Key points for attention before and after operation of high-temperature annealing furnace

1, Before drying the high-temperature annealing furnace, measure the resistance between the electric heater and the furnace shell using a meter. Short circuits are not allowed. After drying, use a 500V meter to measure the cold break current resistance of the electric furnace. The resistance value shall not be less than 0.5moh. Before using a resistance furnace, it is necessary to check the power connector, power cord, and the overall circuit for current interruption.
2, The stove should be kept clean regularly, and debris such as iron oxide should be cleaned after work. Cleaning should be carried out after cutting off the power and reducing the furnace temperature.
3, Using explosive gas furnaces or emitting harmful gases, heating gas furnaces should have safety devices or other health measures.
4, The electric part or transmission device outside the furnace shell should be equipped with a protective cover. To ensure the operation of the annealing furnace system, safety devices should be installed.
5, Regularly check if the automatic power-off device for opening and closing doors is in good condition to avoid electric shock accidents. When loading and unloading products, do not touch the electric heater to avoid accidents when the automatic power off device malfunctions. When the working voltage of the annealing furnace exceeds 36 volts, there should be a good grounding device.
6, The automatic temperature control device can ensure that the ignition wire is correctly heated according to the specified heating wire. Therefore, it is important to pay attention to the normal operation of the measuring instruments for heating gas stoves.
7, Precautions for drying machine:
1. Check the tightness of all pipelines in the high-temperature annealing furnace, prepare a dew point meter and oxygen analyzer, check the working status of the combustion system, temperature control system, and thermometer, check whether the cooling water of each heat exchanger and household roller system is working properly, and carry out ignition and temperature rise according to the operating specifications of the combustion system.
2. When the furnace temperature rises to 150 ℃, add crude nitrogen to the furnace and follow the process requirements.
3. When the furnace temperature rises to 200 ℃, the furnace rollers enter a low-speed crawling state to prevent bending and deformation of the furnace rollers.
4. When the furnace temperature rises to 400 ℃, the fast cooling fan is put into low-speed operation.
5. When the furnace temperature rises to 500 ℃, stop adding coarse nitrogen to the receiving room and start adding fine nitrogen. Execute the process according to the process requirements and measure the oxygen content inside the furnace.
6. When the furnace temperature rises to 700 ℃, the oxygen content in the furnace is less than 200ppm. When the furnace pressure is dry positive pressure, a 5% hydrogen nitrogen mixture can be sent into the furnace and the flow rate can be increased sequentially according to the process requirements.
7. When the furnace temperature rises to 800 ℃, inject the hydrogen nitrogen mixture with normal production flow into the annealing furnace, and open the dew point meter to measure the dew point inside the furnace. A dew point between -25 ℃ and -45 ℃ is considered qualified. If it is not qualified, it will be sold to the oven.
8. After the high-temperature annealing furnace reaches the standard for drying, cooling begins. When the temperature drops to 650 ℃, stop hydrogen injection and blow with fine nitrogen gas. When the hydrogen content in the furnace is less than 0.4%, open the threaded hole for thread processing.