NSK轴承安装后，引起轴承旋转困难的原因
Reasons for difficulty in bearing rotation after installation of NSK bearing
NSK轴承安装后，用手转动NSK轴承外圈或轴时，感到转动不灵活，主要原因有以下几个：
After installation of NSK bearings, when the outer ring or shaft of NSK bearings is rotated by hand, the rotation is not flexible. The main reasons are as follows:
1)、氧化铁皮、灰尘等污物等进入NSK轴承，产生垫压和磨削作用；
1) oxide scales, dust and other contaminants enter NSK bearings, resulting in pad pressure and grinding.
2)、水分、酸、碱等腐蚀性介质进人NSK轴承，使NSK轴承产生锈蚀；
2), water, acid, alkali and other corrosive medium into the NSK bearing, so that the NSK bearing rust.
3)、NSK轴承游隙过小，或NSK轴承工作时因温升使内圈膨胀过大；
3), NSK bearing clearance is too small, or NSK bearing work due to temperature rise to expand the inner ring too large;
4)、润滑剂不足、过多或已经干透；
4), insufficient lubricant, too much or dry.
5)、轴颈、轴肩、NSK轴承座的制造精度过低或使用中变形；
5) the manufacturing accuracy of axle neck, shaft shoulder and NSK bearing block is too low or the deformation is in use.
6)、安装密封不正确，如密封太紧或密封件与相关零件发生摩擦；
6) the installation seal is not correct, such as too tight seal or friction between the sealing parts and the relevant parts.
7)、保持架变形；
7), cage deformation;
8)、对加预载荷的NSK轴承，轴向预载荷太大。
8) the axial preload is too large for the NSK bearing with preload.
NSK轴承在运转的过程或是高强度运转环境过程中，必然有过热的现象出现。所以为了防热现象而导致NSK轴承的损坏，我们就不得采取相应的措施了。
NSK bearing must be overheated during operation or high intensity running environment. Therefore, in order to prevent thermal damage caused by NSK bearing, we can not take corresponding measures.
(1)严格控制lcrl8Ni9]ri不锈钢箱体、法兰件的锻造加热温度及加热保温时间，防止工件出现过热使工件产生晶粒粗大缺陷。
(1) Strictly control the forging heating temperature and heating time of LCrl8Ni9]ri stainless steel box and flange to prevent overheating of the workpiece and coarse grain defects of the workpiece.
(2)NSK轴承工件热处理固溶处理温度不宜过高，保温时间不宜太长，加热温度应不高于1150"C，保温时间以1一l_5min／mm计算为宜。
(2) The solid solution treatment temperature of NSK bearing workpiece should not be too high, the holding time should not be too long, the heating temperature should not be higher than 1150 "C, and the holding time should be calculated at 1-l_5 min/mm.
(3)工件锻压生产中，如锻造比过小，终锻温度偏高，也易出现粗晶组织缺陷，应使工件锻造比合适、充分，终锻温度适中。
(3) If the forging ratio of the workpiece is too small, the final forging temperature is too high, and the coarse grain structure defect is easy to appear, the forging ratio of the workpiece should be appropriate and sufficient, and the final forging temperature should be moderate.
(4)对发生过热组织的粗大工件，可采用改锻细化晶粒方法消除缺陷，防止工件在冷变形时出现橘皮状表面缺陷，改善工件的表面质量。
(4) For the coarse workpiece with superheated structure, the method of refining grain by forging can be used to eliminate the defects, prevent the orange peel-like surface defects of the workpiece during cold deformation, and improve the surface quality of the workpiece.