How do smaller grains work?
It has been found that the smaller garnet grains work because of their size, specific gravity and hardness. There are approximately 11 million grains of (GMA Garnet 30/60) garnet per kg as opposed to 1 million grains of (20 mesh) slag per kg. As garnet has 11 times as many impacts per square centimetre, it stands to reason that the surface will be cleaned much faster than with a larger grain abrasive. We have now determined that smaller grains clean faster because there are more of them. The abrasive valve must be closed down because the abrasive mixing with the air needs to be reduced to achieve the desired abrasive velocity. In closing this valve down, abrasive consumption is reduced (a cost saving) and the blast pot time before refill is extended 2-3 times that of a slag pot, resulting in less stopping and higher productivity.
