When the high-pressure steam sterilizer is in use, the cold air in the sterilizer must be exhausted. Because the expansion pressure of air is greater than that of water vapor, when water vapor contains air, the pressure shown on the pressure gauge is not the actual pressure of water vapor, but the sum of water vapor pressure and air pressure.
Because under the same pressure, the temperature of steam containing air is lower than that of saturated steam, so when the sterilizer is heated to the required sterilization pressure, if it contains air, the required sterilization cannot be achieved in the sterilizer If the temperature is too high, the sterilization effect will not be achieved.
Classification of autoclaves
There are two types of high-pressure steam sterilizers: down-row pressure steam sterilizers and vacuum pressure steam sterilizers, and down-row pressure steam sterilizers include portable and horizontal types.
(1) The lower-row pressure steam sterilizer has double exhaust holes in the lower part. During sterilization, the density of cold and hot air is different, and the hot steam pressure on the upper part of the container forces the cold air to be discharged from the bottom exhaust holes. When the pressure reaches 103 kPa ~ 137 kPa, the temperature can reach 121.3°C-126.2°C, and sterilization can be achieved within 15 min ~ 30 min. The temperature, pressure and time required for sterilization are adjusted according to the type of sterilizer, the nature of the item, and the size of the package.
(2) The pre-vacuum pressure steam sterilizer is equipped with an air vacuum pump. Before the steam is introduced, the interior is evacuated to form a negative pressure, so that the steam can easily penetrate. At a pressure of 206 kP and a temperature of 132 °C, it can be sterilized in 4 min -5 min.
