1. Teknologi Dan Rekayasa
TECHNICAL DRAWING

2. SECTIONAL VIEWS Objective :
After studying this lesson, the students should be able to :
1. determine when a workpiece should be represented in full view and when it is advisable to use half view.
2. apply the sectional views on the technical drawing
Teknologi dan Rekayasa

3. SECTIONAL VIEWS
In general, only hollow component are sectioned. This renders the internal spaces visible, they can be dimensioned in the sectional view and one view is often eliminated.
Here only one view is sufficient
Here two views are necessary, because
Hidden lines may not be dimensioned
Teknologi dan Rekayasa 3

4. SECTIONAL VIEWS
In a sectional view the component is regarded as being cut with a saw. The cut surfaces are cross hatched at 45° to the datum plane (it is left to the draughtsman to decide whether this is to the left or the right). These hatching lines (symbolic representation of the cutting marks) should be spaced approx 2 to 3 mm apart and be drawn with thin full lines.
45°
Teknologi dan Rekayasa 4

5. FULL SECTION
In a full section drawing the component is cut along the centre line. It is not necessary to indicate the path of the cut.
Teknologi dan Rekayasa 5

6. FULL SECTION A full section used when :
1. the view of component is asymmetrical
2. the external view of the component has no special features requiring representation. The component might also be symmetrical and it would then still be drawn in full section.
projection lines are drawn
through are hatching lines
Teknologi dan Rekayasa 6

7. HALF SECTION
In a half section, one half of the component is shown in section and the other half as a full view. The half shown as an external view are separated by a centre line (never by a thick line).
A half section is used when the view of the component is symmetrical and has projections, collars and grooves, etc. The sectional half is drawn on the left. However, in rotational symmetrical components it is drawn above the centre line.
Teknologi dan Rekayasa 7

8. PART SECTION
A part section or limited internal view of a component indicates that only a part of a component is shown in section or exposed (for clarity or dimensioning).
Teknologi dan Rekayasa 8

9. HATCHING LINES
The hatching lines are at 45° to the datum plane (it is the left or the right).
These hatching lines should be spaced approx 2 to 3 mm apart and be drawn with thin full lines.
45°
2 – 3 mm
Teknologi dan Rekayasa 9

10. HATCHING LINES
On the arrangement of the view, the hatching lines are must be used with the same method
To different parts and near view, use the different of hatching lines direction (left and right)
Teknologi dan Rekayasa 10

11. HATCHING LINES
The large plane can be used the hatching lines with the limit edge area.
Teknologi dan Rekayasa 11

12. EXAMPLE OF THE SECTION VIEWS
Teknologi dan Rekayasa 12

13. EXAMPLE OF THE SECTION VIEWS
Teknologi dan Rekayasa 13

14. EXAMPLE OF THE SECTION VIEWS
Teknologi dan Rekayasa 14

15. EXAMPLE OF THE SECTION VIEWS
Teknologi dan Rekayasa 15

16. THE END
Teknologi dan Rekayasa