Liquid ammonia storage tanks must be heat treated after welding
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Do liquid ammonia storage tanks need to be heat treated after welding? Why?
Carbon steel and low alloy steel are subject to stress corrosion, so post-weld stress relief heat treatment should be performed.
GB150th 10.4.1.2 The article stipulates that containers with stress corrosion marked on the drawing, such as liquid ammonia, must be heat treated.
Liquid ammonia is a moderately hazardous medium and has a tendency to corrode, so it should be heat treated. This post was last edited by Lan Meng on 2009-2-21 08:43 ]
Carbon steel or low alloy steel containers containing liquid ammonia are subject to stress corrosion according to GB150 10.4.1.2 , so post-weld heat treatment should be carried out
Liquid ammonia is a moderately hazardous medium and is corrosive.； According to GB150 10.4.1.2 The drawing indicates containers with stress corrosion, such as containers containing liquefied petroleum gas, liquid ammonia, etc.
Liquid ammonia is generally a low-temperature container and should undergo stress-relieving heat treatment.
It should depend on the use situation and materials used. If it is made of Q235-C and liquid amine storage tanks are used in the refrigeration industry, there is no need for heat treatment. Liquid amine storage tanks in other industries are based on GB150 10.4.1.2 Vessels with stress corrosion indicated in the drawing shall undergo post-weld heat treatment.
It is not necessary to do overall heat treatment. Although it is filled with liquid ammonia, there may not be stress corrosion. Because liquid ammonia may cause stress corrosion, the following two conditions must be met at the same time.: 1. The medium is liquid ammonia, the water content is not high, usually -5°.
Agree with the 9th floor’s opinion, there are conditions for stress corrosion of liquid ammonia on HG20581
It should be heat treated unless it is under low temperature and low stress conditions.
If the material is stainless steel, does it also need to undergo stress relief heat treatment?