produce

Influence

Divided according to geometric structure characteristics

Divided by state of existence

Divided according to position in geometric tolerances

Divided according to functional relationship

Textbook P73, Table 3-1

Shape tolerance

Current Tolerance Zone

The national standard stipulates that the minimum condition (minimum area fitting criterion) is the basic principle for evaluating shape errors.

The datum plays a role in determining the direction or positioning of the measured element in the direction and position runout tolerance. It is also an important basis for determining the azimuth position and the direction of the runout tolerance zone.

Classification

Directional tolerance can be defined as the total amount of change allowed in the direction of the associated elements relative to the datum. Directional tolerance includes parallelism. This system inclination has directional requirements for line contours and surface contours.

The directional tolerance zone has a certain direction relative to the datum and has the function of comprehensively controlling the direction error and shape error of the measured element. For details, see Table 3-3 on page P79 of the textbook.

Position tolerance refers to the total amount of variation allowed in the position of the associated elements relative to the datum. Position tolerance includes six types: concentricity, coaxiality, symmetry, position, line profile and surface profile with position requirements.

The position tolerance zone has a definite position relative to the datum and has the function of comprehensively controlling the position, direction and shape of the measured element. For details, see Table 3-4 on P84 of the textbook

Circular runout tolerance

Full runout tolerance

The runout tolerance has the function of comprehensively controlling the position, direction and shape of the extracted elements being measured. For example, the axial full runout tolerance can simultaneously control the perpendicularity of the end face to the reference axis and its flatness error; the radial full runout tolerance can control the coaxiality and cylindricity errors.

Extract the local dimensions of the component elements (referred to as the local dimensions of the extracted elements)

The action size of a single element (referred to as the action size)

The effect size of associated elements (referred to as the associated effect size)

Maximum entity status and maximum entity size

Minimum entity status and minimum entity size

Maximum entity effect state and maximum entity effect size

Minimum entity effect state and minimum entity effect size

principle of independence

related requirements