• Categories:News Center
• Time of issue:2022-05-06 11:31

(Summary description)In the daily project consultation, when some customers consult the powder conveying project, they often do not understand the characteristics of the material and the characteristics of the powder when talking about the characteristics of the conveyed materials, so today I will introduce the characteristics of the powder. Knowledge about the properties of some powders. The aggregate of a large number of solid particles is called powder, which represents a state of existence of matter. In industrial production, we need to quantitatively reflect its particle size. The particle size of the powder is one of the basic indicators reflecting the characteristics of the powder, which affects the physical, chemical, mechanical properties of the powder and its performance. What are the characteristics of powder? 1. Particle size of powder Particle size, also known as particle size, is short for particle size measurement. The actual particles are composed of coarse and fine particles, so when talking about particle size, the correct expression is to give a particle size distribution, that is, what is the percentage of coarse, medium and fine. 2. Bulk density of powder Bulk density refers to the density obtained by dividing the mass of the powder by the volume V of the container occupied by the powder, also known as the bulk density, that is, ρb=W/V. This volume includes the sample itself and the sample pores and their sample interstitial volumes. P: bulk density, in g/cm3 M: sample mass, in g V: tapped volume, in cm3 (ml).     Bulk density of powder 3. Powder fluidity The flowability of powders is very important to the design of the production process. When the automatic press presses complex parts, if the powder flowability is poor, the powder loading rate of the automatic pressing cannot be guaranteed, or the phenomenon of bridging is easy to occur. The size or density does not meet the requirements, and even local can not be formed or cracked, which affects the quality of the product.     The relationship between the fluidity of powder and the angle of repose Powder flow properties are related to many factors, such as powder particle size, shape and roughness, specific surface, etc. In general, increasing the coefficient of friction between particles makes powder flow difficult. Generally, the powder flowability of spherical particles is the best, while the powder with irregular particle shape, small size and rough surface has poor flowability. 4. The angle of repose of the powder The angle of repose is the maximum angle formed by the free slope of the powder accumulation layer and the horizontal plane. Commonly used measurement methods include injection method, discharge method, tilt angle method, etc. The angle of repose can not only be measured directly, but also calculated by measuring the height of the powder layer and the radius of the disk. That is, tanθ=height/radius.     angle of repose of powder The characteristics of the powder, as well as the surface area of the powder, the porosity, and the strength of the powder, are not introduced one by one. In addition, in the powder conveying system scheme, it is necessary to know the water content of the powder, the horizontal conveying distance, the vertical conveying distance, the conveying volume per hour, etc., so when designing the pneumatic conveying scheme of the powder, it is necessary to fully Only by understanding the characteristics of the powder being conveyed can a more suitable conveying scheme be designed.