In terms of high-speed adaptability and running accuracy, the performance of super-precision bearings is undoubtedly changing with each passing day. However, unless the accuracy of the mating parts can be synchronized with the bearing, it is impossible to give full play to the performance of the bearing. The size, shape and position tolerances of ultra-precision bearings listed in the table below have passed the test of various applications. These values u200bu200bhelp to select the fit faster and better, ensuring reliability and interchangeability. The roughness of the bearing mounting surface must meet the requirements of the average roughness Ra to ensure normal tightness changes. The general application rules of rolling bearing technology are: The direction and influence of load. The choice of inner ring or outer ring. Pay attention to the change of fit tightness caused by temperature rise and centrifugal force. Shaft tolerance symbol d u003d nominal diameter of the shaft or bearing bore d'u003d diameter of the small end of the tapered shaft (u003d d + tolerance in the table) d1' u003d diameter of the large end of the tapered shaft d1' u003d d'+ 1/12 · LL u003d cone Shaft length L u003d 0.95 B (bearing width) t1 u003d cylindricity (DIN ISO 1101) t2 u003d roundness (DIN ISO 1101) t3 u003d flatness (DIN ISO 1101) t4 u003d axial runout tolerance (DIN ISO 1101) t5 u003d Concentricity (DIN ISO 1101) ATD u003d Cone tolerance (DIN 7178) Ra u003d Average surface roughness (DIN 4768). Bearing seat tolerance symbol D u003d Nominal bore diameter of the bearing seat t1 u003d Cylindricity (DIN ISO 1101) t3 u003d Flatness (DIN ISO 1101) t4 u003d Axial run-out tolerance (DIN ISO 1101) t5 u003d Coaxiality (DIN ISO 1101) Ra u003d Average surface roughness (DIN 4768) Spacer tolerance symbol d2 u003d Spacer nominal diameter D2 u003d Spacer nominal outer ring diameter t1 u003d Cylindricity (DIN ISO 1101) t4 u003d Axial runout tolerance (DIN ISO 1101) t6 u003d Parallel Degree (DIN ISO 1101) t7 u003d radial runout tolerance (DIN ISO 1101) Ra u003d average surface roughness (DIN 4768).