A sieve is a further device for measuring durability. Although not all standard
procedures for sieving are suitable, those which comprise the use of balls between the
screens can be used. By vibrating a pellet sample in a sieve apparatus, abrasion and
perhaps fragmentation will occur through the action of (rubber) balls. Variables in this
device are the sieve openings, the number of balls, the amplitude, screening time and
eventually the use of interval sieving. Particle size distribution obtained by dry sieving
may add useful information when the influence of sieving (under standardised conditions)
for example is expressed in terms of the modulus of fines or the modulus of
uniformity before and after sieving (Pfost and Headley, 1976).
A sieve is a further device for measuring durability. Although not all standardprocedures for sieving are suitable, those which comprise the use of balls between thescreens can be used. By vibrating a pellet sample in a sieve apparatus, abrasion andperhaps fragmentation will occur through the action of (rubber) balls. Variables in thisdevice are the sieve openings, the number of balls, the amplitude, screening time andeventually the use of interval sieving. Particle size distribution obtained by dry sievingmay add useful information when the influence of sieving (under standardised conditions)for example is expressed in terms of the modulus of fines or the modulus ofuniformity before and after sieving (Pfost and Headley, 1976).
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