GB/T 6646-2008Chrysotile asbestos test methods (English PDF)

3.1

In addition to dry classification methods, other test methods used in the screen shall comply with GB/T 6003.1 requirements.

3.2

All the test water, the water temperature are 11 °C ~ 31 °C, the water must not contain visible sand, impurities and float.

Test Method 4

4.1 dry classification method for the determination and inclusion

4.1.1 equipment and instruments

a) chrysotile fibers Sieve. Model F500-I; Speed. 300r/min; mesh sieve aperture and wire diameter are shown in Table 1.

Table 1 F500-I-type mesh sieve classification requirements in millimeters

Project First level Second level Third level

Sieve aperture 12.5 × 12.5 4.75 × 4.75 1.40 × 1.40

Screen wire diameter u00d82.65 ± 0.04 u00d81.6 ± 0.02 u00d81.18 ± 0.015 b) balance. load is not less than 1000g, dividing the value of not more than 1.0g one;

Load is not less than 50g, dividing the value of not more than 0.01g one;

c) tweezers.

4.1.2 Sample Preparation

GB 8072 prepared by two samples of 500g. Water samples shall not exceed 3%, if exceeded, according to the standard 4.6 drying.

4.1.3 Test procedure

4.1.3.1

Adjustment of chrysotile fibers Sieve counter, so that the final result is 600r ± 0.5r.

4.1.3.2

The order placed on a screen by screen box frame. It should ensure that lined the upper and lower sets of positive.

4.1.3.3

The sample is placed in a container with GB 8072 in blenders conditioning to fully loose. Along the longitudinal direction evenly into the screen box sieve

Box.

4.1.3.4

cover screen cover, tighten the hand wheel.