The hydrogen embrittlement problem in stainless steel
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1. Which is more prone to hydrogen embrittlement, carbon steel or stainless steel? 2. Currently, the medium is hydrogen at a pressure of 3 MPa and at room temperature; the measuring instrument used is a vortex flow meter made entirely of 316 material. Is it necessary to apply NACE treatment to this vortex flow meter in order to prevent hydrogen embrittlement? 3. Which is the main factor causing hydrogen embrittlement: temperature or pressure? 4. I searched for some information online, but it all only explained what hydrogen embrittlement is and how to reduce the hydrogen content in steel; it didn’t mention in what situations hydrogen embrittlement occurs. I am from a instrumentation manufacturer and lack knowledge of actual field applications. I hope that those of you with experience can share what they have seen in terms of field installations for measuring the flow rate of hydrogen or other media containing H2S – were stainless steel instruments used in such cases? What are the temperature and pressure? Has there been a problem with hydrogen embrittlement? Has it been treated with NACE? Very g
Same question: how is NACE treatment carried out?
Similarly curious, waiting for the expert to provide an answer
”At room temperature, hydrogen does not cause significant corrosion of steel. However, when the temperature is between 200 and 300 degrees and the pressure is 30 MPa, hydrogen diffuses into the steel, where it reacts chemically with cementite to form methane. This process leads to decarburization of the steel, as well as the formation of numerous grain boundary cracks and bubbles, thereby significantly reducing the steel’s toughness and causing severe embrittlement. Therefore, for the situation described in the question – where the medium is hydrogen gas at a pressure of 3 MPa and at room temperature – a vortex flow meter made entirely of 316 material can be used without any special treatments.
For instruments, to prevent hydrogen embrittlement in the liquid-contacting parts, the best approach is to use a thin layer of gold plating. Under normal circumstances, when the operating temperature exceeds 200°C or the pressure exceeds 3.5 MPa, the effect of hydrogen embrittlement must be taken into account.
At room temperature, consider hydrogen embrittlement at a few bar pressure. Just as the sun shines on your bare bottom, that little sprout below your navel won’t catch fire either. . . :Is a P hydrogen gas cylinder just an iron lump? It does make a crisp sound – how could such an iron lump be used as a pressure vessel! Moreover, once the gas cylinder is in use, it lasts for decades.
3.5MPa is nonsense. . . The hydrogen cylinder is at a proper pressure of 15 MPa.
Some kids, coming from terrorist families, like to scare people :P.
At these pressure and temperature levels, stainless steel instruments can be used just fine; however, the pipelines are likely to be made of carbon steel for the most part……
Temperature has a greater impact than pressure, because of the greater kinetic energy of molecules； Also, look up more papers for research questions