Question

What is the major diameter tolerance of effective diameter for external threads?

(a) +0.01√p

(b) -0.05√p

(c) +0.05√p

(d) -0.01√p

I have been asked this question in quiz.

I'd like to ask this question from Tolerance for Screw Thread Gauges and Screw Threads in section Metrology of Screw Thread, Gauges for ISO Metric Screw Threads of Engineering Metrology

Answer 1

The correct choice is (a) +0.01√p

Easiest explanation: In major diameter, the tolerance is given by expression Effective Diameter tolerance = +0.01√p.   It is applicable for all grades of fits for external threads. In major diameter, no such tolerance is laid down for internal threads.