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     The basis of the uniform blending of powder
 
 In the daily mixing process, the uniformity of material mixing directly determines the quality of the product. As we all know, absolutely nothing ideal phenomenon does not exist, so the absolute uniformity of powder mixing does not exist. The material mix evenly to the extent that they are relative to meet the product requirements for a uniform goal of the basic criteria. So how to improve the mixing uniformity, how to judge and test the uniformity of mixing by more and more enterprises.
          First, the definition of powder mixture ideal uniformity
        It is required that each of the powders participating in the mixing is equidistantly distributed between the particles and the particles, and all the powders involved in the mixing are evenly distributed up and down, left and right, and so on, which is the ideal degree of mixing uniformity. However, the actual situation is that the size of the powder particles can not be the same, the distance between each other may not be the same, so this ideal uniform distribution does not exist, the actual work of the powder uniform standard is to meet the product requirements of relatively uniform standards. Achieve process requirements is "uniform." To achieve uniform distribution of the product standard is uniform.
Second, the actual work of the powder mixed uniform standards
       1, Macroscopical uniformity: This is the first level of uniformity, macroscopically requires upper and lower containers, left and right sampling test, the result must be consistent with the proportion of various powder formulations, and containers can not appear dead ends , That is, macroscopically uniform. For example, the mixing principle of the three-dimensional mixer and the V-type mixer is the gravity diffusion type, which is easy to achieve macroscopical uniform, that is, the upper and lower parts of the equipment container are uniform.
       2, Uniform microscopy: This is the second level of uniformity, from the microscopic sample (sample size determines the size of the test requirements of the level of precision) observation, the particles are evenly dispersed between the powder distribution, and in line with the powder Body formula ratio, this is the microscopic uniformity. For example, the three-dimensional mixer and the V-type mixer can achieve a macroscopically uniform uniform distribution. Due to the lack of shearing means between the microscopic particles and the particles, it is difficult to achieve uniform microscopic dispersion.
Only one level of uniformity is not truly uniform, only at the same time reach the two levels of uniformity to achieve practical standards. For example, the macro parts of the test powder is basically uniform, and microscopic sample test found particles Baotuan, did not fully dispersed, so did not reach a uniform standard.
Third, how to improve powder mixing uniformity
        To achieve the macro and micro mixing of powder on the container requires the operation of the powder repeated flow, diffusion, hedging, folding and other sports so that the powder mixed with each other and infiltration, so as to achieve the macro-powder The purpose of mixing evenly; also requires the use of containers within the motion of the leaves forced powder stirring repeated, cutting and other activities, the micro-continuous break up the adjacent relationship between the powder particles, so that the full movement of the powder particles exchange, To achieve fine powder mixed materials on the microscopic. To achieve the perfect combination of macroscopic and microscopic, it is required to combine these two types of mixed movement organically to work together to improve the powder mixing uniformity.