How to choose a vacuum drying oven?

The vacuum drying oven is specially designed for drying heat-sensitive, easily decomposable and easily oxidized substances. It can flush inert gas into the interior, especially some items with complex components can be quickly dried.


First of all, from the perspective of structure, the drying oven shell is generally made of cold-rolled steel plate, but the thickness is quite different. Due to the vacuum environment in the vacuum drying oven, in order to prevent the atmospheric pressure from damaging the oven, the thickness of the shell is slightly larger than that of the blast drying oven. Generally, the thicker the steel plate is, the better the quality and the longer the service life. In order to facilitate observation, the door of the drying oven is equipped with glass windows. Usually there are tempered glass and ordinary glass on the inlaid door. It is better to use tempered glass. Although the price is slightly higher, its  appearance is beautiful and it is more safe for operators as a strong guarantee. From the outside to the inside, there are two choices for the inner tank of the drying oven, one is galvanized sheet, and the other is mirror stainless steel.


Galvanized sheet is easy to rust during long-term use, which is not conducive to maintenance; mirror stainless steel has a neat appearance and is easy to maintain with a long service life. It is a high-end liner material on the market, but the price is slightly higher than that of galvanized sheet. The sample rack of the inner tank generally has two layers, which can be added according to customer requirements. Since the sample rack is made of stainless steel, and the additional racks are not conducive to the internal hot air circulation, and the quality requirements of the fan are increased.


Secondly, when it comes to temperature, we have to talk about heat preservation and sealing. At present, the main insulation materials of domestic drying ovens are fiber cotton, and a few use polyurethane. The different characteristics of the two materials are as follows. In terms of heat preservation effect, polyurethane has better heat resistance and heat insulation effect than fiber cotton. Generally, polyurethane can keep the high temperature in the oven stable for a few hours. It is worth mentioning that the good heat insulation performance of polyurethane can effectively to prevent the operator from being burned due to excessive temperature outside the oven. When the drying oven made of fiber cotton is at high temperature, it can only be controlled and adjusted continuously by the temperature controller to keep the stable temperature in the oven, which greatly increases the working intensity of the fan and the controller, thereby shortening the service life of the drying oven. In terms of post-maintenance, since polyurethane is injection molded into the oven body, post-maintenance is particularly cumbersome. It is necessary to take out all the polyurethane before repairing, and then inject it in after repair. The fiber cotton is comparatively not so troublesome and simple to operate. Finally, from the market, the fiber cotton is very cheap, and can meet most of the thermal insulation requirements, so it is widely used. Professional advice: the thinner the fiber cotton, the greater the thickness, and the higher the insulation quality. The sealing of the drying oven  is generally made of anti-aging silicone rubber, and the sealing effect is very good.


In terms of circulating heating performance, the choice of fans is very important. There are mainly domestic and imported fans. The professional choice is mainly imported French technology, low-noise and high-performance fans, which will not produce the noise like domestic fans during use, and have good circulation effects and fast heating. Of course, choice can also be made according to customer needs.