Cracking in aluminum gas cylinders: A review of causes and protection measures
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Cracking in a limited number of common portable aluminum gas cylinders has led to leaks and, on occasion, to violent and sometimes fatal failures. This paper describes the failure process and develops a model for crack growth. The model crack growth rates are much higher than those previously determined by small specimen testing. The levels for a threshold stress intensity below which no growth can occur are also introduced.
The inspection procedures and protection strategies for the aluminum gas cylinders are discussed. The system has become both cumbersome and possibly expensive for what it is achieving. There has been no cost benefit assessment of the entire system.
Keywordsaluminum gas cylinders cracking inspections SCUBA
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