Precision machining precision parts include
Dimensional accuracy
Refers to the actual size of the machined part and the tolerance of the part size.
Shape accuracy
Refers to the machined parts of the surface of the actual geometry and the ideal geometry to meet the degree.
Position accuracy
Refers to the difference between the accuracy of the actual position and the theoretical position on drawing of the parts after processing.
Interrelationship
Usually in the design of machine parts and parts machining accuracy, should pay attention to the shape error control in the position tolerance, the position error should be less than the size tolerance. This is to say that the precision parts or parts important surface, the shape accuracy requirements should be higher than the position accuracy requirements, the position accuracy requirements should be higher than the dimensional accuracy requirements.
Parts processing size
Whether the edge is chamfering or not
Roughness (in the past called finish) is the main part processing index