I have measured the oxygen level in my continuous furnace, and it's low, but my parts still come out oxidized. Why?
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Don Bowe Sr. Applications Engineer |
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Guido Plicht Senior Research Engineer Europe |
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This is a question that comes up frequently. When troubleshooting for oxidation in a continuous furnace atmosphere, it's important to measure both oxygen level and dew point. Here's why.
The dew point is a measure of the moisture content of a gas and is the temperature at which water vapor in a sample gas starts to condense. Oxygen concentration is simply that—a measure of the partial pressure of oxygen.
When a gas sample is extracted from the hot zone of a furnace for analysis, reactive gases like H2, CO, or CxHy have already combined with any O2 present to produce moisture and other gaseous components. As a result, depending on the furnace temperature and how the sample is obtained, your analyzer will often display a low oxygen level. In most applications, a low oxygen level and a low dew point are required to control the process and prevent oxidation.
Click here to find the Gas Atmosphere Analysis Guidelines For further details contact Shawn Lainchbury tel: +44 (0) 1932 249 398
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