The oxygen bomb is the most special component in a calorimeter - it is a closed pressure vessel that can withstand a high pressure of nearly 3 MPa and contains high-pressure pure oxygen and combustion materials inside. Improper operation not only affects test results, but also poses real security risks. Clarify the operating procedures in order to protect personnel safety and ensure data reliability.
Oxygenation standard
The oxygenation pressure should be strictly controlled between 2.8 and 3.2 MPa and should not be exceeded. The HZ-384A is equipped with an oxygenation device with a pressure gauge. During oxygenation, observe the pressure gauge reading and immediately close the valve of the oxygenation device when the target value is reached.
Slow oxygenation rate - Rapid oxygenation can generate local high-speed airflow impact, which may blow away fine powder samples in the crucible, leading to ignition failure or incomplete combustion. Suggest oxygenation for 15 to 45 seconds to slowly increase the pressure.
Leak detection after oxygenation
After oxygenation, place the oxygen bomb into a basin of water and observe if any bubbles continue to emerge. If there are bubbles, it indicates that the oxygen bomb is leaking, which may be due to aging of the sealing ring or misalignment during cap tightening. At this time, it cannot be used and the sealing ring needs to be replaced or re aligned and tightened.
The situation where oxygenation is not possible
It is strictly prohibited to oxygenate crucibles or projectiles with grease on them - there is a risk of combustion and explosion when high-pressure pure oxygen comes into contact with organic matter. Before each use, it is necessary to confirm that the interior of the projectile and the surface of the crucible are clean and free of grease residue. When cleaning oxygen bombs, only water or specialized cleaning agents can be used, and organic solvents cannot be used.
Bleeding sequence
After the experiment is completed, it is necessary to slowly deflate before opening the oxygen bomb cover. HZ-384A automatically completes the water discharge operation. After the oxygen bomb is removed from the inner cylinder, slowly release the remaining high-pressure oxygen inside the bomb using the release valve of the aerator. After the pressure gauge drops to 0, unscrew the bomb cover. It is strictly prohibited to unscrew the spring cover under pressure.
Maintenance of sealing ring
The oxygen bomb sealing ring is made of rubber material, which will age and deform over long-term use, losing its sealing ability. Check the condition of the sealing ring before each use, and replace it immediately if there is deformation, cracking, or decreased elasticity (a spare sealing ring is randomly attached). Apply a small amount of Vaseline lubricant during the installation of the sealing ring to prevent tearing during tightening.
Daily cleaning of oxygen bombs
After each experiment, rinse the interior of the projectile with clean water (sulfur combustion produces acidic substances, failure to rinse will corrode the projectile), dry it, and set it aside. If there is carbon buildup on the inner wall of the projectile, use a soft cloth dipped in a small amount of alcohol to wipe it off, and do not scratch with hard objects.