The mechanical sample splitter shall have an even number of equal width chutes, not less than eight for coarse or combined aggregate, or twelve for fine aggregate. The chutes shall discharge alternately to each side of the splitter. For coarse and combined aggregate the width of the individual chutes shall be approximately twice the largest size particle in the sample to be reduced. For dry fine aggregate in which the entire sample will pass the 3/8 in. (9.5 mm) sieve, the minimum width of the chutes shall be at least fifty percent larger than the largest particles in the sample with a maximum width of 3/4 in. (20 mm).
The splitter shall be equipped with at least two receptacles (catch pans) to hold the two halves of the sample during splitting. It shall also be equipped with a hopper or straight-edge pan with a width equal to or slightly less than the overall width of the assembly of chutes, by which the sample may be fed at a controlled rate into the chutes.
The splitter and accessories shall be designed to allow the sample to flow smoothly without restriction or loss of material.
Mechanical splitters are commonly available in sizes adequate for aggregate having the largest particle size not over 1 1/2 in. (37.5 mm).