Use of a mechanical splitter is considered to be the best method to reduce the gross sample of aggregate. The mechanical splitter splits the sample into two halves as the material passes through the spaces between the bars in the splitter. The same number of each particle size goes into each half of the sample, thus keeping the reduced sample representative of the total collected sample.
Adjust the splitter bars so that the bar opening is approximately 50% larger than the maximum particle size of the material to be split.
Place the mechanical splitter on a leveled surface and properly place the pans under the splitter in such a way that all of the particles diverting in both direction are caught.
Poor the sample evenly into the hopper.
Open the hopper fully and allow the material to fall freely through the splitter.
If wet particles stick inside the splitter, gently tap the splitter with a rubber hammer to loosen them.
To ensure that the sample has not been segregated during sampling, place both halves of the sample back into the hopper and repeat the splitting operation.
After the second splitting, the two receiving pans will contain approximately the same amount of material. Only one pan is placed back into the hopper and the splitting procedure repeated until a sample of the desired size is obtained. Skillful manipulation of the splitter allows a sample of nearly any size to be made that is still representative of the material in the stockpile.