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United States Department of Transportation United States Department of Transportation

Metallurgical Evaluation of Anhydrous Ammonia Cargo Tank (Nurse Tank)

June 20, 2007

The report is result of a failure analysis and metallurgical analysis of a cargo tank (commonly known as a Nurse Tank). The Nurse Tank failed in service from a cracked head. The purpose of this project was to determine the crack initiation site (CIS) and the cause of the tank failure.

Key Words: corrosion, crack initiation site, CIS, stress, wall stress, hydrostatic, chemical analysis, metallurgical evaluation, hydraulic fluid, hydrostatically tested, initial point of fracture


If you have any technical questions not addressed by this or associated documents, contact Mark Toughiry, 202-366-4545.

Last updated: Monday, November 27, 2017