Why Is The Pellet Mill Roller/Die Gap Very Important?

As well as preparing your raw materials correctly you have also got to setup your pellet mill correctly. One of the important procedures is setting the gap between the rollers and die.

By going through the information provided on other websites on making pellets, setting a gap to many people will sound strange. Many other pellet making websites basically state to force down the rollers to the surface of the die template. They state this is necessary to provide sufficient pressure and to build up enough heat. While it is true this will definitely generate enough heat, it is not good procedure and its not good for the die or rollers. The two reasons they state this is the pellet mills that they sell have a die that struggles to reach a sufficient temperature to melt lignin. Their dies also have very rough die holes, therefore clamping down the rollers is practically the only way to get material to flow through them. However the reality is in most cases that this will just lead to the die blocking. This all comes down to selling cheap Chinese imports without any knowledge of the proper process. Really you should be setting a roller gap of roughly 1mm for most materials. In some cases if the material is quite oily and of a low density you can increase this gap to maybe 2-3mm. However it is important to note that the larger the gap between the roller and die the more power that the motor demands. Therefore if you set the gap too high you may stall the motor. The benefits of a roller gap are that you will get better pellet compression and you will also get a much longer life from your rollers and die. The grease in your rollers and die will also keep in a better condition as it will be at lower temperatures. Please see below for videos on our small scale pellet presses and plants. We only use ring die pellet machines in our plants.