Oxygen Analyzer Considerations

When oxygen content analysis, especially trace oxygen analysis, is performed, the oxygen content in the air is as high as 21% O2. Therefore, if the improper handling, it can easily cause pollution and interference to the sample, and the analysis result data is incorrect. The main reason is the improper operation of the oxygen analyzer. The following only discusses several factors that affect the determination of the oxygen analyzer.

1. leakage. Oxygen analyzers must be strictly leak-checked before being used for the first time. Oxygen analyzers can only obtain accurate data results without rigorous leakage. Any imperfections at any connection points, solder joints, valves, etc., will cause oxygen in the air to infiltrate into the pipeline and oxygen analyzer, resulting in a high oxygen content.

2. Pollution. When reusing the oxygen analyzer, it is first necessary to pay attention to whether or not air is leaked when connecting the sampling line of the oxygen analyzer, and the air leaked into the oxygen analyzer must be carefully blown away, and as much oxygen as possible should not be passed through the oxygen analyzer. Sensors to extend sensor life. In the purification process of the pipeline system, in order to shorten the purification time, a certain method is needed. Generally, high-pressure gas discharge and small-flow rate blowing are used to alternately purge the oxygen analyzer pipeline.

3. The choice of pipe material. Oxygen analyzer pipeline material and surface roughness will also affect the change of oxygen content in the sample gas. In general, plastic pipes, rubber pipes, etc. should not be used as connecting pipes. Oxygen analyzers usually use copper or stainless steel tubes. For ultra-micro analysis (<0.1ppm), polished stainless steel tubes must be used.

4. Gas system simplification and cleanliness. Oxygen analyzer trace analysis must effectively eliminate the contamination of the sample gas caused by dead angles in various fittings, valves, and gauges on the air line. Therefore, the oxygen analyzer gas system should be simplified as much as possible, and connectors with small dead angles should be used. Also, avoid the use of water seals, oil seals, wax seals, etc. to prevent dissolved oxygen from escaping and causing pollution. It is also necessary to avoid the addition of purifying equipment that can easily cause contamination when the sample gas is drawn to the inlet of the oxygen analyzer. Only in this way can the system be clean and the data obtained be accurate.