Maintenance and maintenance of vacuum furnace

1. The furnace body, instruments and control cabinet should be kept clean at all times.

2. Do not store flammable and explosive materials within 2m of the furnace.

3. The surface paint of the furnace shell shall be kept intact and painted regularly.

4. When the furnace temperature is higher than 400. 12, the furnace door shall not be opened for a long time.

5. The operating temperature must not exceed the rated temperature of the furnace.

6. Regularly repair and improve the sealing measures of the furnace mouth.

7. Lubricate the mechanical transmission parts regularly.

8. Regularly check whether the graphite heater terminal is clamped and tighten it in time.

9. Do not bring corrosive substances and moisture into the furnace for heating.

10. Once the graphite heaters are connected to each other, they should be separated in time after power off.

11. Regularly remove the residual oxide scale and other impurities at the bottom of the furnace.

Maintenance of vacuum furnace

Re-calibration of the heating power of the vacuum furnace. With the extension of the furnace use time, the thermal resistance of the heat shield becomes smaller, the electric heating element volatilizes and the resistance becomes larger, and the power should be appropriately increased. In the actual production work, the power is generally determined by empirical calculation method. Figure 4-15 shows the graph of the relationship between the volume of the graphite felt or refractory fiber felt heat shield vacuum furnace and the heating power. According to this figure, 1300 can be determined. C's vacuum furnace heating power. If it is a vacuum furnace with a metal heat shield, the found heating power needs to be increased by about 30%.

Maintenance of heat shield The heat shield plays a role of heat insulation and heat preservation in the vacuum furnace, and is sometimes used as the structural basis of the fixed heater. There are generally four types of heat shield structures: all-metal heat shields, sandwich heat shields, graphite felt heat shields and mixed felt heat shields. The main points of different heat shields should be mastered during maintenance.

All metal heat shields generally use molybdenum and tungsten materials in the 1-2 layers close to the heating element, and the outer layers can be stainless steel materials, and the thickness should be as thin as possible (medium and small furnaces are generally 0.2. The large furnace is 0.5～1.0mm); the surface of the heat shield needs to be processed into a smooth state before assembly to reduce the blackness and enhance the reflection effect. 1300. The number of heat shields of furnace C is generally 5-6 layers, and the distance between layers is 5-10mm. The contact area of ​​several layers of radiant board connection should not be too large to reduce thermal short circuit. The heat shield should have expansion and contraction, and be made detachable to facilitate next maintenance.