Leakage detection and cause analysis of nitrogen hydrogen air integrated machine
1. Diagnosis of air leakage:
The flow rate of gas in a nitrogen and hydrogen air unit (hydrogen and nitrogen is indicated by the LED digital tube) is much more than the actual amount of gas. When the gas leakage is large, the flow rate is close to the rated flow rate of the generator, and the gas output pressure can not reach the rated value (generally 0.4Mpa). At this point, it can be basically identified as leakage.
2. The cause of air leakage
Sometimes it is because of the internal leakage of the nitrogen hydrogen air unit, such as the replacement of drying agent after the replacement of the drier, or the failure of the dry pipe seal ring for a long time. In most cases, the gas chromatograph itself or the gas source and the chromatograph are leaked, such as the aging of the plastic pipes, the improper connection of the joints, and the failure of the sample pad. Replacement (causing nitrogen leakage, pre column depression); vaporization chamber nozzle leakage (causing hydrogen leakage). A small amount of air leakage does not affect the use of the air, nitrogen hydrogen air unit will hear the leakage of silk when the amount of air leakage, the severe gas output pressure is not up to the rated pressure (about 0.4-0.42Mpa), at this time the nitrogen pressure can not reach the rated pressure, nitrogen flow rate is also lower than the rated flow rate (300Ml/min).
3. Inspection method of air leakage
The nitrogen and hydrogen air compressor can be used to check the joints when the air leakage is less than 100Ml/min (below). The method is: first remove the pipe which is connected with the outlet of the generator, and plug the generator outlet with the original plugging head provided by the company, observe whether the gas pressure can be restored to normal, whether the flow of nitrogen or hydrogen can return to "000", if the above two items are normal, it shows that the generator has no leakage and the nitrogen hydrogen air integral machine needs to check gas chromatography. A vaporizing chamber inlet pad, a combustion chamber nozzle, or a pipeline connected with gas source and gas chromatograph. If the outlet is blocked, the pressure and flow are still not normal, then the gas generator is checked. The nitrogen and hydrogen air machine is mainly used to observe whether the drying pipe is damaged, cracking, the sealing pad is aging, and whether there is silica gel particles in the seal.