In the process of water supply and drainage treatment, various chemical agents are often added for coagulation, flocculation, coagulation aid, disinfection and sterilization to achieve the purpose of water purification. These drugs come in solid particles, liquids, and colloids, and must be dissolved, diluted, and quantitatively added in proportion during the dosing process to achieve optimal results. So the dissolving drug dosing device is one of the commonly used equipment in water treatment engineering.