Cuts 

A section is an image of an object conditionally cut by one or more planes. A section shows what is in and beyond the cutting plane.

Horizontal sections (Figure 3.2.1.) – the cutting plane is parallel to the horizontal projection plane;

Vertical sections (Figure 3.2.2; Figure 3.2.3.) – the cutting plane is perpendicular to the horizontal projection plane;

Inclined (Figure 3.2.4.) – the cutting plane is placed at an angle to the projection plane.

Figure 3.2.1. Horizontal section

Figure 3.2.2. Frontal section

Figure 3.2.3. Profile section

Figure 3.2.4. Inclined section

Complex sections are divided into:

1. Stepped (Figure 3.2.5.) – formed by several planes parallel to each other;

2. Broken (Figure 3.2.6.) – when the cutting planes intersect.

Figure 3.2.5. Stepped section

Figure 3.2.6. Broken section

A broken section is depicted as if the inclined plane is rotated to align it into one plane. When rotating the cutting plane, the elements of the part located behind it should not be displaced by the angle of rotation. In other words, they are projected as in ordinary simple sections (Figure 2.7.).

Figure 3.2.7. Broken section

GOST 2.305-68 establishes conventions and simplifications when performing sections. If the section plane coincides with the plane of symmetry of the part, and its image is in a projection relationship, then the position of the section plane is not indicated and the section is not labeled (Figure 3.2.9).

Figure 3.2.9

If the part is symmetrical, then instead of a full section, half of the view should be combined with half of the section (Figure 3.2.10). The axis of symmetry serves as the boundary between them. As a rule, the section is placed to the right or below the image axis.

Figure 3.2.10

The axis of symmetry cannot serve as the boundary between the view and the section if there is an internal or external edge at the point of symmetry of the part (Figure 3.2.11). In this case, the boundary is indicated by a solid wavy line.

Figure 3.2.11.

If the cutting plane passes along a thin wall (stiffening rib, thin partition, etc.), then the wall cut by this plane is shown unshaded and limited by a visible contour line (Figure 3.2.12.). The cross-section of a thin wall is depicted shaded.

Figure 3.2.12.