Question

The rate of flow of air passing through a standard specimen under a standard pressure is termed as _____________

(a) Green Strength

(b) Dry Strength

(c) Mould Hardness Number

(d) Permeability number

The question was posed to me in quiz.

This intriguing question originated from Moulding Sand Preparation and Conditioning in section Pattern Materials & Moulding Sand Tests of Foundry and Forging

Answer 1

The correct option is (d) Permeability number

Explanation: The standard permeability number test is to measure time taken by a 2000 cm3 of air at a pressure typically of 980 Pa to pass through a standard sand specimen confined in a specimen tube. The standard specimen size is 50.8mm in diameter and length of 50.8 mm.