Operation steps of box type vacuum atmosphere muffle furnace

The operation steps of the box type vacuum atmosphere muffle furnace are as follows:

1. Preliminary preparation and inspection:
Cleaning the environment: Ensure that the work environment is clean, free of flammable and explosive materials, and maintain good ventilation.
Equipment inspection: Check whether the electrical performance of the muffle furnace is intact, whether the grounding wire is good, and confirm that there is no power outage or leakage phenomenon. At the same time, check whether the interior of the furnace is clean, and remove any debris in a timely manner. Check the sealing of the furnace door to ensure it can be tightly closed and prevent heat leakage.
Sample preparation: Place the sample in a high-temperature resistant crucible or container, avoiding direct contact with the inner wall of the furnace. For volatile or reactive samples, pre drying or coating treatment is required.
2. Connect the power and preheat:
Connect power: Insert the power cord of the box type muffle furnace into the power socket and turn on the power switch. Some devices may require turning the electrical key 90 degrees clockwise to activate the control cabinet.
Preheating: Before formal heating, it is usually necessary to preheat the muffle furnace to ensure uniform temperature distribution inside the furnace. The preheating time is determined according to the model and specifications of the muffle furnace, and it is generally recommended to be between 30 minutes and 1 hour. During the preheating process, the initial current of the electric furnace can be gradually adjusted.
3. Set temperature and temperature rise:
Set temperature: Press the relevant button on the control panel to enter the temperature setting interface. Use the up and down keys or loop keys to adjust the temperature to the desired temperature for the experiment, and confirm the settings.
Design temperature rise and fall curves: Based on experimental requirements, design a reasonable temperature rise and fall curve. The usual heating rate should not exceed 10 ℃/minute, and the cooling rate should be below 15 ℃/minute to avoid excessive thermal shock to the furnace.
Start heating: After confirming that the temperature setting is correct and preheating is complete, press the start button or green turn on button to start the heating process. During the heating process, the furnace temperature and heating rate should be closely observed to ensure compliance with design requirements.
4. Atmosphere control and regulation:
Vacuuming: If a vacuum environment is required, first close the furnace door, turn on the vacuum pump, and start vacuuming. When the vacuum degree meets the experimental requirements, turn off the vacuum pump.
Introduction of gas: If inert gas or reducing gas needs to be introduced, after the vacuum pump is turned off, connect the gas cylinder to the inlet, open the inlet valve, and adjust the intake rate through a flow meter. Maintain a slight positive pressure inside the furnace to prevent air from entering.
5. Heating process monitoring and adjustment:
Observing the heating process: During the heating process, the furnace temperature and heating rate should be regularly observed to ensure compliance with design requirements.
Adjust parameters: To adjust the temperature or heating rate, you can press the relevant buttons on the control panel to make changes. However, please note that do not remove or insert thermocouples during high temperature conditions or use to prevent the outer casing from exploding.
6. Cooling and Sampling:
Cooling: After the heating process is completed, wait for the furnace temperature to drop to a safe range (such as below 200 ℃) before turning on the furnace. During the cooling process, it is recommended to cool naturally or follow the cooling procedure in the equipment manual to avoid forced cooling causing furnace cracking.
Sampling: Place the crucible near the furnace door to lower the temperature before taking it out for cooling. When taking out the cooling, it should be placed on an asbestos board for appropriate cooling (be careful to avoid burns), and then placed in a dryer.
7. Device shutdown and subsequent processing:
Turn off heating: After completing the experiment, press the off button or turn off button to disconnect the main circuit. Let the cooling fan inside the furnace continue to operate for a period of time to cool the furnace.
Cut off power: When the temperature inside the furnace drops to a safe range (usually ≤ 500 ℃), cut off the power switch and unplug the power cord. Some devices may require turning the electrical key counterclockwise to cut off the power supply to the control cabinet.
Cleaning and maintenance: Regularly clean the oxide and other debris in the furnace to maintain its cleanliness. At the same time, maintenance and upkeep of the equipment should be carried out, such as checking electrical performance, calibrating thermocouples, etc., to ensure its long-term stable operation.