|The universal grinder grinding technology was introduced to China in the last 70 years, it appears to promote the development of the food processing, pharmaceutical, chemical and other industries. So ultrafine grinding and traditional purely mechanical crushing method essentially different, this technology due to the impact crusher material into the crushing chamber by the high speed rotation of the six activities hammer impact, by the ring gear and materials colliding and grinding, materials to be crushed under the help of the airflow through the sieve into the Sheng chalk bag, leaving no residue. With high efficiency, low noise, work performance and product quality is reliable, the advantages of operating safety, health and loss of small drugs. Not appear so in the process of crushing the local hot spots, and the speed with fast, often instantly to complete, but also to maximize retain a bio-active ingredients of the powder.
Smash is one of the most important production processes in the feed mill. The the crushed can feed exposed surface area increases, which will help livestock digestion, absorption, bit conveying, batching, mixing, granulation and subsequent work more convenient. Purpose of grinding feed sometimes some special circumstances, such as crushed hay powder in order to transport, mixing and pressure tablets processes carried out smoothly, crushing some additives raw materials in order to obtain a fine enough
Crushed particles, to increase the number of particles in order to ensure uniform mixing, then, need to use micro-pulverization or Attritor.
At present, the common feed grinding apparatus: grinder, roll mill, a jaw crusher, special pulverizer and several.
Universal grinder mainly by the feed section, the grinding chamber and the suction system. Structural components from the hopper, upper body, lower body, chassis, rotor, sieve. Work, the material through the feed inlet into the crushing chamber, is high-speed movement of the hammer impact crushing, being crushed at the same time may also obtain a higher speed, direct control of the pulverization chamber wall on the tooth plate broken again and reflecting it back, the reflection the material back and hammer repeatedly hypervelocity impact was crushed. Under the action of fan, less than the mesh granules and powders quickly sieved, and along the pipeline are sent to the cyclone or deposition chamber. The hammer mill has a simple structure, adaptability, high productivity and the use of safety advantages. It contain high fat meal, containing more fiber fruit chaff and straw, containing high protein plastic material, higher moisture content of the grain can be crushed, can be a multi-purpose machine.
The universal grinder mechanism is extremely complex. Though there have been a lot more careful study, there is a degree of understanding, but is far from complete control of its regularity, yet to be depth.
1, the particle size distribution
Under normal circumstances, a separate solid material after pulverization by a sudden blow, will produce a smaller number of large particles and the small particles of the number, of course, there is a small amount of intermediate size particles. If it continues to increase the energy of the blow, the large particles into smaller particles, while the small number of particles will be greatly increased, but the fine powder of particle size no smaller. This is because the bulk materials have a more or less within the fragile surface material force after the first fragmentation occurs along these fragile back. Material particle size is small, these fragile surface gradually reduce the particle size of the final material close to constituting the crystal unit block (silver inlay blocks), small particles forces often do not fragmentation, only surface by cutting a certain particle size particles. Thus, the small size of the particles is determined by the nature of the material, while the particle size of the large particles have a close relationship with the comminution process, as shown in Figure 1-2, a series of experiments coal was pulverized with a ball mill confirmed the above relationship. The initial particle size distribution shows a single peak, which corresponds to relatively coarse particles e, but with the grinding process progresses, the peak gradually decreases, and to produce a second peak in a certain granularity, this process has been to The first peak pattern disappears completely. The second peak is characteristic of the material, known as persistent peak type, while the first peak pattern called a temporary formation.
Second, the pulverization energy utilization
The crushing energy use efficiency and its rate is applied very close relationship. Reached, typically a time lag between the maximum load Hu pulverized. Therefore, under the premise of holding the full role time, a smaller force will cause the pulverized particles. The application of energy appears pulverized interval is a function of the rate of energy application. Applying the faster the rate, the lower the energy use efficiency. It is easy to infer that provide nothing more than the pulverizer energy consumption in each of the following aspects:
(1) is consumed in the pre-crushing the particles themselves on the elastic deformation;
(2) generates a non-elastic deformation resulting pulverized;
(3) the grinder itself elastically Distortion;
(4) to overcome the frictional resistance between the particles Q and particles with mechanical;
(5) generates a noise, heat, and mechanical vibrations in the pulverization;
(6) pulverizer operation portion of the friction loss of c
According to the analysis estimates that only about 10 percent of the power consumed by the province to effectively use rationalization, is to study the mechanism of the charge and shredding process. Lee of energy for the grinding process