Powder fluidity test - powder properties analysis solution - Database & Sql Blog Articles

Powder fluidity test

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Powder Characteristics Analysis Solution - Next Chapter

This measurement method is currently used on the market or a multi-functional particle and powder characteristic analyzer (

FT-2000A

), which is also a highly intelligent instrument at present, generally used for paper writing and corporate quality control or higher recognition.

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For your reference

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3.2.

Shearing method

The shearing method is a relatively advanced measuring method. It is also a relatively common method used in the old industrial countries in Europe and America. It is more inclined to describe the intrinsic properties of bulk solid materials such as internal friction and wall friction. Flow characterization of powder,

Jenike

method

,

The characteristics of powder flow behavior were analyzed by ring shear method, and the data model was established.

PC

The combination of software, real-time dynamic analysis of powder shearing, consolidation, time, stress and strain relationship, yield strength function, establishing Mohr circular damage envelope, flow factor, effective internal friction angle, yield trajectory, Flow function,

Jenike

Liquidity index

FI

Judging the flow and non-flow and critical points, calculating the hopper half-angle, the powder void ratio, the relationship between looseness and compaction,

This method personally feels that it is more suitable for research institutes and universities or large enterprises with certain strength. Why do you say that the analysis method is too complicated and requires more theoretical knowledge. If it is not a professional powder practitioner or researcher, It is difficult to master completely. At present, it is used in large enterprises and universities. In this way, analyzing and writing papers or developing new products generally has higher reliability and future predictability analysis, especially for The design of the powder equipment is very helpful.

What is currently used more in the industry is

Powder flow behavior dynamic analyzer (

FT-3400

) The degree of intelligence is relatively high, basically providing a large amount of analytical data in the analysis process, and analyzing it well is a good choice for researchers.

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3.3.

Drum method

The drum method is to fill the drum with the powder particles to make it rotate slowly, and determine the number of times the particles collide every revolution of the rotating roller at a fixed speed. The greater the number of times, the better the fluidity; the smaller the flow, the worse the fluidity. This method reflects the stability, critical transition and collapse scale of particle flow.

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And mass flow rate

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Meet the requirements of the European Pharmacopoeia

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The surface of the particles in the drum can be divided into top to bottom depending on the flow rate.

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Areas: sparse flow area, dense flow area and creep zone; the change of shear rate has a decisive influence on particle flow characteristics and motion state; the movement of particles in the drum has a significant feature, which can be roughly divided into flow The surface layer and the stationary bottom layer are organically unified by the development of particulate matter from a stationary state to a flow, and then from a flow through a blockage to a stationary process. By adjusting the rotational speed of the drum, the flow and flow state of the particles can be obtained.

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According to the thickness of the particle flow layer or the free surface inclination angle in the drum, the shear rate of the fluidized layer is obtained, and the fluidity of the particulate matter is calculated.

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The shear deformation rate of the particles in the dense flow region from the center to the free surface at different rotational speeds and drum diameters has a linear variation characteristic, the average shear rate, the average shear deformation ability of the particle flow, particle size, shape, friction Factors such as factors and flow conditions.

Although this method is less used in China than the previous two methods, the uniqueness of this method is comparative theory. To put it simply, the analysis of the data can improve the ratio of powder research and development. Said more abstract than the previous method, more suitable for scientific research use

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Drum method powder flow tester (

FT-7100

) is what I know,

3.4.

Yield strength method

When the particles are compressed, they undergo a series of changes such as initial compression, particle rearrangement, initial structure formation, elastic deformation, plastic deformation, particle breakage, bond formation, further compaction, and elastic recovery after pressure removal. The particle structure is destroyed and occurs. Recombination to form new binding bonds and compressed bodies;

Applying the principal stress required for deformation of the yield strength,

To analyze the relationship between the volume change and pressure of the powder (the relationship between the principal stress and the powder density), the relationship between the time and the yield strength, and the relationship between the yield strength and the compression height, using the empirical equation method:

Heckel

,

Kawakita

,

Adams

The equation and the compression theory of the linear regression equation of the North Sichuan equation to analyze the new powder particles, develop solid products such as drug prescription and process selection, and the requirements of compaction density and pressure requirements.

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Powder hardness tester

FT-3500