ISO 728-2021 pdf download.Coke一Size analysis by sieving.
7.2 DivIsion of coke mInus 22,4 mm
Divide the sample (minus 22,4 mm lraction from 71 e) to the required minimum mass in TablvJ.
means of a suitable mechanical sample divider or riffle avoiding size degradation and loss of dust. Alternatively, for division. use either the flattened heap method or the strip mixing method described In ISO 13909-6 and ISO 18281 Determine the mass of all the coke not included is part of the test sample and retain It until all analyses and calculations are complete.
7.3 SlzI.g sample 01 maximum particle size between 224 and 4mm — Manual method
a) Determine the mass (of the dwided minus 22,4 mm traction from 72) of the sample to the nearest
0,1 %.
hI Position the largest aperture size sieve In the set over an empty receiver or hin Move the sieve horizontally to and [ro. with the displacement not exceeding 100 mm in either direction, to c.luse the pieces of coke to tumble or roll on the sieve.
c) Continue the sieving motion until eight movements In each direction (a total or 16 movements) )save taken place after the last undersize piece passes through the sieve Avoid any impact when stopping the motion.
d) Place the coke remaining on the sieve In a tired receiver and determine the mass of the size traction.
e) Sieve the undersize again by repeating the above process for each sieve down to and Including the 4,0 inns aperture size sieve and redetermine the mass cii each size fraction including the inlnu
4.0mm fraction.
Th. mass of the minus 4.0mm fraction from 7.3 r) may also he reduced in a similar faihism to 72 beFore proceeding to 7.4.
7.4 SIziag sample of particle size less than 4.0mm — Manual method
a) Determine the mass lot the divided minus 4.0mm fraction from 7.3 e) to the nearest 0.1 %.
b) Place the smallest aperture size sieve in the set on a receiver or bin. Brush the sample onto the sIeve. fit the lid and sieve continuously for a S mm (minute) period, as described in iteffi c), to remove the undersize. lithe sample Is large, sieve it as separate portions so that not more than 75% of the area nithe sieve Is covered at the end or each sieving operation.
c) Hold the receiver, fitted with the sieve and Its lid mn the left hand so that the surface at the sieve Is inclined downwards towards the left at an angle of about 30 to the horizontal, Tap the higher side of the sieve frame six to tight tlnses with the hardwood block. While m.ilntaining the inclination of the sieve, shake the assembly to and ho several times, also rotating 8 in the plane at the sieving surface through an angle of approximately 60
d) Continue the operations olsapping.ind shaking alternately fur a further S nun period.
e) At the end of the further S mm sieving period, allow the suspended tines to settle for 2 mlncarefully remove the lid and lilt the sieve from the receiver or bin, Invert the sieve over a tray, tap the higher side of the sieve frame with the hardwood block, and then carefully brush thc uppermost surface of the inverted sieve with the fLit brush. Turn the sieve the right way up and add any loose particles dislodged during brushing to the overslt.e on the tray.
1) Invert the receiver over a second tray. Lisp the rece4ver with the hardwood block and brush out any adherent tines.
g) II there are any fines still visible in the oversize, replace the sieve on the receiver and transfer the oversize from the lirat tray to the sieve, replace the lid and re-sieve 8x a Further 5 mm period. Separate the sieve and the receiver and again, dean the sieve. Add the tines to the material which passed through the sieve during the first and second S mm periods.ISO 728 pdf download.