To improve the performance of the sheet metal, usually by heat treatment process, through the different annealing, tempering and quenching, change the plate inside the atomic distribution, in the forging and stamping process, cold processing, thereby improving the performance of the sheet metal. The flange is usually the most widely used to start from here, to improve the metal performance of flange by different processing.
First of all, to understand the performance of flange. The flange workpiece exposed to air, oxidation often occurs in stainless steel flange. Decarburization (i.e. the carbon content of steel parts surface, the lower) after heat treatment of parts surface properties have very adverse effects. The flange metal should normally be controlled atmosphere or protective atmosphere. Melting salt and vacuum heating, can also be used to paint or packaging methods to protect the heating.
And then through the heat treatment process, generally including heating, heat preservation, cooling three processes, heating and cooling of the two processes. The general annealing cooling speed, normalizing cooling speed, quenching speed. But also because different types of steel have different requirements, such as empty steel can be used as the cooling rate of normalizing quenching. Flange these processes are connected with each other, can not be interrupted.
Finally, the importance of the heat treatment process of the flange is emphasized. The selection and control of heating temperature are the main problems to ensure the quality of heat treatment. The heating temperature is processing of metal materials and heat treatment purposes vary, but generally are heated to above the phase transition temperature for high temperature structure. Special steel flange heating is one of the important processes of the heat treatment. A lot of the flange metal heat treatment method, the first is the use of charcoal and coal as a heat source, then application of liquid and gas fuel.
In addition, the flange can be applied at high temperature and high pressure, high corrosion and other harsh environment. Change the performance of metal heat treatment on the flange so clearly every time, find out the most suitable flange.
Source: Zhejiang Yaang Pipe Industry Co., Limited (www.yaang.com)