A Text Book on Engineering Graphics - Central Board of Secondary ...

Example 5 :
Solution :
Steps Involved
Exercises
MACHINE DRAWING
Draw to scale, 1:1, the standard profile of a Knuckle thread, taking enlarged pitch
as 40mm
0.5P
Refer Fig.2.10
(i) Draw a thin centre line.
P 0.5P
P
40
0.5P
Fig 2.10
(ii) On either side of the centre line draw a row of tangential semi circles as shown
clearly in fig 2.10 Care should be taken in free flowing of semi circles into one
another.
(iii) Hatching and dimensioning is done as shown in fig 2.10
20
R=0.25P
0.25P
PROFILE OF A KNUCKLE SCREW THREAD
1. Draw to scale 1:1, the standard profile of BSW thread, taking enlarged pitch as
30mm. Give standard dimensions.
2. Draw to scale 1:1, the standard profile of metric thread (external) taking enlarged
pitch as 60mm. Give standard dimensions.
3. Draw to scale 1:1, the standard profile of metric thread (internal) taking enlarged
pitch as 60mm. Give standard dimensions.
4. Draw to scale 1:1, the standard profile of square thread, taking enlarged pitch as
60mm. Give standard dimensions.
5. Draw to scale 1:1, the standard profile of knuckle thread, taking enlarged pitch as
40mm. Give standard dimensions.
50 ENGINEERING GRAPHICS
10