GRADES OF POWDERS

GRADES OF POWDERS: 

Grades (Types) of powders are expressed on degree of Coarseness and Fineness of powder.

1) Coarse Powder: A Powder, all the particles of which pass through a sieve with a nominal mesh aperture of 1,700 micron meter and not more than 40% by weight through a sieve with a nominal mesh aperture of 355 micron meter.

2) Moderately Coarse Powder: A Powder, all the particles of which pass through a sieve with a nominal mesh aperture of 710 micron meter and not more than 40% by weight through a sieve with a nominal mesh aperture of 250 micron meter.

3) Moderately Fine Powder: A Powder, all the particles of which pass through a sieve with a nominal mesh aperture of 355 micron meter and not more than 40% by weight through a sieve with a nominal mesh aperture of 180 micron meter.

4) Fine Powder: A Powder, all the particles of which pass through a sieve with a nominal mesh aperture of 180 micron meter and not more than 40% by weight through a sieve with a nominal mesh aperture of 125 micron meter.

5) Very Fine Powder: A Powder, all the particles of which pass through a sieve with a nominal mesh aperture of 125 micron meter and not more than 40% by weight through a sieve with a nominal mesh aperture of 45 micron meter.

6) Micro Fine Powder: A Powder, of which not less than 90% by weight of the particles pass through a sieve with a nominal mesh aperture of 45 micron meter.

7) Super Fine Powder: A Powder, of which not less than 90% by weight of the particles pass through a sieve with a nominal mesh aperture of 10 micron meter.