Q. How can you implement Permeability test
As already defined, permeability of porosity of the moulding sand is the message of its ability to permit air to flow through it. It is measured in terms of "Permeability number." In this test, a test specimen of moulding sand (50.8 mm dia. × 50.8 mm long) is placed in a tube. Time taken for 2000 cm3 of air at a pressure of 10 g/cm3 to pass through the specimen is noted. Then, the permeability number is given as:
P = V × h
p ×A× t
Where, P = Permeability number
V = Volume of a air passing through test
Specimen
h = Height of specimen p = Pressure of air
A = Cross-sectional area of specimen
t = time taken by air to flow through the
Specimen
Under standard conditions, the formula becomes
P = 2000 × 5.08
10 × ?/4 × (5.08)2 × t
= 50.128/t