Page 147 - CITS - ED - Mechanical

ENGINEERING DRAWING - CITS

Exercise 8.9
Sketch the views of a hexagonal bolt M10 x 50.
Proportion of bolt head and other features.
• Given bolt diameter = 10 mm (M10).
• Bolt head across flat = 1.5d + 3 mm
= 1.5 x 10 + 3 = 18 mm
• Bolt head thickness = 0.8d to 0.9d
= 0.8 x 10 = 8 mm
• Radius of chamfer = 1.5d or 1.4d
• Length of bolt = 3d to 4d approx
in this case = 50 mm.
• Sketch a regular hexagon of side 10 mm.
• Sketch a hidden circle touching the sides of the hexagon.
• Sketch a concentric circle of φ 10 mm. this is the plan of the bolt. (Fig 6)

Fig 6

• Sketch projectors from the corners of hexagon parallel to axis.
• Form a rectangle of the projectors equal to the thickness of the bolt head. (8 mm in this case)
• Sketch 30° lines as shown in Fig 6.
• Sketch arcs as shown in Figure 7.
• Sketch the shank to the specified length. Also sketch the threaded portion as per convention. (Fig 8)

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CITS :Engineering Drawing (Mechanical) - Exercise 8