Vacuum Sealed Quartz Tube Operation Instructions

Before starting the sealing process, carefully inspect the equipment for faults. Ensure all sealing valves are closed, and check the acetylene and oxygen levels. If refilling is needed, verify if the high-pressure Ar (argon) is depleted. If both the equipment and gas cylinders are in good condition, proceed with the following steps:

Select the appropriate quartz tube, sleeve, and sealing ring.

Turn on the main power switch (G1) and the mechanical pump switch (G2). Slowly open valve V4. Once the low vacuum gauge (right-side dial) shows a reading of less than 5 Pa, close V4.

Slowly open valve V1. Once the low vacuum gauge reading stabilizes, turn on the molecular pump switch (G3). When the reading stabilizes, open valve V2. You can also turn on the high vacuum gauge (left-side dial) to monitor the vacuum level. When the vacuum level reaches the sealing requirement (generally below 10^-5 Pa), begin the sealing process.

Close valves V2 and V1, open the Ar gas cylinder, and adjust valve V3 to fill the gas. When the gas flow meets the requirements, close V3 and the cylinder.

Open the acetylene and oxygen cylinders. Before ignition, purge any residual air from the pipes. Slightly open the acetylene switch (red knob) on the nozzle and ignite.

Alternate the adjustments of the acetylene and oxygen switches (blue knob) to achieve the desired flame.

Once the flame is adjusted, proceed with the required sealing operation.

After sealing, alternately close the acetylene and oxygen switches, closing the acetylene switch last until the flame is extinguished. Close the acetylene and oxygen cylinders and purge any residual gases from the pipes. Close valves V2 and V1, and remove the quartz tube for the next sealing operation (repeat steps 1-7).

After all experiments are completed, securely close valves V4, V3, V2, and V1. Sequentially turn off G3, G2, and G1. Clean the workspace and record the experiment details.

1. Ensure the quartz tube is clean and dry to prevent contamination of the molecular pump by moisture or debris.
2. Maintain a sealing distance of more than 15 cm from the joint to avoid high-temperature damage to the sealing gasket.
3. Operate the molecular pump valve V2 cautiously during experiments; direct atmospheric entry into the molecular pump is strictly prohibited to prevent alarms and pump damage.
4. Vacuum levels are influenced by atmospheric conditions. If the required vacuum level is not achieved over time, consider heating the molecular pump and moderately baking the quartz tube and pipes, avoiding excessive temperatures to prevent hazards.
5. After ignition, avoid directing the flame toward the acetylene, oxygen hoses, or other surrounding objects to prevent explosions.
6. Post-experiment cleanup is essential, ensuring all gas cylinders, valves, and power sources are off, and experiment records are maintained.
7. Adherence to these rules is mandatory; violations leading to accidents will be held accountable.
8. For any questions, contact the equipment manager.

1. To prevent flame drift during the sealing process, close the windows, but open them after venting the pipes to avoid residual acetylene and oxygen in the room.
2. Calculate the safe gas filling volume to avoid overfilling, which can complicate the sealing process and pose annealing hazards.
3. In case of a sealing leak during the experiment, promptly close the molecular pump valve V2, if conditions permit, to prevent sudden gas influx and pump blade damage.
4. If the operator is absent during gas extraction, place warning signs to prevent others from breaking the glass tube and causing atmospheric entry into the molecular pump. If the glass tube is accidentally broken, promptly inform the sample owner to discuss solutions.
5. If the equipment is not in use after sealing, place an empty glass tube and draw it to low vacuum before shutting down to maintain the vacuum system’s cleanliness.
6. Avoid prolonged operation of the high vacuum ionization gauge.

GlobalQT specializes in manufacturing high-quality quartz tubes and quartz tube heaters, providing customizable solutions at reasonable prices. For more information, visit our website or contact us via email at contact@globalquartztube.com.