Inspectioneering

Integripedia Topic
Amine Stress Corrosion Cracking (SCC)

Explore this topic

Amine Cracking is a form of stress corrosion cracking, which is related to alkaline and carbonate stress corrosion cracking. Amine cracking is often intertwined with wet hydrogen sulfide (H2S) and carbonate cracking, as amines, carbonates and wet sulfides often exist together in amine treating systems. Amine cracking typically occurs on the surface and the cracks are usually radially projected from set-on nozzles. Because of this, most properly applied methods of surface nondestructive examination (NDE) will find the cracks.

Postweld heat treatment (PWHT) is an effective means of mitigating amine cracking, so this affliction is most commonly associated with equipment handling lean amine solutions that has not been stress relieved or may have been inadequately stress-relieved. That would include contactors, absorbers, strippers, regenerators and accumulators as well as any equipment that is subject to inadvertent amine carry over or steam cleaning in preparation for maintenance. Though cracking is most often associated with non-stress relieved weldments (especially the Heat Affected Zone), it can also affect non-stress relieved base metals that have been cold worked and not been subject to PWHT. Examples include bent pipe/tube, knuckle region of formed heads, and formed plate.

Amine cracking is more prevalent in MEA and DEA systems, but can also occur in MDEA, DIPA, and ADIP systems. Critical causal factors include stress level, temperature, and amine concentration. Though cracking has been reported under some circumstances at ambient temperatures, it is more prevalent with increasing temperatures, depending upon solution concentration. API RP 945 (R2008), Avoiding Environmental Cracking in Amine Units, 3rd Edition provides guidance on PWHT of equipment to avoid amine cracking. One should also note that austenitic stainless steels and alloy 400 are resistant to amine cracking. Since cracks are normally surface breaking, most properly applied methods of surface NDE will find the cracks, though liquid penetrant testing (PT) may miss tight-fine amine cracks.

Related Topics

Topic Tools

Share this Topic

Contribute to Definition

We welcome updates to this Integripedia definition from the Inspectioneering community. Click the link below to submit any recommended changes for Inspectioneering's team of editors to review.

Contribute to Definition
Articles about Amine Stress Corrosion Cracking (SCC)
January/February 2005 Inspectioneering Journal

Amine cracking is a form of stress corrosion cracking, which is related to alkaline and carbonate stress corrosion cracking. Amine cracking is often intertwined with wet H2S and carbonate cracking, as amines, carbonates and wet sulfides often exist...

Authors: John Reynolds
Partner Content

Download Pinnacle's Economics of Reliability Report - Refining to see how reliability is affecting profitability.

    Downloads & Resources related to Amine Stress Corrosion Cracking (SCC)
      News related to Amine Stress Corrosion Cracking (SCC)
        Partner Content

        LOTIS utilizes laser profilometry to conduct internal steam reformer tube inspections. The data captured by LOTIS is exceptionally powerful when combined with our LifeQuest™ remaining life assessment capabilities, providing an integrated...


        Inspectioneering Journal

        Explore over 20 years of articles written by our team of subject matter experts.

        Company Directory

        Find relevant products, services, and technologies.

        Talent Solutions

        Discover job opportunities that match your skillset.

        Case Studies

        Learn from the experience of others in the industry.

        Integripedia

        Inspectioneering's index of mechanical integrity topics – built by you.

        Industry News

        Stay up-to-date with the latest inspection and asset integrity management news.

        Blog

        Read short articles and insights authored by industry experts.

        Expert Interviews

        Inspectioneering's archive of interviews with industry subject matter experts.

        Event Calendar

        Find upcoming conferences, training sessions, online events, and more.

        Downloads

        Downloadable eBooks, Asset Intelligence Reports, checklists, white papers, and more.

        Videos

        Watch educational and informative videos directly related to your profession.

        Acronyms

        Commonly used asset integrity management and inspection acronyms.