Calculation method of chromite sand AFS fineness:
The measurement steps and calculation methods specified by the American Casting Association as specified in the AFS fineness are as follows:
1. First call it about 50g of the measured sand sample, wash off the mud, dry, and then screen;
2. The quality of the sand grains stayed on each sieve;
3. Calculate the percentage of the total amount of sand and granulation on each sieve;
4. Multiplying the percentage of the amount of sand particles on each screen multiplied by the “AFS fineness multiplication” corresponding to each sieve;
5. Add the product obtained by each sieve number above, and the sum of the total:
6. The sum of the 5th item, in addition to the sum of the percentage of the amount of sand in each sieve, the AFS fineness is obtained. “AFS fine degree multiplication” corresponding to each screen number
Then find the average value to get the average fineness of chromi sand.