Wiley mill

The Wiley mill is a laboratory-scale machine for grinding materials to a powder. This mill prepares materials for analysis with minimal moisture loss. Well-dried samples are preferred. In this grinding mill, the material is loaded cut into crude pieces or lumps and loaded into a hopper. From the hopper, the material drops by gravity into the path of a set of rotating hard tool steel blades (driven by an electric motor). The revolving knives work against stationary knives and the resulting powder is forced through a steel screen. The powdered material then drops into a waiting collection vessel underneath.

The Wiley mill is commonly used in agriculture and soil science laboratories.