First, the interchangeability of parts
Precision parts processing factory, the machine by long-term production operation, certain parts will inevitably wear, deformation and scrap, replaced with new parts. These parts are called accessories or spare parts. Accessories or spare parts without repair or selection, installed in the machine can be run, known as interchangeability.
In order to achieve interchangeability, when manufacturing parts, the size and geometry of the parts should be made consistent. The so-called consistent, not required to do exactly the same (this is neither economic nor possible), as long as the size of the parts, geometry, etc. control within a permissible range, so that the parts and other parts combined with the same combination of performance on the line. This is allowed range of error, that is, the shape tolerance.
Second, the quality of precision parts processing with processing accuracy to express.
1. Geometric shape accuracy
Geometric shape accuracy refers to the composition of the parts of the surface or axis and other geometric shape of the degree of accuracy, such as whether the line is straight, whether the surface is flat, cylindrical cross-section is round, etc.. Its allowable range of change to "tolerance" to express, the smaller the shape tolerance number, the higher the shape accuracy.
2. Dimensional accuracy
Precision parts processing factory analysis, dimensional accuracy refers to the accuracy of the size of the parts after processing, to "dimensional tolerance" to express. When the size of the part is the same, the higher the precision, the smaller the tolerance figure.
3. Position accuracy
Precision parts processing factory, location accuracy refers to the accuracy of the mutual position between the surfaces of the components, such as whether the two planes are parallel, perpendicular, two axes are coaxial, etc., to "location tolerance" to express.