A pin mill machine is a type of grinding equipment used for reducing particle size of materials by shearing them with a series of pins. It is commonly used in the food, chemical, and pharmaceutical industries for grinding materials such as sugar, salt, spices, and pharmaceutical powders.

The machine typically consists of a rotor with a series of pins or discs that rotate at high speed, and a stationary stater that surrounds the rotor. Material is fed into the center of the rotor and is sheared by the pins as it is transported towards the periphery of the machine. The finely ground material is discharged through a screen located at the bottom of the machine.

Pin mill machines can be used for a variety of applications, such as reducing particle size, homogenization of materials. They are suitable for processing materials that are heat-sensitive or have a low melting point, as the grinding action is primarily based on mechanical forces rather than heat.