SAMPLING SCHEME
Increments are taken regularly during loading.Sampling location is dependent on Port and method of loading and accessibility to moving stream.
Arrangement are made with the grab operator to regularly position the grab at fix intervals on the ground. The outer layer should be pushed aside and increments are taken systematically.
SAMPLE PREPARATION
Sample division options: rotary division, riffle division, cone and quartering. It is not recommended to use cone&quartering unless there is no other option. Rotary sample division is most recommended.
Particle size is a key design parametar in determining the design and speed of the rotary divider.
Riffle dividers
Selection of the size of a divider is depending on the particle size and mass of the sample to be divided.
Cone & quartering
Division of Sub lot sample. This process should be done as quickly and carefully as possible to avoid loss of moisture and fine. Mix the sample on a clean dry floor (usually a steel plate or concrete). After mixing form the sample into a circle and flatten to a thickness of approximately 15cm. Divide the circle into 4 equal quarters. Select the opposite quarters. Two quarters reject, one is a sizing sample the other analysis sample.
Each Sub-lot sample is to be sized separately.
Size results for each sub-lot sample are then mathematically combined and a weight average reported for total shipment.
Size determinations depend on contract specifications.
Increments are taken regularly during loading.Sampling location is dependent on Port and method of loading and accessibility to moving stream.
Arrangement are made with the grab operator to regularly position the grab at fix intervals on the ground. The outer layer should be pushed aside and increments are taken systematically.
SAMPLE PREPARATION
Sample division options: rotary division, riffle division, cone and quartering. It is not recommended to use cone&quartering unless there is no other option. Rotary sample division is most recommended.
Particle size is a key design parametar in determining the design and speed of the rotary divider.
Riffle dividers
Selection of the size of a divider is depending on the particle size and mass of the sample to be divided.
Cone & quartering
Division of Sub lot sample. This process should be done as quickly and carefully as possible to avoid loss of moisture and fine. Mix the sample on a clean dry floor (usually a steel plate or concrete). After mixing form the sample into a circle and flatten to a thickness of approximately 15cm. Divide the circle into 4 equal quarters. Select the opposite quarters. Two quarters reject, one is a sizing sample the other analysis sample.
Each Sub-lot sample is to be sized separately.
Size results for each sub-lot sample are then mathematically combined and a weight average reported for total shipment.
Size determinations depend on contract specifications.
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