Analysis of advantages and disadvantages of external vacuum heat treatment furnace

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The advantages of external vacuum heat treatment furnace are:

1. Simple structure, easy to construct, or modified with original normal heat treatment resistance furnace;

2. The vacuum chamber volume smaller, less displacement, furnace tank in addition to the work piece, there are few other need to gas components, and thus put less gas (no insulation panel structure, etc.), easy to achieve high vacuum;

3. Since the electric heating element is heated externally, there is no vacuum discharge problem;

4. There are no more mechanical operation of the furnace, simple operation, less failure and convenient maintenance.

5. The workpiece of the high temperature vacuum furnace is not in contact with the lining of the furnace, and there is no possibility of chemical action at high temperature;

6. Compared with the internal heat vacuum furnace, due to its simple structure and equivalent load, the cost is only 1/2 to 1/3 of the internal heat vacuum furnace; From maintenance, service life and reliability evaluation, more practical.

However, there are some defects in thermal vacuum heat treatment furnace.

1. The heat transfer efficiency of the furnace is low, and the heating speed of the workpiece is slower.

2. The furnace tank material, furnace temperature is generally maintained at below within the range of 1000-1000 ℃;

3. Part of the furnace can be exposed to the atmosphere, although the insulation screen can be set, the heat loss is still very large.

4. The heat capacity and thermal inertia of the furnace are large, and the control is difficult.

5. The service life of the furnace can be short.

vertical gas quenching furnace