1. Automatic Rolling Technology
1.1 Technical requirements for rolling
For hot rolling, the main technical requirements are as follows:
One is the heating temperature. The heating temperature will affect the ductility and shape retention time of the steel. If the heating temperature is too high and the steel melts too much, it will be very difficult to shape the steel. Not only is it difficult to shape, but the cooling time will also be prolonged and slowed down. Rolling rate. If the heating temperature is too low, the steel is not easy to melt, and it is difficult to process and shape it in the next step. Especially for hot-rolled thick plates, the thickness of the thick plate itself will affect its cooling time. Controlling the appropriate heating temperature can relatively reduce its cooling time and speed up the hot rolling rate while ensuring its thickness.
The second is the amount of pressure. The size of the pressure will affect the thickness of the steel plate. If the pressure is high, the steel plate will be thinner. If the pressure is small, the steel plate will be thicker. When rolling the steel, the pressure should be carefully controlled to obtain a steel plate with a suitable thickness. Just like rolling dumpling skins, the thickness of the dumpling skins is continuously changed under the pressure of the rolling pin until the appropriate size and thickness. The standard for dumplings. Therefore, if the pressure is too high during rolling, the steel plate may be crushed. If the pressure is too small, the thickness of the extruded steel plate may not meet the standard.
Third, rolling standards. Different customers have different requirements for the size, thickness, and even shape of the steel plate. When rolling steel, pay attention to the size setting and meet the customer’s standards. If the thickness or length of the steel plate does not meet the requirements of the user, it must be carried out. Rebuilding is not only a waste of time but also a waste of materials.
For cold rolling, the main technical requirements are as follows:
First, remove the oxide film. Before cold-rolling the steel, the oxide film must be removed first, otherwise, the next step of production cannot be carried out. The items used to remove the oxide film must be carefully selected to ensure normal production. The commonly used items are It is hydrochloric acid, because the appropriate concentration of hydrochloric acid and its unique properties can ensure that it will not produce excess compounds while removing the oxide film, affecting product quality or causing excessive corrosion to steel, causing environmental impact.
Second, rolling thin strips. No matter what the finished product required by the customer is, the thickness of the steel strip must be modified first. If the customer wants only the ordinary cold-rolled sheet, then after the steel plate is thinned, it will be carried out according to the shape required by the customer. Just produce. If the customer wants to coat the coated sheet, another process is needed to coat the steel sheet before the next production operation.
Third, is the coating process. The characteristics of the products are different depending on the metal to be plated. If different pigments are used for coating, plated steel sheets with different colors can also be obtained. Depending on the use of the product, different coating processes can be used. For example, in the production of cans, aluminized sheets can be used; if they are to be used for power generation, silicon steel sheets can be used.
1.2 Automatic steel rolling technology
At present, automatic steel rolling technology is widely used in my country’s steel rolling production, and my country’s demand for various steel products is very large. In construction, a large number of steel bars and steel plates are needed to make the base as a frame; in society, infrastructure and playgrounds are constructed with steel; in the family, many household appliances made of metal materials are mostly made of steel. to make. The large demand places high demands on the production of steel, and the speed of production of steel must be able to meet the speed of its use.
In the past, my country’s steel rolling technology could not meet the needs of users, and a large amount of steel had to be imported from abroad. One of the reasons was that the quantity was insufficient and the demand for steel was large. However, my country’s steel rolling production speed was slow and could not meet a large number of user needs. ; Another reason is the lack of types. my country’s demand for rolled steel products is not just some basic steel plates. Various types of rolled steel products are needed in various aspects such as electrical appliances and food. However, my country did not have the corresponding technical conditions at that time. These products have to be imported from abroad. In this way, not only the cost is high, but also the development will be limited, but at present, my country has mastered enough steel rolling technology to meet various production requirements, and the automatic steel rolling technology has surpassed other countries and is far ahead in the world. Whether it is the quantity or the type, it can be used by the people of our country.
1.3 The important role of automatic steel rolling technology in steel rolling production
First of all, to ensure the quality of rolled steel. The automatic steel rolling technology has uniform standards and specifications in the production of products. The rolled steel products produced by it will have smaller errors and can ensure the size and quality of the rolled steel. For example, a customer needs 100 steel plates with a length of 1m, a width of 0.5m, and a thickness of 3cm. Through the automatic steel rolling technology, the size of each steel plate can be guaranteed to be “1m in length, 0.5m in width and 3cm in thickness”. , even if there is an error, the error range can be controlled to a level that is invisible to the naked eye.
Second, ensure the production rate. Automatic steel rolling can produce more products in less time, increasing the production rate.
In addition, automatic steel rolling technology can also ensure safety problems in steel rolling production and reduce safety hazards. Because in the steel rolling production process, it is necessary to use ultra-high temperatures to melt the steel, and there are a large number of materials with very exaggerated volume and quality. A little carelessness will pose a threat to personal safety, and automatic steel rolling technology is largely Some manual operations are avoided, so that the staff can carry out the operation of rolling steel production in a safe area and prevent direct contact with dangerous factors.
2 Development and application of automatic steel rolling technology in steel rolling production
2.1 Process comparison between automatic control and manual operation
First of all, automatic control requires less labor, and the jobs that require labor are only program setting, machine maintenance, and production supervision. These positions only need a few people to be competent, which can save a lot of labor costs. The manual operation requires a lot of labor, and every procedure of each steel plate needs to be performed manually, which is not only costly but also inefficient.
Secondly, the products produced by automatic control will be more standard than those produced by manual operation. Whether it is product quality or product size, it is a level that cannot be achieved by manual operation. In automatic control, the machine is used for rolling steel production, and the material ratio and size of the products produced are fixed, which can produce more “exactly the same” products, which cannot be achieved by the products produced by manual operation.
Also, automatic control is more productive than manual operation. If the same 10,000 steel plates are required to be produced, the automatic control may only take 1 hour, but the manual operation may take 1 week, 1 month, or even longer. Automatic control has many advantages that cannot be surpassed by manual operation, but the manual operation also has incomparable characteristics to automatic control. The products produced by automatic production are mainly used in the production requirements of large quantities and fixed styles. If the number of rolled steel products to be produced is small and the styles are many, then automatic control is not as good as manual operation, because the manual operation can meet more style requirements of customers. . If a customer asks to produce a sunflower-style rolled steel plate, using automatic control to produce a limited amount of fuss, the value of the product is not as good as the cost of running the machine during the production process.
2.2 Process control system and distribution of basic automation functions
In the production process of automatic steel rolling, although it can be automated, the premise of automation is the perfect setting of the process control system, and a rigorous production process must be established to ensure normal production. When setting up the process control system, first of all, it is necessary to ensure the correct production sequence setting; secondly, to ensure the regular inspection of the system, so as to find out the possible problems in time and solve them; finally, to upgrade the system and continuously improve the system. In addition, paying attention to the distribution of basic automation functions, cannot be taken lightly because of its automation characteristics.
The development of automatic steel rolling technology can increase the speed of steel rolling production and ensure product quality, which is not only of great significance to steel rolling production, but also has a very important impact on other industries that use steel for construction.