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Material for Gas Flare Tip 1
- Thread starter Inchtain
- Start date
Continuous flaring, or intermittent emergency? H2S, or no H2S?
Steve Jones
Corrosion Management Consultant
All answers are personal opinions only and are in no way connected with any employer.
Steve Jones
Corrosion Management Consultant
All answers are personal opinions only and are in no way connected with any employer.
- Thread starter
- #3
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1
- #4
OK. So, the considerations are:
a) the low strength of 310(S) - UNS 31008 - the more usual flare tip grade, at temperature coupled with the continuous heat exposure that brings about detrimental microstructural changes, especially at welds. Typically, significant service periods at temperatures over 650 deg C tends to bring about early failure.
b) 800 (800H/800HT the more usual grades) is likely to be welded with 625 filler thereby immediately introducing dissimilar metal thermal response issues. Being a nickel alloy, it will be prone to sulphidation issues in H2S containing atmospheres.
Irrespective of the pros and cons of the two materials, failure analyses usually point to poor operation, and poor design, as being the main factors in premature failure. Thus it becomes a case of deciding which material will be more tolerant of the abuse that is likely to be dished out to it from design, fabrication, and operation, and, of course, which will offer the best lifecycle cost.
There are alloys, such as S38015, that are gaining a foothold in flare tip applications, and these could be worth considering.
Steve Jones
Corrosion Management Consultant
All answers are personal opinions only and are in no way connected with any employer.
a) the low strength of 310(S) - UNS 31008 - the more usual flare tip grade, at temperature coupled with the continuous heat exposure that brings about detrimental microstructural changes, especially at welds. Typically, significant service periods at temperatures over 650 deg C tends to bring about early failure.
b) 800 (800H/800HT the more usual grades) is likely to be welded with 625 filler thereby immediately introducing dissimilar metal thermal response issues. Being a nickel alloy, it will be prone to sulphidation issues in H2S containing atmospheres.
Irrespective of the pros and cons of the two materials, failure analyses usually point to poor operation, and poor design, as being the main factors in premature failure. Thus it becomes a case of deciding which material will be more tolerant of the abuse that is likely to be dished out to it from design, fabrication, and operation, and, of course, which will offer the best lifecycle cost.
There are alloys, such as S38015, that are gaining a foothold in flare tip applications, and these could be worth considering.
Steve Jones
Corrosion Management Consultant
All answers are personal opinions only and are in no way connected with any employer.
- Thread starter
- #5
Apologies, it was my typo. The alloy is S30815
Steve Jones
Corrosion Management Consultant
All answers are personal opinions only and are in no way connected with any employer.
Steve Jones
Corrosion Management Consultant
All answers are personal opinions only and are in no way connected with any employer.
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