• Categories:News Center
• Time of issue:2022-05-06 10:38

(Summary description)In the industrial production process, pneumatic conveying powder is one of the important processes. Due to the special properties of powder, accidents such as fire and explosion occur occasionally during pipeline transportation. The generation of static electricity is one of the important reasons. This article will talk about the causes and prevention of static electricity in pneumatic pipeline conveying powder.   During the pipeline transportation of powder, a large amount of static electricity is easily generated after violent collision and friction between powder and powder, powder and pipe wall, and it is difficult to eliminate. Static electricity can easily agglomerate the powder and cause sparks, thereby affecting production and even causing potential safety hazards. The main factors that affect the generation of static electricity in the conveying process are: 1. Material influence Experiments show that if the powder is the same as the pipe material, the amount of static electricity generated is less; when a pipe made of metal material is used for transportation, the amount of static electricity generated has almost nothing to do with the type of metal material of the pipe; and when the pipe and the powder are insulated. When the material is used, the material properties have the greatest influence on the amount of static electricity, and can even change the sign of the static charge. 2. Time influence The longer the powder is transported in the pipeline, the more times the powder particles collide with the pipeline, and the amount of static electricity on the surface of the particles also increases. However, long-term transportation also increases the chance of charged particle discharge, that is, the amount of static electricity generated at the beginning increases with time, but after a period of time, it gradually tends to be saturated.   3. The influence of powder conveying speed When the powder conveying speed is faster, the friction and collision are more intense, the static electricity generated is more serious, and the time required to reach saturation is also greatly reduced. In the process of pneumatic conveying, if the airflow speed is as high as several meters per second, the static electricity will soon reach a saturation state, which will seriously affect the production. 4. The influence of powder particle size From the point of view of single particle, large particles are more charged than small particles, but as a whole, under the condition of constant mass, the smaller the powder particle, the larger the total surface area of the particle, the more charged, so the smaller the powder is. The greater the amount of static electricity generated.   5. The influence of the shape and structure of the powder conveying pipeline The shape of the pipe, the bend radius, and the smoothness of the inside of the pipe wall all have an effect on the generation and accumulation of static electricity. Studies have shown that bent pipes are more prone to static electricity than straight pipes, and narrow pipes are more prone to static electricity than wide pipes. According to the influencing factors of static electricity, in the process of pneumatic conveying, by controlling the conveying speed of the powder, adjusting the size of the powder particles, etc., the possibility of the occurrence of static electricity is minimized and the occurrence of static electricity hazards is prevented. On the other hand, static elimination equipment such as ion tubes and static eliminators can be installed in the pneumatic conveying system to eliminate or reduce the static electricity of materials in the pipeline.