What are the precautions for using an experimental gradient tube furnace?

The precautions for using an experimental gradient tube furnace mainly include the following aspects:

1. Safe operation
Grounding protection: The instrument casing must be effectively grounded to ensure safe use.
Good ventilation: The instrument should be placed indoors with good ventilation, and no flammable or explosive materials should be placed around it to prevent safety accidents such as fires.
Cut off power: After using the instrument, the power should be cut off in a timely manner to prevent damage to electrical components caused by prolonged power on.
Do not collide: It is strictly prohibited for objects to collide with the machine to prevent instrument damage or safety accidents.

2. Preheating and warming up
Preheating treatment: Preheat should be carried out before use, usually at 300 ℃ for at least 2 hours, to dry the furnace of the experimental furnace, remove impurities and dry moisture.
Heating control: The heating process should be uniform and slow, strictly following the heating curve of the oven to avoid instrument damage or inaccurate experimental results caused by rapid heating. At the same time, attention should be paid to controlling the maximum temperature to not exceed the maximum operating temperature specified by the instrument.

3. Sample processing and placement
Sample requirements: It is strictly prohibited to use a resistance furnace to heat corrosive samples, flammable and explosive samples, and liquid samples. The sample should be placed in the center of the furnace tube and ensure that the tube is symmetrically placed in the center of the furnace.
Sample processing: Before placing the sample, it should be treated appropriately, such as cleaning, drying, etc., to ensure the accuracy of the experimental results.

4. Air circuit operation and inspection
Gas circuit connection: If gas is required for experiments, the gas circuit should be connected correctly to ensure that the main valve of the gas cylinder, pressure divider valve, pipeline switch, etc. are opened and closed in sequence. At the same time, attention should be paid to checking the sealing of the gas path to prevent gas leakage.
Gas flow control: Adjust the gas flow rate through the intake valve and gas circuit switch to ensure the stability and accuracy of the gas flow rate during the experimental process.

5. Instrument maintenance and inspection
Regular cleaning: Regularly clean and maintain the experimental gradient tube furnace to maintain its good condition. When cleaning, attention should be paid to avoiding the use of highly corrosive cleaning agents or tools.
Check for cracks and deformation: After each use, check for cracks in each brick, detachment of refractory lining, bending and deformation of steel frames and hangers, and deformation of furnace tubes.
Silicon carbide rod inspection: Every 3 months of use, the connection strap of the silicon carbide rod heating element should be rechecked. If it is loose, it should be re tightened. At the same time, attention should be paid to observing the use of silicon carbide rods and replacing aged ones in a timely manner.

6. Experimental records and archiving
Experimental records: Each time an experimental gradient tube furnace is used for experiments, a usage record should be carefully filled out, including information such as the experiment date, experimental conditions, and experimental results.
Archiving and Preservation: Experimental records should be archived and preserved for subsequent analysis and reference. At the same time, attention should be paid to protecting the confidentiality and security of experimental data.

In summary, the precautions for using an experimental gradient tube furnace involve multiple aspects such as safe operation, preheating and heating, sample processing and placement, gas path operation and inspection, instrument maintenance and inspection, as well as experimental recording and archiving. Only by strictly following these precautions can the safety and accuracy of the experiment be ensured, while extending the service life of the instrument.