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Beefy Backpack Tree Marking Paint System
Technical Support Documents High Temperature Exposure of Aluminum Cylinders August 10, 2000 DOT 3AL and DOT 4E aluminum cylinders subjected to fire must be removed from service according to section (f) (4) of CFR 49 part 173.34 titled Qualification, Maintenance, and Use of Cylinders. No testing for acceptance or re-heat treatment is authorized. In CGA pamphlet C-6.1; Standards For Visual Inspection of High Pressure Aluminum Gas Cylinders, it states that cylinders heated to metal temperatures in excess of 350° F (176° C) must be condemned. Common evidence of exposure to elevated temperatures that may heat the metal temperature to 350° F (176° C) include: charring, blistering, or discoloration of the cylinder paint or protective coatings; distortion of the cylinder; melting of non-metallic (i.e. plastic, etc.) valve components; charring or burning of labels; activation of valve pressure relief device; or activation of the heat indication system. Catalina Cylinders recommends that if there is evidence, or it is believed, that a cylinder has been exposed to elevated temperatures but the temperature of metal of the cylinder is not believed to have reached 350° F (176° C) for any duration of time, the cylinder must still be subjected to hydrostatic testing or condemned. A cylinder that has been exposed to temperatures great enough to change the temper of the cylinder could show an increase in total or permanent expansion as measured during hydrostatic testing. Cylinders showing unusually high total expansion or exceeding the regulatory limits for the relationship of permanent expansion to total expansion (i.e. DOT = 10% and TC = 6%) should be condemned. In CGA pamphlet C-6.1; Standards For Visual Inspection of High Pressure Aluminum Gas Cylinders, it states that cylinders heated to metal temperatures in excess of 350 oF (176° C) must be condemned. Common evidence of exposure to elevated temperatures that may heat the metal temperature to 350° F (176° C) include: charring, blistering, or discoloration of the cylinder paint or protective coatings; distortion of the cylinder; melting of non-metallic (i.e. plastic, etc.) valve components; charring or burning of labels; activation of valve pressure relief device; or activation of the heat indication system. Catalina Cylinders recommends that if there is evidence, or it is believed, that a cylinder has been exposed to elevated temperatures but the temperature of metal of the cylinder is not believed to have reached 350° F (176° C) for any duration of time, the cylinder must still be subjected to hydrostatic testing or condemned. A cylinder that has been exposed to temperatures great enough to change the temper of the cylinder could show an increase in total or permanent expansion as measured during hydrostatic testing. Cylinders showing unusually high total expansion or exceeding the regulatory limits for the relationship of permanent expansion to total expansion (i.e. DOT = 10% and TC = 6%) should be condemned. |
 
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