Metal of 304 stainless steel seamless pipe and oxygen in the atmosphere to react, the appearance will form an oxide film. However, the iron oxide formed on a common carbon steel pipe is continuously oxidized, causing the corrosion to continuously expand, and as a result, pores are formed. Such good stainless steel seamless pipes are damaged. We can use galvanized paint or oxidation-resistant metals such as zinc, nickel and chrome to coat the carbon steel. However, as we expected, this maintenance is only a layer of maintenance film, assuming the maintenance layer is damaged, the steel will begin to be eroded. The corrosion resistance of stainless steel depends on chromium. Chromium is part of the steel composition. When chromium is combined with steel, the type of oxide in the surface changes to a surface oxide similar to pure chromium metal. This tightly adhering chromium-rich oxide maintains the appearance and avoids further oxidation.
Heat treatment process includes heating, insulation, cooling, etc., this is done in order to reduce the deformation of the metal forming process due to hardening and other shortcomings, the processing of deformed pipe back to before processing, so that performance is improved.
Now the most common heat treatment tools, including electric furnace and refire furnace; commonly seen control method is automatic temperature control mode.
Different 304 stainless steel seamless pipe fittings require different heat treatment, and not all the deformation of the tools have to be heat treatment, usually low-carbon steel pipe fittings, the final temperature of not less than 723 ℃, then you can not heat treatment, if below this temperature or above 1000 degrees celsius heat treatment should be carried out.
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