. Beijing, a decorative material store told the author, a salesman, “Our stainless steel pipe fittings Decoration Materials products do not contain magnetic, will not rust.”