Question

Which of the following gives interference fit?

(a) Shaft ‘n’

(b) Shaft ‘p’

(c) Shaft ‘m’

(d) Shaft ‘g’

I have been asked this question during an interview.

I need to ask this question from Guide for Selection of Fits in section Limits, Fits and Gauges of Engineering Metrology

Answer 1

Correct choice is (b) Shaft ‘p’

To elaborate: Shaft ‘p’ gives a true interference fit and available in grades 6 or 7. With hole of grade 8 it behaves as transition fit. It is a standard fit for cast iron and steel. It can be used for fixing of a bush on a gear. Shaft ‘g’ gives clearance fit. Shaft ‘m’ and ‘n’ gives transition fit.