Ball mill main bearing bush burning, red star expert "wonderful hand rejuvenation"
ball mill main bearing bush burning, red star expert "wonderful hand rejuvenation"
China Construction machinery information
ball mill main shaft bush burning is a very serious equipment failure, and its response methods are different according to the degree of burning. Now let's talk about how red star expert can make a wonderful hand rejuvenation in the face of different degrees of main bearing bush burning
I. slight Bush burning
mild Bush burning refers to the situation that the time of Bush burning is short, the degree of bush surface injury is small, only local wear or high points appear, the knowledge worn and brought out is in sheet Babbitt alloy, and the clearance of the Bush mouth at the oil inlet is not blocked. According to the traditional treatment method, it needs top grinding, taking tiles, grinding and scraping, which is both time-consuming and laborious. Experts give a new treatment method
auxiliary transmission slow rotation mill, increase the ventilation of the mill and the oil spray at the burning pad, on the one hand, make the bearing pad and hollow shaft cool down quickly, on the other hand, during the slow rotation process, scrape off the pasteurized alloy adhered to or sintered on the surface of the hollow shaft, and polish the hollow shaft with an oilstone. After the temperature of the hollow shaft is normal, stop grinding, lift out the bearing cover, clean the Babbitt alloy chips at the oil inlet and outlet of the shoe outlet (mainly to clean the clearance between the shoe outlet), clean the oil return filter and oil inlet filter of the thin oil station, and replace the lubricating oil when the oil is dirty. Then start the mill according to the normal production, reduce the feeding amount, and increase the oil pouring amount at the Bush burning place, so that the high point produced by the bush surface can be ground since the first half of this year during the operation of the mill
in addition, during operation, it should be noted that the temperature of the hollow shaft surface should not exceed 75 ℃. When the temperature is high, stop the mill, rotate the mill slowly for cooling, and restart the mill when the temperature of the hollow shaft surface drops to 30 ℃. After several times of running in, the high point can be removed and the temperature of the hollow shaft can reach the normal range
II. Heavy Bush burning
heavy Bush burning means that the Bush burning lasts for a long time, the degree of Bush burning is serious, the Babbitt alloy is brought out in a large amount, the Bush mouth at the oil inlet is seriously blocked, the hollow shaft is grooved and the whole Bush liner can no longer be used
each heavy Bush burning, at least 0.4 ~ 0.7mm Babbitt alloy will be lost, and the service life of main bearing bush will be shortened by 3 ~ 5 years. At the same time, Babbitt alloy will soften at high temperature and be extruded under the pressure of hollow shaft, which will eventually lead to the scrapping of Babbitt alloy layer of circular arc synchronous gear
when dealing with heavy Bush burning, the ball forging in the mill must be poured out, the Bush must be removed by top grinding, and the bearing bush must be scraped again. The maintenance time is long
the traditional scraping method is 25mm × The 25mm contact point shall be no less than 2 ~ 3 points, and the contact angle shall be 60 ° ~ 90 °. The new tile scraping method is more convenient and time-saving
reverse the slope of about 30mm on both sides of the width direction of the bearing bush. Do not scratch within 30 ° of the contact angle, and polish the back with sandpaper. Properly increase the clearance of the bearing opening at the oil inlet, grind and scrape the spherical surface of the bearing with sandpaper around, and do not grind and scrape in the middle, etc. After four times of research and matching with the hollow shaft, the specific technical bottlenecks that will be touched are put into the bearing base and all ball forging test. During the test run, the maximum temperature of the hollow shaft is 43 ℃, and most of the temperature is 38 ℃. When the operation is normal, the maximum temperature of the hollow shaft is 28 ℃, and the local temperature is 43 ℃
according to the above methods, many ball mills with Bush burning failure have been saved. Red Star machine also reminds you that in case of problems, you should learn to analyze the causes and find the right methods, so as to achieve twice the result with half the effort