The cylindrical vacuum chamber is a container that keeps the inside vacuum. The vacuum chamber is made by considering the volume, material and shape.

The inner wall surface of the vacuum chamber adsorbs a large amount of gas molecules or other organic substances, and becomes a deflation source that affects the degree of vacuum. In order to achieve the vacuum requirement, the cavity should be baked at a high temperature of 150 to 250 ° C to promote the gas release on the surface and inside of the material as soon as possible. The baking method comprises winding a heating belt on the outer wall of the cavity, fixing the armored heating wire on the outer wall of the cavity or directly placing the cavity in the baking tent. A relatively economical and simple baking method is to use a heating belt, and the outside of the heating belt is wrapped with aluminum foil to prevent heat loss and uniform heating of the cavity.