Quality quantitative analysis of wall putty making machine

In the production process of putty powder, how to identify the mixing quality of putty powder mixer and how to quantitatively analyze the mixing quality of putty powder mixer? From the physical point, the fourth stage of GMP certification for putty powder mixers such as two-dimensional motion mixers or other powder mixing equipment-performance verification (PQ), mentions the detection of mixing uniformity (RSD). Undoubtedly, mixing uniformity is the most important index for evaluating the performance of wall putty making machine.

• The definition of mix manufacturing process of wall putty making machine.

  
  

1. The mixing principle of the wall putty making machine is actually the process of mixing two or more components in a dry state or in the presence of a small amount of liquid under the action of an external force to continuously reduce their heterogeneity. The so-called two or more components can be different substances, or the same substance with different physical properties: such as different water content, different particle diameters, different colors, and so on.

2. Powder mix processing is a complicated random process, the evaluation and measurement methods of mixing quality have always been a thorny issue that plagues people. With the development of the times, the days of judging the uniformity of mixing based on human senses have passed. Using scientific and quantitative methods to determine the uniformity of mixing is the quantitative analysis of powder mixing. To achieve quantitative analysis, there must be several processes of sampling, testing, and statistical analysis (data processing) to obtain a single value to express the uniformity of the mixture.

• Sampling of mixture in wall putty making process machine
  

1. Sampling is an action to take out a small amount of material mixture from a certain position of the wall putty making machine, this small amount of material is called "observation sample" or "point sample", the sampling location is called "sampling point".

2. In the same wall putty making machine, at the same time, samples taken at different sampling points constitute "samples" at this time level. The number of point samples is the sample scale. Regarding the scale of the sample: the smaller of the sample the better if it meets the required amount of testing and may be representative of the materials around the sampling point. If the sample is too large, it not only wastes materials, but also detrimental to the accuracy of quantitative analysis.

3. Regarding the number of samples (ie the scale of the sample): the more the number of samples, the larger of the sample scale, the more reliable in quantitative analysis results and the smaller error rate. But so far, the determination of the optimal number of samples has not been fixed. According to the recommendations of the American Chemical Engineering Association, 5 to 15 samples are required, and some people think that at least 20 or even 50 samples are required. In our country, it is usally to take 5-10 samples. Regarding the location of the sampling point, when the material is in a static state, the sampling points should be distributed as evenly as possible in each position of the material. If the sample can be taken in the moving state of the mixture, the analysis result is more accurate than static state. Therefore, when conditions permit (such as the optimal mixing time has been determined), it is better to take the sample in the mixer outlet port.

• Mixture inspections that mixed by wall putty making machine.

Use chemical or physical methods to inspect each component (especially the key component-tracer) of the samples: X. If the number of samples is 5, there are 5 results will be inspected and recorded as : X1; X2; X3; X4; X5. The inspection method should be determined by the nature of the components, the purpose of mixing and the actual conditions.

• Statistical analysis of mixing quality of wall putty making machine  in mixing process of putty powder.

The above inspection results are calculated by statistical methods to obtain a single value to evaluate the mixing quality of the mixture, it is statistical analysis.

• Arithmetic, also named as sample average value: X

    X=—Σxi

    In the formula: n is number of point samples (sample scale)

    Xi, The measured parameter of the i-th sample. Such as quality, water content, particle number, etc.

• Variance: σ2

    σ2=Σ(Xi-X) 2

• Standard deviation,

    Also named  as SD (abbreviation for Standard Deviation): σ

    σ=√σ2=√——Σ（Xi–X）2

Before the 1940s, σ has been used to define (evaluate) the quality of powder mixing. The smaller the value of σ, the more uniform the mixing. However, practice has shown that this definition not so accurate in some cases and the error is large. British powder engineering authority N. Harnby said in his monograph "Mixing Process in Industry" (Sinopec Press 1991): "...the practical variance obtained from the sample (Σ2) value does not so critical unless it can be related to the limit variance value".

Relative standard deviation,

• also named as RSD (RelativeStandardDeviatio): V
  

    There are many algorithms for V, here only 2 common algorithms are provided below.

    Algorithm 1: V=×100%

    Algorithm 2: V=(×100%)

All in all, the uniformity of the mixture has become an important quantitative criterion for judging the mixing quality of the putty powder mixer. In the actual operation process, there is also an important quantitative criterion that is the output of the putty powder . Under the premise that the mixing uniformity reaches the standard, the output becomes measure another performance index of the mixer. A series of dry powder mixing equipment such as Ant Construction Putty Powder Mixer and Stone Texture Paint Mixer are all under the premise of ensuring the quality of mixing. Through scientific and technological meathod, the level of automation of the equipment is improved, thereby increasing the output of the equipment. Any demand for putty powder mixer machine and production line,  stone texture paint strirring mixer machine, dry powder mixing equipment, such as dry powder mortar, please visit our website.

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