1. Water bath

Water bath is a hot bath method that uses water as a hot bath substance. Since the water temperature is 100 ℃ at the standard atmospheric pressure, the maximum temperature of the water bath is 100 ℃. The method of using water bath to treat container products is: immerse the container requiring water bath in the larger container containing water, and the container requiring water bath shall not be in direct contact with the larger container. Then place the larger container on the heat source to heat, stop heating when it reaches the appropriate temperature, and take out the water bath container after cooling.

2. Oil bath

Oil bath is a hot bath method that uses oil as a hot bath substance. Commonly used oils include soybean oil, cottonseed oil, etc. The maximum temperature of oil bath is higher than that of water bath, generally between 100 ℃ - 250 ℃. The operation method of oil bath is the same as that of water bath, but the operation of oil bath should be especially careful to prevent oil overflow or high temperature rise of oil bath, which will cause fire.

Temperature difference: water bath temperature 0-100, oil bath temperature 100-260.

Heating process: during heating, the material to be heated is usually placed in the container, and the container is placed on the heat source. If some containers, such as glass containers and ceramic containers, are directly placed on the heat source, they often explode due to uneven heating, rapid temperature rise, or uneven heating of the heated material due to poor heat transfer. Therefore, the heating container products entering the laboratory should be treated with hot bath. The so-called hot bath is to place the container in the hot bath material, let the temperature of the hot bath material rise slowly to a certain extent, and then let it cool slowly, so as to improve the heat transfer performance of the container and make the bottom of the container uniform. The commonly used hot bath methods in the laboratory include water bath, oil bath, sand bath, etc.