Stick - bearing production lines rolling mill bearing inner ring damage cause analysis knowledge

Home of guided reading of steel rolling is committed to release can solve actual problem, for the majority of fans and their brothers, provide reference and reference. Thank the rolling in the group of friends communication, thank 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, lubrication grease lubrication. Recent inner ring frequently appear rupture phenomenon, seriously affected the normal production. The steel mill has organized this factory and bearing factory technical personnel at the scene of the 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 a typical, from damage to the bearing surface longitudinal crack, can see there is a clear phenomenon of this kind of damage is there are three reasons for this: 1) Roll diameter than standard tolerance is too much, roller diameter size tolerance is phi 220 p6 ( + 0. 079 + 0. 05) , the roll diameter greater than most surplus tolerance can not exceed 0. 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 interference amount more than 0. 10 mm, inner ring online will appear crack phenomenon. 2) Roll diameter size tolerance is less than the standard 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, will not be able to work rotating is bound to make the diameter of inner ring and roll produces peristalsis, this is also an important cause of the inner ring on crack. 3) Roll diameter surface straightness can not meet the requirements ( Roll diameter surface uneven phenomenon exists) , this kind of phenomenon, in the old roll ( It hasn't reached standards roll) Is widespread. Figure 3 and figure 4 is figure 1 and figure 2 inner ring with roller, image reflects the roll on both sides of the roller diameter. The scene to understand the roll has been used many times, 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 surface straightness measuring roll diameter, roll diameter surface concave and convex visual at 0 degrees. More than 10 mm. Combined with the comprehensive analysis of monitoring data and the concave and convex roller diameter, inner ring appears on the reasons for crack phenomenon for surplus is too small and the surface concave and convex roller diameter can be determined. For detecting the other roll diameter, roll on the site there are a lot of similar conditions. In view of the above conditions, are as follows; 1) New roll in front of the library to build system of sampling inspection, unqualified roll to eliminate 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 requirement for timely replacement of new roll or repair of the roll. 3) Used the roll diameter and focus of straightness measuring roll diameter surface, light gap method. 4) To focus on testing the repaired roller diameter size tolerance and straightness. 5) In order to ensure the interference to the requirements, the bearing inner diameter size tolerance to control in 220 ( 0 to - 0. 030). 。