Cross-sections 

A cross-section is an image of a figure obtained by a conditional section of an object by a cutting plane. The cross-section depicts only what is in the cutting plane.

Sections are divided into:

Removable (Figure 3.3.1.);

Superimposed (Figure 3.3.2; Figure 3.3.3.);

Placed in a gap (Figure 3.3.4; Figure 3.3.5.);

Rotated around the trace of the cutting plane (Figure 3.3.6.).

Figure 3.3.1. External section

Figure 3.3.2. Superimposed cross section

If the superimposed section has an axis of symmetry, it can be placed without a designation (Figure 3.3.2).

If the superimposed section does not have an axis of symmetry, it must be placed with a designation (Figure 3.3.3).

Figure 3.3

Sections can be placed in the part break without designation if they have an axis of symmetry (Figure 3.3.4.).

Figure 3.3.4 Section in the rupture of the part

If the cross-section does not have an axis of symmetry, it must be marked (Figure 3.3.5.).

Figure 3.3.5. Section in the rupture of the part

The section may be placed on the extended trace of the secant plane (Figure 3.3.6.). If the section has an axis of symmetry, it is not marked. If the section does not have an axis of symmetry, it must be marked.

Figure 3.3.6. Section placed on the extended trace of the secant plane