Small bar consumption line rolling mill bearing inner ring damage reason analysis

Home of guided reading of steel rolling working on publishing articles can handle practical problems, and their brothers, who is a vast, create and reference! In the home of gratitude rolling discussion of each group of friends appreciate WeChat public, 【 Rolling mill bearing 】 Authorized reprint dry article! A hot rolling stick line roughing mill a total of three, rolling machine, a total of four, finishing mill, 8 FC4462192 mill used in bearing, smooth smooth way as the grease. Recent inner ring frequently appear rupture phenomenon, seriously affect the normal consumption of the workshop. The steel plant has repeatedly organization stop factory and bearing factory technical personnel in the field to find bearing damage, the bearing damage pictures as follows; Figure 1 and figure 2 is the same inner ring images of different Angle, this is the damage to the inner ring of compare with the typical one, from the damaged bearing appearance can clear there is a longitudinal crack, damage of this phenomenon is formed by three reason: 1) Roll diameter tolerance too much beyond specification, standard roller diameter size tolerance is phi 220 p6 ( + 0. 079 + 0. 05) , roll diameter greater than most surplus tolerance cannot go beyond zero. 8 mm, bearing inside diameter tolerance in process will ensure the phi 220 ( - 0. 02 - - 0. 03) Within the scope of bearing inside diameter tolerance is the sum of the biggest roll diameter tolerance is zero. 10 mm, if the amount of interference beyond zero. 10 mm, inner ring online using a through crack phenomenon is present. 2) Roll diameter size tolerance is less than the specification tolerance, when the inner ring loaded on the roll diameter does not have enough interference quantity guarantee the inner ring and the roll concentric rotation, can not be concentric rotating is bound to make the diameter of inner ring and roll produces creep, it was also formed inner ring crack one of the most important reason. 3) Roll diameter appearance straightness can not meet the request ( Roll diameter looks uneven phenomenon exists) , this kind of phenomenon, in the old roll ( Haven't reach the scrap specification roll) Is widespread. Figure 3 and figure 4 is figure 1 and figure 2 inner ring USES roll, image reflects the roll on both sides of the roller diameter. The scene to understand the roll has been used repeatedly, the scene of the roller diameter testing data are as follows; Figure 3 test data: phi 220 ( + 0. 04 + 0. 05 - 0. 05) , + 0. 04 is close to the roll side, + 0. - 05 is middle roller diameter tolerance 0. 05 is outside of tolerance. Figure 4 testing data: phi 220 ( + 0. 02 + 0. 03 + 0. 05) , + 0. 02 is close to the roll side, + 0. 03 is middle roller diameter tolerance, + 0. 06 is lateral roll diameter tolerance. By using light gap appearance straightness measuring roll diameter, roll diameter bump is at 0 degrees visual appearance. More than 10 mm. Separated roll diameter comprehensive analysis of testing data and bump degrees, inner ring appears on the cause of the crack phenomenon can certainly for surplus is too small and concave and convex form of roller diameter appearance. For detecting the other roll diameter, roll on the site there are a lot of similar conditions. In view of the above conditions, initiative as follows; 1) New roll in front of the library must set up sampling system, unqualified roll used in warehousing, roll size tolerance according to the national standard phi 220 p6 ( + 0. 079 + 0. 05) The execution. 2) Every time the plane within a new set of roll to outside micrometer is used to inspect the diameter interference tolerance, interference tolerance can not meet the request to change new roll or repair roll in a timely manner. 3) Used the roll diameter and focus of straightness measuring roll diameter appearance, light gap method. 4) To focus on testing the repaired roller diameter size tolerance and straightness. 5) In order to ensure the interference quantity reach request, bearing inside diameter size tolerance to control in 220 ( 0 to - 0. 030). 。