Steel rolling machinery and equipment is one of the important equipment in the current industrial development. Its operation effect and efficiency can be said to be directly related to its performance. In order to make the steel rolling machinery and equipment operate normally, it is also very critical to improve the operation effect of the bearing bush of the steel rolling machinery and equipment. Combined with the specific situation of the bearing bush of steel rolling machinery equipment, this study analyzes the problems and maintenance points of the bearing bush maintenance of steel rolling machinery equipment, in order to improve the operation effect of steel rolling machinery equipment.

In the actual operation process, steel rolling machinery has the characteristics of high bearing weight, low running speed and high impact compliance. At the same time, the common influence of factors such as the operating environment of steel rolling machinery makes the surrounding environment of bearing bush components of steel rolling machinery very bad. This also makes its operation efficiency and performance unable to be brought into full play to a large extent, which has a great impact on the normal use of rolling machinery. Therefore, strengthening the maintenance of bearing shells of rolling machinery equipment is an important method to improve the safe and stable operation of rolling machinery equipment, and it is also the key to ensure the timeliness and stability of bearing shells. This paper briefly summarizes the maintenance points of bearing bush of steel rolling machinery equipment.

1. Analysis of common problems in the maintenance of bearing bush equipment of steel rolling machinery

1.1 common problems of bearing bush pouring

When pouring bearing shells, the most common problems mainly include: uneven handling of tin hanging operation; The preparation for pouring is not in place; During the cleaning of bearing liner, due to incomplete or incomplete cleaning and other factors, it is very easy to cause the bonding of Babbitt alloy friction reducing layer after bearing liner pouring to be not tight enough. In addition, it can also lead to the situation of bearing liner shell of bearing liner, which may affect the operation of steel rolling machinery.

1.2 common problems of bearing bush scraping

During the scraping and grinding of the bearing bush, there are quality problems such as scratches on the contact surface of the bearing bush and uneven distribution of contact points, which are mainly caused by the uneven stress on the bearing bush. As we all know, the deformation of the bearing bush mouth is mainly due to the toughness of the raw materials used in the steel rolling machinery and equipment. Under the influence of this deformation, it will produce an inward shrinkage force, which will lead to the uneven distribution of the contact surface between the bearing bush and the generator shaft. When the rolling machine is running, the uneven stress distribution will lead to the bearing bush heating, and this heating symptom also shows an uneven state. Therefore, under the influence of the temperature difference at the contact point, the quality of the bearing bush will eventually be affected.

1.3 common problems of bearing bush alloy surface quality

According to long-term practice, the alloy surface of bearing bush of a single steel rolling machine often shows the quality problem of slag inclusion or porosity, and the normal operation of the whole bearing device can be affected. The most critical factor that causes this problem is the chemical composition of the bearing bush alloy. Under the action of the chemical composition, the filling conditions and temperature of the casting mold of the bearing bush will change, which has a great impact on the quality of the bearing bush.

2. Analysis of maintenance points of bearing bush of steel rolling machinery equipment

2.1 bearing bush pouring and maintenance

In order to avoid the problem of weak connection between Babbitt alloy and bearing liner shell during bearing bush pouring, the bearing liner shall be thoroughly cleaned in the process of maintenance, so as to prepare for maintenance. Generally, alkaline water is the first choice when cleaning it, which can eliminate various forms of oil stains left in the bearing liner. After the first cleaning, it is necessary to dry the residual water in the bearing liner, and then use ZnCl2 saturated solution to clean the bearing liner again. The most important thing in cleaning is to ensure the effective connection between the bearing liner and tin during the casting of the bearing bush of steel rolling machinery, so as to make it more dense. In addition, during the maintenance, pay attention to the effective control of the pouring rate. At the same time, pay attention to the uniform way during the pouring process, so as to avoid the quality problems caused by the lack of form when the bearing is hanging tin.

2.2 bearing bush scraping and maintenance

In order to realize the long-term and efficient operation of bearing shells of steel rolling machinery and equipment, it is very important to improve the lubrication characteristics between bearing shells during operation. However, from the perspective of bearing pad scraping, the reasonable use of scraping can effectively improve its adaptive stress area and uniformity of load-bearing, that is to say, an invisible high-grade oil film is installed on the outside of the bearing pad. For this reason, this scraping and grinding is the preferred method for maintenance. The scraping contact angle in the bearing area of the bearing bush must be controlled at about 80 °, and the scraping operation needs to be carried out by means of the grinding point towards the middle. In general, the basic size of bearing pad grinding points should be controlled within 25mm × Above 25mm. The most critical point in this link is that during scraping and grinding, the direction of the next step of the scraper should maintain a cross shape according to the direction of the last step of the scraper, and always maintain this way of summarizing interactivity, and based on this, improve the flatness of the subsequent burr repair of the scraper.

2.3 maintenance of bearing bush alloy surface defects

In order to avoid the influence on the alloy surface of bearing bush caused by the quality problems of air holes and gas slag, which brings difficulty to the pouring operation of bearing bush, it is necessary to properly and effectively control it in combination with the pouring temperature in the process of maintenance. Generally, when pouring, the temperature is too high, which can make the bearing bush alloy surface have very superior liquidity characteristics. Due to the influence of this factor, it will also show a good filling effect when pouring the bearing bush. In the past, when we were overhauling the steel rolling machinery, we were shocked that the slag inclusion quality of ICBC was affected. At the same time, it is also necessary to pay attention that the pouring temperature should not be too high, so as to avoid defects in the quality of surface pores due to oxidation reaction when the air intake of bearing bush continues to increase. In short, when pouring the bearing bush and selecting the temperature, attention should be paid to ensure the filling capacity of the liquid bearing bush alloy, so that it can play the best effect, so as to avoid the appearance of surface defects and quality problems. Generally, during pouring, the best temperature is 230-250 ℃, and the bearing bush and shaft core are effectively preheated at 150 ℃ before pouring.

3. Conclusion

To sum up, we should start with the specific work of bearing bush maintenance of steel rolling machinery equipment, and form the quality assurance system and key steps of bearing bush maintenance of steel rolling machinery equipment from the application of key maintenance links and key technologies, so as to truly put the bearing bush maintenance of steel rolling machinery equipment into the track of technology, management and standardization.