The importance of size reduction for cereal grains
In the particle size reduction process, reduction starts by destroying the outer protective layer of the seed to expose its interior. As size reduction continues, the amount of surface area increases and so with the amount of particles. Increased surface area is very important because the interior of the grains are exposed to digestive enzymes to provide the appropriate nutritional value from starch and protein. The overall effect is increased animal performance because livestock and poultry are able to absorb all the nutritive values that their bodies need. However, it is also essential to avoid excessive particle size reduction since it can result into digestive problems not to mention that it is waste of energy with unnecessary wear on the mechanical parts of the grinding equipment.
How the Hammer Mill works in particle size reduction
In a Hammer Mill, materials are introduced into the paths of the hammers that carry out the function of smashing the cereal grains to reduce their particle size. The design and placement of hammers is determined by the following operating parameters: rotor speed, horsepower and the open area of the screen. The number of hammers that are used in a Hammer Mill running at 1800 rpm should be 1 for every 2.5 to 3.5 horsepower; at 3600 rpm the ratio of hammers is 1 every 1 or 2 horsepower. There must be a proper balance on the way the hammers are arranged so they do not trail one another. While the hammers are carrying out their function, a perforated screen ensures that the particles reach the appropriate size through a specified maximum mesh size. The screen must be designed in a way that it can maintain its integrity and provide the greatest amount of open area. The screen holes are aligned in a 60-degree staggered pattern so as to optimize open area while maintaining strength.
The advantages of the Hammer Mill
The Hammer Mill can produce a wide range of particle sizes and works successfully with any friable material or fiber. In most cases, the particles produced through a Hammer Mill are spherical in shape with a surface that appears polished. However, the more popular reason why farmers prefer the Hammer Mill is the less initial cost of purchase if compared to the roller mill. Since there are no complicated operations on the Hammer Mill, it only requires minimal maintenance. Its drawback is noise and dust pollution but since the equipment is generally used outside outdoors, these issues hardly matter.