因为空气中或多或少都含有水蒸气，当空气被空压机压缩后，水蒸气就会变成液态水污染腐蚀储气筒和各类泵阀，在冬天的时候还有可能造成泵阀结冰，引发刹车失灵，所以就需要在空压机和储气筒之间的管路上，安装一个干燥罐来吸附空气中水分。
Because the air contains more or less water vapor, when the air is compressed by the air compressor, the water vapor will become liquid water pollution and corrode the air reservoir and all kinds of pump valves. In winter, it may cause the pump valves to freeze, causing brake failure. Therefore, it is necessary to install a drying tank on the pipeline between the air compressor and the air reservoir to absorb the water in the air.