Rotating hammer samples

As to the different designs available in each of the two groups, the reader is referred to two excellent recent publications by Plowman2 and Merks5. One design worthy of a special mention is the cross-belt type cutter (or rotating hammer sampler) which swings in plane perpendicular to the movement of a conveyor belt and scoops a well-cut sample off the belt. Unlike the other, linear cutters, this one is not limited in its speed but it should traverse the bed of powder on the belt in the shortest possible time. 

In some instances the ball is dropped by allowing it to roll off an inclined track and is, therefore, rotating when it hits the sample. In the case of a no-fire, the ball bounces away from the block and only impacts the sample once, thus overcoming one of the inherent problems of multiple impacts produced by drop hammers. In other cases the ball is retained at the drop height and is released electromagnetically. The ease of sample testing, the low cost of the expendable... 

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