Roller Mill

A roller mill is a mill that uses cylindrical rollers to grind various materials including grain, ore, gravel, plastic, etc. It is a cheaper alternative to traditional millstone arrangements in gristmills. There are three main types of rollers, distinguished by the number of rollers. The two-roller mill is the simplest variety where the material is crushed between two-rollers before it is sent out. The spacing on this machine can be controlled, allowing the user to adjust granularity. A four-roller mill has two sets of rollers which work to separate the seed from the husk without damaging the husk, leaving large grits from which flour is sieved. Five-and-sick-roller mills have up to three sets of rollers which further separate the grain grinding process.