This paper studied the precision variation of fine shafting under the low temperature environment in detail from the aspects of material science and assembly clearance, concluded valid method to guarantee the precision of shafting under the low temperature environment.

In view of the current difficulties for measuring and valuating the assembly clearances between car door and car side , the real measurement data of car door and car side have been fitted with the aid of virtual computer assembly technique.

Aiming at laggard and low automatization degree of clearance measure method on axial assembly clearance between half shaft assembly and rear axle housing in automotive rear axle assembly,a new type clearanceometer was developed.

Purpose To find out the reasons of hinder and catch wisdom tooth that unexpectedly entered surrounding tissue during pull out surgery and to probe the treatment and prevent precautionary ways.