Classifier of air flow pulverizer

The qualified powder produced by the air flow pulverizer is finished by the air flow pulverizer, and the quality of the finished powder mainly depends on the classifier It is one of the important parts of the air flow pulverizer, and also an important sign to distinguish the advantages and disadvantages of the air flow pulverizer The main function of the classifier of the air flow crusher is to timely separate the qualified powder in the air flow powder chamber without over grinding, which is one of the main differences between the air flow crusher and other mechanical crushers In addition, the powder sorted by the classifier of the air flow crusher is in a good dispersion state, which is beyond the reach of the single air flow classifier There are two main types of classifier in the air flow crusher, one is to use inertia classification, there are no moving parts in the classifier, such as the classifier in flat air flow crusher, circular tube air flow crusher and trotster air flow crusher, the other is centrifugal classification, the classifier has rotating impeller, and the particles are classified by the rotating centrifugal force field, There are single jet, counter jet and converging jet powder The separation of particles by the inertial classifier mainly depends on two parameters: one is the size of the jet with material or the velocity of the air flow; the other is the distance from the tangent of the velocity direction of the air flow to the turning center point, that is, the curvature radius of the point Therefore, it is not easy for the inertial classifier to adjust the size of separation particles Once the classifier structure is determined, only one parameter can be adjusted, that is, the speed However, for an air flow pulverizer, the exhaust volume and pressure of the air source are fixed, and the adjustment of the speed mainly depends on the size of the nozzle, which is very troublesome It can be seen that the air flow crusher with inertia classifier, such as flat type, circulation type and trotster type, generally produces a wide range of finished powder size cloth These aspects affect the wide particle size distribution: first, at the start-up and shut-down stage, the injection speed and gas volume change greatly, which seriously affects the particle size distribution of the finished powder; second, the air flow pulsation of the piston type air source causes periodic changes in the air flow speed and exhaust volume; third, the long-term use of the air source, due to the increase of the air flow resistance of the pipeline, reduces the pressure to the nozzle chamber, As a result, the jet velocity will change, and the particle size distribution of the finished powder will change with time.