Why is nitrogen used for the gas-tightness test of spherical tanks? Can compressed air be used instead?
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Why is nitrogen used for the gas-tightness test of spherical tanks? Can compressed air be used instead?
This post was last edited by ylb913 on 2018-7-14 at 13:36. Our company’s nitrogen is available in 2.4 MPa and 0.7 MPa pressures, while the purified air has a pressure of only 0.5 MPa (the designed value being 0.6 MPa). When it comes to spherical tanks, liquefied gas is the first thing that comes to mind. The saturated pressure inside such tanks is usually around 10–20 kilograms per square centimeter. In this case, it’s relatively simple to carry out pressure testing using nitrogen at 2.4 MPa; there’s no need to remove air after the testing, as doing so would require increasing the pressure again.
Nitrogen is generally used because: 1. Nitrogen, after purification, is clean and dry and free of moisture； 2. Nitrogen is an inert gas and does not oxidize ； 3. Compressed air contains a high amount of moisture, which can easily cause the storage tanks to rust. 4. Compressed air is dirty and can contaminate the tanks.