A hammer mill and a roller mill will enable you to achieve your desired result. However, you also have to consider other factors before you choose the method for grinding. You need to keep in mind that if you excessively reduce the size of the material, you will be wasting electrical energy which usually results in an unnecessary wear on the equipment used.
The general design
The major component of a hammer mill is a delivery device which is used to guide and introduce the material that is to be hammered and placed in the path of the hammer. There is also a rotor that is made up of a series of disks mounted on the shaft that is horizontally positioned. There are also free swinging hammers that are perched from rods which is strategically placed parallel to the horizontal shaft and placed through the rotor disks. The hammers function as the smashers of the material fed into the machine in order to reduce the size of the material. A perforated screen will assist in the grinding of the material and will ensure that the hammer mill smashes the material until the desired particle size is achieved.
The different materials fed into the paths of the hammers are placed through a variable speed feeder. This unique feeder can have its motor controlled by a program. The feeder’s operational speed is also controlled in order to ensure that optimum amperage loading is maintained on the main motor.
Hammer configuration and design
The placement as well as the design of the hammers in the machine is typically determined by operational parameters like the motor horsepower, rotor speed and the open area on the screen. When the design and placement of the hammer is optimum, it will provide you with a maximum contact with the material fed on the machine.
What will determine the grinding efficiency and the resulting particle size in hammer mills? The answer to this question is the amount of open area that is available in the hammer screen. The screen should be designed in a way that it will maintain its integrity and provide the machine with the greatest open area in order to work efficiently.
Screens with holes that are aligned along a 60 degree pattern can optimize open area and maintain the strength of the screen. Using this method, a 40 percent open area will result.
You should also pay attention to the ratio of the horsepower to the open screen area. The recommended ratio for this kind of work is 55 square centimeter per horsepower. When there is no enough open area for every corresponding horsepower, this will result in heat generation. When the heat exceeds 46 degrees Celsius, the capacity of the machine will be decreased by 50 percent.