Advantages And Disadvantages Of Zirconia Insert
The sampling detection method is through the guide tube, will be measured gas into the zirconium oxide test room, and then through the heating element to heat the zirconium oxide to the working temperature (750 ℃ above). Zirconium oxide is generally tubular, with porous platinum electrodes (Fig. 2). Its advantage is not affected by the detection of gas temperature, through the use of different diversion tube can detect various temperature gases in the oxygen content, this flexibility is used in many industrial online detection. The disadvantage is that the reaction time is slow; complex structure, easy to influence the detection accuracy, the sampling tube is easy to jam when the detected gas impurity is more, the porous platinum electrode is susceptible to the corrosion of sulfur and arsenic in the gas and the blockage of fine dust; the heater is usually heated with an electric stove wire, and its life is not long.Zirconia Insert
The direct-insertion test is to inject zirconia directly into the high-temperature measured gas, direct detection of the oxygen content in the gas, this detection method is suitable for detection of gas temperature at 700℃~1150℃ (special structure can also be used for 1400 ℃ high temperature), it uses the high temperature of the measured gas to achieve the operating temperature of zirconia, no need for additional heaters. The key technology of the direct-insertion oxygen probe is the high-temperature sealing and electrode problem of ceramic materials. The structure of two kinds of direct-inserted oxygen probes is listed below.Zirconia Insert
This form is from the sampling method used in the form of zirconia tube developed, that is, the original zirconia tube lengthened, so that zirconia can be directly extended to the high temperature of the measured gas. This structure eliminates the problem of high temperature seals. Because of the need to inject zirconia directly into the detection gas, the length of the oxygen probe has a high requirement, its effective length is around 500mm~1000mm, the special environment length can reach 1500mm. And the detection accuracy, the work stability and the service life all have the high request, therefore the direct-inserted oxygen probe is difficult to adopt the traditional Zirconia oxygen probe monolithic zirconia tube structure, but takes the technical request high zirconia and the alumina tube connection structure.
Sealing performance is one of the most critical technologies of this zirconia oxygen probe. Zirconia Insert
At present, the most advanced connection mode in the world, it is the permanent welding of zirconia and alumina pipe together, its sealing performance is excellent, and the method of mining style detection, straight-plug detection has obvious advantages: zirconia direct contact with the gas, high detection accuracy, rapid reaction, maintenance is small.Zirconia Insert