SN/T 1039-2020Sampling and sample preparation method of imported and exported ton packaging silicon carbide (English PDF)

4.1 Overview

Quantitatively packaged silicon carbide is generally 60 t as an inspection lot. Sample packages are randomly selected according to the number specified in Table 1.The specific sampling method is as per 4.5 Require execution. 5% of each batch can be poured randomly, and 0.5 kg samples are randomly sampled from the middle and lower parts with a sampling shovel, and the rest is carried out according to regulations. If not Enough for one inspection lot, less than 30 t (ton packaging), use the bag-by-pack sampling method; if the particle size is not uniform, use the upside-down three-shovel method;

For degrees below 10 mm, use the skewer diagonal method. Refer to Appendix A for examples of quality fluctuation evaluation, and refer to the appendix for the accuracy calibration method.

Record B.

Note 1.SW is quality fluctuation.

Note 2.Sampling package by package for less than 30 bags per ton.

4.2 Sampling tools

4.2.1 Sampling shovel. a clean shovel with a volume of about 125 cm3.See GB/T.2007.1 for specific dimensions.

4.2.2 Sample drill. made of stainless steel with phi15 mm×500 mm (phi30 mm×750 mm).

4.2.3 Sample container with lid or clean plastic bag.

4.3 Number of incremental samples (number of sampling packages)

4.3.1 The minimum number of copies should be taken as shown in Table 1.

4.3.2 Sampling of 50 kg packaging can be carried out according to GB/T 6679.The number of copies (N1) of different batches is calculated according to formula (1).

4.4 Incremental sample size

4.5 Sampling method

4.5.1 Packet-by-packet sampling method

Sampling with a sampling shovel, take approximately 0.5 kg aliquots from 30 cm to 50 cm below the mouth of the bag. Sampling with a sampling drill, which is completely diagonal from the mouth of the package Insert, rotate the skewer 180, take about 0.5 kg sample.

4.5.2 Three shovel method

According to the type of batch and quality fluctuation (see appendix B), sample packages are randomly selected according to the number of copies specified in Table 1, and the packages are poured in a neat and tidy state.

On a clean iron plate or concrete floor, forming a cone shape, insert the sample shovel into the center of the circle from the three busbars of the outer ring of the cone bottom at an angle of 120°, and then Lift up vertically to take a total of 3 scoops, each bag totaling 0.5 kg.

4.5.3 Skewer diagonal method

Randomly draw sample packets according to the number of incremental samples specified in Table 1, open the bag mouth and insert the skewer diagonally from the top, and rotate the skewer.

180°, take out about 125 g of the sample, and take a total of about 250 g of partial sample on the second skewer.

4.5.4 Sample storage

The moisture sample should be placed in a clean and sealed container, and the moisture content should not change before the measurement.

5.1 Sample preparation tools

5.1.1 Sampling shovel (same size as 5.2).

5.1.2 Jaw crusher. SP100 mm×60 mm.

5.1.3 Sealed oscillating grinder.

5.1.4 Divider (see GB/T.2007.2 for specifications).

5.1.5 Sample shovel and baffle.

5.1.6 White iron surface mixing table or rubber plate surface mixing table.

5.1.7 Magnet. 10 N~15 N magnetic force.

5.1.8 Sample holder. 900 mm×450 mm×100 mm (0.8 mm ordinary steel plate).

5.1.9 Brush.

5.1.10 Wide-mouth glass bottle with frosted stopper (capacity about 100 mL).

5.1.11 Sample sieve.

5.2 Sample preparation procedure

The water and analysis samples can be prepared simultaneously or separately according to the procedure shown in Figure 1 as needed.

5.3 Reduction method

One or several of the following methods can be used in combination.

a) Divider reduction method. execute according to GB/T.2007.2.

b) Grid reduction method. implemented in accordance with GB/T.2007.2.The sample thickness shall be executed according to Table 3.

c) Four-division method. According to GB/T.2007.2.

5.4 Sample container and label

The analysis sample should be placed in a matte stopper jar or a closed container and attached with a label. The following items are indicated on the label.

a) Number;

b) Product name, grade, category, and place of origin;

c) Number (quality). bag (t);

d) Sampling and sample preparation personnel;

e) Sampling, sample preparation location, date and weather.

6.1 General rules for sampling

Quantitatively packaged silicon carbide is generally 60 t as an inspection lot. Randomly select sample packets according to the number of samples specified in Table 4, and use a sampling shovel to separate the bags from 30 cm to 50 cm below the mouth, take approximately 1 kg of incremental samples. At the same time, take 10% bags from the number of samples specified above, from each bag Take about 1 kg of the lower part of the sample. If a sampling skewer is used for sampling, insert it into the bag diagonally from the mouth of the bag and rotate it 180° to take about 0.5 kg increments.

If there is not enough one inspection lot and less than 30 t (ton packaging), the sampling method can be selected package by package; if the particle size is not uniform, three shovel can be selected Method; if the particle size is below 10 mm, you can choose the diagonal of the skewer...