GB/T 6730.2-2018Iron ores—Determination of moisture content—Gravimetric method (English PDF)

Foreword

GB/T 6730 "Iron ores" is divided into dozens of parts.

This part is Part 2 of GB/T 6730.

This part is drafted in accordance with the rules given in GB/T 1.1-2009.

This part replaces GB/T 6730.2-1986 "Methods for chemical analysis of iron ores. Gravimetric method for the determination of moisture content". Compared with GB/T 6730.2-1986, the main technical changes are as follows except for editorial modification.

- Added "Foreword", "Warning", "Chapter 2, Normative references", "Chapter 5, Sampling and sample preparation" and "Chapter 8, Test report";

- Replaced "Summary of Methods" with "Principle", and revised the expression of the principle (see Chapter 3; Chapter 1 of the 1986 edition);

- Modified the relevant expressions in "Instruments and tools" (see Chapter 4; Chapter 2 of the 1986 edition);

- Modified the specific requirements for the sample in "Analysis steps". the weighed mass, the requirements of the thickness of the sample (see Chapter 6; Chapter 3 of the 1986 edition);

- Modified the calculation formula of the analysis results, and added the provisions for the tolerance in the laboratory (see 7.2.1);

- Added the normative appendix "Acceptance procedures of the sample's analysis results" (see Appendix A).

1 Scope

This part of GB/T 6730 specifies the determination of moisture content in iron ore by the gravimetric method.

This part applies to the determination of moisture content in iron ore, iron concentrate, sinter, and pellets.

2 Normative references

The following documents are essential to the application of this document. For the dated documents, only the versions with the dates indicated are applicable to this document; for the undated documents, only the latest version (including all the amendments) is applicable to this standard.

GB/T 8170 Rules of rounding off for numerical values and expression and judgement of limiting values

GB/T 10322.1 Iron ores -- Sampling and sample preparation procedures

3 Principle

Place a certain amount of samples in a drying oven, dry at 105 °C ± 2 °C to get constant weight; measure the loss of the mass, and calculate the content of the moisture.

4 Instruments and tools

4.1 Electronic platform scale or balance. the range is 2000 g; it shall be accurate to 0.5 g.

4.4 Mixing sample plate. a smooth, clean, stainless metal plate or glass plate (about 100 cm × 100 cm).

4.5 Mixing sample shovel. The surface shall be smooth, clean; it shall be made of stainless metal plate.

4.6 Sample tube. it shall have a cover; it can hold 5 kg of sample.

5 Sampling and sample preparation

Take and prepare samples according to the method specified in GB/T 10322.1; the particle size is less than 20 mm.

6 Analysis steps

Move the sample to be tested from the sample cylinder (see 4.6) to the mixing sample plate (see 4.4), and quickly mix well with a mixing sample shovel (see 4.5).

7 Result's calculation and its representation

8 Test report

The test report shall include the following. […]

Appendix A (Normative appendix) Acceptance Procedure of the Sample's Analysis Results

The acceptance procedure of the sample's analysis results is shown in Figure A.1. […]