Question

Which of the following is incorrect?

(a) V-Anvil micrometer caliper is used to check out of roundness

(b) Blade type micrometer has a non-rotating spindle

(c) Tube wall thickness can be measured by an ordinary micrometer

(d) Self-centering inside micrometer has an interchangeable measuring head

I have been asked this question in an online interview.

My question comes from Micrometers topic in section Linear Measurements of Engineering Metrology

Answer 1

Right choice is (c) Tube wall thickness can be measured by an ordinary micrometer

The best explanation: An ordinary micrometer can’t be used for measuring tube wall thickness because of the concavity of internal surfaces. For this, anvil is made of cylindrical form and spindle axis and anvil axis is made perpendicular.