Question

Cores generally experience a single force called gravitational force in the mould.

(a) True

(b) False

This question was addressed to me in a job interview.

Asked question is from Forces Acting on Cores and Mold topic in portion Mold and Mold Making of Casting-Forming-Welding I

Answer 1

Correct choice is (b) False

To elaborate: When the core is placed in the mould, mainly two types of forces are present, one is the gravitational force acting on the core and another is buoyancy force which tries to lift the core in an upward direction due to the density difference between the core and metal. Core is generally lighter than the metal, which is used for the casting process.