1, negative pressure sieve analysis method
Before the sieve analysis test, put the negative pressure sieve on the sieve seat, cover the sieve cover, turn on the power supply, check the control system, and adjust the negative pressure to 4000—6000Pa.
Weigh the cement sample to the accuracy of 0.0 1g, put it in a clean negative pressure sieve, put it on the sieve seat, cover the sieve cover, and start the sieve analyzer for continuous sieve analysis for 2 minutes. In the meantime, if there is a sample attached to the screen cover, tap it gently to make the sample fall. After screening, weigh all residues with a balance.
2. Water sieving method
Before the sieve analysis test, adjust the water pressure (the water pressure should be 0.05 MPa±0.02 MPa) and the position of the water sieve frame to make it work normally, and control the distance between the bottom surface of the nozzle and the sieve to be 35 ~ 75 mm
Put the weighed cement sample 3m into a clear water sieve, immediately rinse it with clear water until most of the fine powder passes through, put it on a water sieve frame, and rinse it continuously for 3 minutes with a nozzle with a water pressure of 0.05±0.02 MPa. After sieving, flush the sieve residue into an evaporating dish with a small amount of water. After all the cement particles are precipitated, carefully pour out the clear water, dry it, and weigh out all the sieve residues with a balance.
3. Artificial sieve analysis method
Accurately weigh the cement sample to 0.0 1g and put it into a clean manual sieve. Shake the sieve back and forth with one hand and pat it gently with the other. The reciprocating shaking and flapping process should be kept close to the level. The flapping speed is about 120 times per minute, and it rotates 60 degrees in the same direction every 40 times, so that the samples are evenly distributed on the screen until the number of samples passing through every minute does not exceed 0.03g, and all screen residues are weighed.