How to select materials for sulfur-containing media?
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Question: How do experienced users choose materials for sulfur-containing media?
Can stainless steel be used in sulfur-containing media?
For sulfur-containing media, ordinary carbon steel is sufficient; using stainless steel is too costly. The acidic gas line of our sulfur recovery unit contains 70-80% hydrogen sulfide, and it is made of 20# steel
Reference can be made to the material requirements for stress-corrosion-prone environments outlined later in the specifications; currently, 20R is commonly used. Stainless steel is too expensive.
What sulfur is it containing? Sulfur, or hydrogen sulfide, or maybe other things like sulfur dioxide? Maybe I can help you look into it
In a hydrogen sulfide environment, when using stainless steel, the issue of stress corrosion must be taken into account; in addition, problems such as hydrogen-induced cracking and hydrogen bulging also need to be considered!
It is necessary to analyze each specific case individually; it is important to specify what kind of medium is involved, as well as the pressure and temperature levels, as well as the sulfur and water content, in order to make a determination. In principle, the requirements outlined in the relevant regulations should be followed.
The use of carbon steel and low-alloy steel in wet H2S stress corrosion environments must meet the following requirements: 1. The yield strength δs specified in the material standards shall be ≤ 355 MPa； 2. The actual measured tensile strength σb of the material ≤ 630 MPa ； 3. The material should be in at least a normalized or normalized+tempered state, an annealed state, or a conditioned state ； 4. Carbon steel equivalent limit (when the carbon equivalent limit is exceeded, the monitoring frequency of the hardness limit should be increased) ； Low-carbon steel and carbon-manganese steel: CE≤0.40, where CE=C+Mn/6. Low-alloy steel (including low-temperature nickel steel): CE≤0.45, where CE=C+Mn/6+（Cr+Mo+V）/5+（Ni+Cu）/15. Refer to HG20581-1998
Carbon steel will do; it also depends on the specific circumstances.
For media in which stress corrosion may occur, either 16MnR or 20R can be used
Excuse me? What kind of sulfur is it – elemental sulfur, or hydrogen sulfide? Is it dry hydrogen sulfide or wet hydrogen sulfide?