GB/T 1868-1995 English PDF (GBT1868-1995)

This standard specifies the sampling and sample preparation methods for phosphate rock and phosphate concentrate. This standard applies to the collection and preparation of specimens for analysis of phosphate rock and phosphate concentrate products.

GB/T 1868-1995
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
Phosphate rock and concentrate - Methods of sampling and
preparing sample
ISSUED ON: DECEMBER 20, 1995
IMPLEMENTED ON: AUGUST 01, 1996
Issued by: State Bureau of Quality and Technical Supervision
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative references ... 4
3 Sampling and specimen preparation tools ... 4
4 Sampling method ... 4
5 Specimen preparation method ... 6
Phosphate rock and concentrate - Methods of sampling and
preparing sample
1 Scope
This standard specifies the sampling and sample preparation methods for phosphate rock and phosphate concentrate.
This standard applies to the collection and preparation of specimens for analysis of phosphate rock and phosphate concentrate products.
2 Normative references
The provisions in following documents become the provisions of this Standard through reference in this Standard. The versions indicated at the time of publication of this standard are valid. All standards are subjected to revision, AND parties who reach an agreement based on this Standard are encouraged to study if the latest versions of these documents are applicable.
GB 6003-85 Test sieve
GB/T 6678-86 General rules for sampling of chemical products
3 Sampling and specimen preparation tools
3.1 Sampling probes, small shovels, hammers.
3.2 Crusher, counter-rolling machine, grinding machine, sample divider. 3.3 Platform scales, sample holders, sample bottles.
3.4 Standard sieve (GB 6003) R40/3 series: 10 mm, 425 µm, 125 µm.
4 Sampling method
4.1 Number of samples
4.1.1 The total sampling amount of phosphate rock products shall not be less than 2/10000 of the batch size; the incremental sample size shall be 800 ~ 2000 g; the incremental sample sizes at each point taken in the same batch shall be similar. Figure 4 -- Schematic diagram of sampling layout
4.2.2 Sampling on the ship
If the cabin load is less than 100 t, arrange sampling points according to the sampling method from train carriage in 4.2.1. If it is greater than or equal to 100 t, arrange 20 points. If it is greater than or equal to 200 t, arrange 30 points, and so on. The sampling point is not less than 0.3 m away from the ship's side. Take incremental samples, at a depth of at least 0.1 m from the bottom and at least 0.2 m from the surface, using a sampling tool.
4.2.3 Sampling on the ore heap
On the entire surface of the ore pile, mark a number of horizontal lines, about 0.3 m from the bottom to the top, at an interval of about 1 m. Arrange sampling points at a certain distance on each line, according to Figure 4. If the total amount of ore pile is less than 50 t, arrange 5 ~ 10 points; if it is greater than or equal to 50 t, arrange 11 points; if it is greater than or equal to 100 t, arrange 20 points; if it is greater than or equal to 200 t, arrange 30 points, and so on. Take incremental samples, at a depth of at least 0.2 m from the surface, using a sampling tool.
4.2.4 Sampling on belt conveyor
According to the total amount of ore and the conveying speed of the conveyer, take incremental samples on the entire cross-section of any segment of the conveyer belt, using an automatic device or a small shovel, at regular intervals.
5 Specimen preparation method
5.1 Phosphate rock
5.1.1 After merging the individual samples taken in the same batch, make it subject to the steps of crushing, pulverizing, grinding and so on. Each step shall include sieving. Mix it using cone method or other methods. Use a divider or a quartering method to divide it. Each dividing shall be carried out according to the following formula: Where: