Question

For a buttress thread, the distance between the crest and root (d) is ____ when pitch (p) is given.

(a) d= 0.86 p

(b) d= 0.5 p

(c) d= 0.64 p

(d) d= 0.75 p

I had been asked this question in quiz.

The above asked question is from Screw Threads in section Screw Threads & Screwed Fastening of Engineering Drawing

Answer 1

Right choice is (d) d= 0.75 p

To explain I would say: For a buttress thread the distance between the crest and root (d) is 0.75 times the pitch, for square thread ‘d’ is 0.5 times the pitch, for a Whitworth external thread ‘d’ is 0.64 times the pitch.