Does the vacuum drying oven need to be vacuumed or heated first?

The role of the vacuum drying oven.
Vacuum drying oven is specially designed for drying heat-sensitive, decomposable and oxidizable substances, and it is able to flush inert gas into the interior, especially for some items with complex composition, which can be dried quickly.



Using areas.
Scope of application: Vacuum drying oven is widely used in biochemistry, chemical and pharmaceutical industry, medical and health care, agricultural research, environmental protection and other research applications, for powder drying, baking, and various types of glass containers for disinfection and sterilization only. It is especially suitable for drying heat-sensitive, easily decomposed, easily oxidized substances and complex ingredients for rapid drying treatment.

Vacuumed or heated first?
1 ) If it is operated according to the procedure of heating and then vacuuming, when the heated air is pumped out by the vacuum pump, the heat will be brought to the vacuum pump, which will lead to too high temperature rise of the vacuum pump, and may cause the efficiency of the vacuum pump to drop and damage the vacuum pump.

2 ) The heated gas is directed to the vacuum pressure gauge, and the vacuum pressure gauge will generate temperature rise. If the temperature rise exceeds the specified operating temperature range of the vacuum pressure gauge, it may cause the vacuum pressure gauge to show value error. The correct way to use the gauge is to draw vacuum first and then heat up the gauge. After the rated temperature is reached, if the vacuum degree is found to have decreased, then pump it appropriately. This is beneficial to extend the service life of the equipment.

3) The workpiece is put into the vacuum box to draw vacuum in order to draw off the workpiece material can be drawn off the gas composition. If the workpiece is heated first, the gas will expand when exposed to heat. Since the vacuum box is very well sealed, the enormous pressure generated by the expanding gas may cause the tempered glass of the observation window to burst. This is a potential danger. This danger can be avoided by following the procedure of vacuuming before heating.

So when we use the vacuum drying oven to heat, we must draw vacuum first before heating.