Mining Methods and Machinery · Mining Methods · 1 mark · Numerical answer
In-situ coal density is1320 kg/m³ and blasted coal density952 kg/m³. Find the swell factor to three decimals, using the convention in the official key.
For equal mass, the ratio of bank volume to loose volume is loose density divided by bank density. Thus the keyed swell/load factor is952/1320=0.721212, or0.721. Some texts call the reciprocal1.3866 the bulking ratio; explicitly stating the convention avoids interchanging the two.