What is the usual flow rate of powder feeding air? Why must it be adapted to the main airflow?

       

On the one hand, the flow rate of the powder feeding air is related to the amount of powder feeding, the fluidity of the powder and the density of the powder; on the other hand, it is related to the size of the main air flow and the arc power. If you want to send the powder into the center of the arc, the air flow should be appropriately increased. Generally, the flow rate of powder feeding air is 0.6m3/h~0.8m3/h. In addition, the proper flow of powder feeding gas should be able to send the powder into the center of the plasma flame (see Figure 6-21), so that the powder can obtain the best heat energy.

The flow rate of the powder feeding gas must be adapted to the main gas flow rate to avoid mutual interference. If the two are not properly matched, the powder bundle will not be concentrated or the nozzle will be blocked, and the nozzle and the cathode will be burned out in severe cases. . Usually, the powder feeding air flow is 1/3~1/5 of the main air flow.