vacuum furnace characteristics and principles
Vacuum furnace design principle
Vacuum furnace can be interpreted from a professional point of view as follows: in the chamber of this particular space, the use of vacuum systems (vacuum pumps, vacuum measuring devices, vacuum valves, furnace body, control systems and other components assembled carefully) to discharge some of the material inside the chamber, so that the chamber pressure is less than a standard atmosphere Pressure, space in the furnace chamber so as to achieve a vacuum state, in the vacuum state of an industrial furnace heated by electric heating elements, vacuum environment for heating equipment, this is the vacuum furnace.
With the continuous improvement of process quality requirements of mechanical products, vacuum heat treatment technology has been more and more widely used. The market demand for vacuum heat treatment equipment has also increased substantially. The output value and output of vacuum heat treatment equipment manufacturing enterprises have increased greatly.
The advantages of vacuum furnace are:
1) Completely eliminate the oxidation and decarbonization of the workpiece surface during the heating process, and obtain a clean surface without deteriorating layer. This has a great impact on the cutting performance of tools that grind only one side of the groove surface (such as twist drill grinding so that the decarbonized layer on the groove surface is directly exposed to the edge).
2) no pollution to the environment and no need for three wastes disposal.
3) the accuracy of furnace temperature measurement and monitoring is obviously improved. The indication value of the thermocouple reaches 1.5 degrees C. However, the temperature difference between different parts of a large number of workpieces in the furnace is large. If the forced circulation of thin gas is adopted, the temperature difference can still be controlled within the range of (?) 5 (?) c).
4) high degree of mechanical and electrical integration. On the basis of improving the precision of temperature measurement and control, workpiece movement, air pressure regulation, power regulation can be programmed and set in advance, and quenching and tempering can be carried out step by step.
5) energy consumption is significantly lower than that of salt bath furnace. Modern advanced vacuum furnace heating chamber uses high-quality insulation material made of insulation wall and barrier, can be highly concentrated in the heating chamber, energy-saving effect is remarkable.
Vacuum furnace preparation operation:
1, check whether the source of water, power, gas source is normal;
2, check whether all parts of the furnace are in normal condition.
3. Check insulation and valve should be closed.
4, the vacuum vent valve should be closed.
5. Open the main switch of the water cooling system and the stop valves of the cooling parts to check the drainage pipes to ensure the smooth flow of water and the water pressure of 0.3 Mpa. The drainage temperature should not exceed 40-50 C in furnace operation.
6. Check whether the argon system is normal, replace the air in the buffer tank in advance to achieve the required purity of argon;
7. Turn on the main power supply and check whether the indicating lights are normal.
Requirements for vacuum furnace operation:
1, when loading, ensure stable, to prevent workpiece falling, and clean the furnace door seal with ethanol.
2, during heating, water pressure, water flow and water temperature should be observed frequently. During the normal operation, no water supply is strictly prohibited. Once the water is stopped, the standby water supply system should be opened in time.
3. When the furnace is stopped, the heater will be cut off and the cooling water will continue to cool down.
4. After the workpiece is released, close the furnace door and vacuum the oven manually to keep the vacuum in the furnace.
5, regularly clean the vacuum chamber, run the high temperature washing process, and provide 1 vacuum cleaners.
6, according to the "maintenance cycle" schedule, regular maintenance.
7, operate strictly according to the operation manual.
Vacuum furnace is a device for heating in vacuum. Mainly used in ceramic firing, vacuum smelting, electrical vacuum parts degassing, annealing, brazing metal parts, as well as ceramic-metal sealing.