Surface Strengthening Treatment of Rolling Mill Roll
Rolling mill rolls are key components to ensure the normal operation of the rolling mill. The rolling mill roll is mainly composed of roll body, roll neck and rib. The roll body is the main load-bearing part of the rolling mill roll and its size is the basis of the size of the rolling mill. The roll neck is the part that transmits the power between the roll body and the rolling mill stand, and its structure must have sufficient strength and rigidity. The rib is the shape of the roll neck and the roll body. Part. Rolls are subject to repeated impact and powerful alternating loading during rolling. Since the surface hardness of the roll is insufficient, it will cause premature failure of the roll, resulting in scrapping, which impacts the production cycle of the enterprise and increases its production costs. Therefore, surface strengthening treatment of the rolling mill roll is necessary.
There are many surface strengthening treatment methods for rolling mill rolls, including quenching and tempering, surface chemical heat treatment, ultra-low temperature heat treatment, roller overlay heat treatment, roller retrieval heat treatment, etc. Quenching and tempering is a general heat treatment method that uses quenching and tempering to obtain the required performance. It has the advantages of low cost, short cycle and easy control. However, due to the high quenching and tempering temperature, the structure of the roll is coarse and the service life is short. The surface chemical heat treatment of the rolling mill roll is characterized by low temperature and fast speed, which can improve the surface chemical composition, reduce the decarburization depth and reduce the surface oxidation rate. Ultra-low temperature heat treatment is a new type of heat treatment process. The main feature is the low temperature and the unique cooling speed. It can form a unique high-hardness nano-layer on the roll surface, so as to improve the wear resistance and toughness of the roll surface. The roller overlay heat treatment is to use welding technology to deposit a layer of special alloy hard surfacing material on the roller surface to form a wear-resistant surface layer. The roller surfacing heat treatment is a kind of improvement of roller surfacing heat treatment method, which is based on the roller overlay heat treatment to carry out the repair technology of the wear-resistant layer.
In summary, in order to improve the wear resistance of the rolling mill roll and extend its service life, the surface strengthening treatment of the rolling mill roll is indispensable. According to different conditions, different surface strengthening treatment methods must be selected. Only by ensuring the smooth operation of the rolling mill and reducing the cost of enterprises can the production output and economic efficiency be improved.
