Put the medicinal materials to be extracted into the extraction tank, and add a certain proportion of solvents such as water,ethanol, methanol, acetone, etc. according to the production process (add it according to the process). For the extraction of the original medicine, the extraction temperature can be set according to actual needs. The extraction is carried out according to the production process. After the extraction is completed, the pipeline valves are opened in sequence, and the liquid is pumped into the concentration tank for concentration. The temperature of the concentrated liquid is set at the required value, and the vacuum degree is maintained at -0.05 to -0.09MPA. The secondary steam generated during the concentration passes through the condenser and cooler to become the condensate and return to the extraction tank as a new solvent. Add the new solvent to the medicine. From top to bottom, through the medicinal material layer to the bottom of the extraction tank, the soluble components in the medicinal material are dissolved in the solvent in the extraction tank, and sent to the extraction tank as a new solvent, forming a new solvent and refluxing extraction until it is completely dissolved (the extract is colorless) and the concentration continues. ,Until it is concentrated into the required specific gravity ointment, the colorless liquid in the extraction tank can be reused next time.