1. What preparations should be made before rolling? – Rolling mill rolls
To produce each product, you should start preparing for the roll change. In order to ensure the normal rolling production, the roll position, the main and auxiliary parts of the rolling mill and related equipment must be inspected before rolling. The structure of the rolling mill is different, and the items to be inspected are also different. Generally, the items that must be checked are:
1) Roller Consider the position of the roll after the roll jump;
2) Rolling mill components Check various rolling mill components according to the technical regulations;
3) Rolling mill accessories Check the rolling mill accessories according to technical specifications and practical experience;
4) Auxiliary equipment Make sure that the auxiliary equipment is correct.
2. What are the common types of racks? – Rolling mill rolls
Open, closed and semi-closed.
The open frame consists of a frame base and an upper beam. The advantages are simple manufacture, convenient loading and unloading, and roll change. The disadvantage is that the strength and rigidity are low, and the roll value of the roll is large.
Due to the wide variety of steel profiles, steel mills, especially small and medium-sized mills, mostly use open mills.
The closed frame is made of a monolithic casting, which has the advantages of large strength and rigidity, large rolling pressure or strict requirements on the size of the rolled piece, such as the rolling mill, the steel mill, and the cold rolling. Machine and so on.
The semi-closed rack is slanted to the frame cover. The utility model has the advantages of both the open type and the closed type, which is convenient for loading and unloading, changing the roll, easy to manufacture and large rigidity. Generally, large and medium-sized steel rolling mills use this type of frame.
In addition to the above several types, there is also a non-brand rolling mill, which has the advantages of light weight, good rigidity, high rolling precision and convenient adjustment operation.
3. What technical requirements should the Rolling mill rolls meet?
Whether hot or cold, rolls are a direct tool for achieving metal deformation during rolling. Therefore, the quality of the rolls is strict. Its main quality requirements are strength, hardness and certain heat resistance. Roll strength is the most basic quality index. While meeting the strength requirements, it must also have a certain impact toughness. In order to have sufficient strength of the rolls, it is mainly considered from selecting the material of the rolls and determining the reasonable roll structure and size. Whether the strength is sufficient or not can be determined according to the roll strength calculation. Hardness generally refers to the hardness of the working surface of the roll and is also the main indicator of the roll, which determines the wear resistance of the roll. To a certain extent it determines the service life of the rolls. Strength requirements can be met by material selection and some heat treatment of the roll surface. In addition, when the roll is operated under hot rolling conditions, it should also have a certain degree of wear resistance to protect product accuracy.