Ask X3What does 49 CFR 178.60 (Specification 8AL steel cylinders with porous fillings for acetylene) require?
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As a motor-carrier owner, here is what 49 CFR 178.60 requires for Specification 8AL steel cylinders with porous fillings for acetylene:
* Type and Service Pressure: They must be seamless steel cylinders with a service pressure of 250 psig. Heads may be attached by welding, brazing by dipping, or a welded circumferential body seam (longitudinal seams are prohibited).
* Steel and Identification: The steel used must match Table I of Appendix A to the part, and plates and billets for hot-drawn cylinders must be marked with a heat number.
* Manufacture: Cylinders must be made with proper equipment to ensure they conform to the rules, have no weakening defects, and possess a reasonably smooth finish. Welding procedures and operators must be qualified using CGA Pamphlet C-3.
* Footrings: Exposed bottom welds on cylinders longer than 18 inches must have protective footrings.
* Welding and Brazing: All welding or brazing is prohibited except for attaching specific parts (like neckrings, footrings, handlers, bosses, pads, and valve-protecting rings) made of weldable steel with a carbon content of no more than 0.25 percent.
* Wall Thickness and Stress: Calculated wall stress at 750 psi cannot exceed 35,000 psi or half of the steel's minimum ultimate strength (whichever is smaller). For cylinders with an outside diameter over 5 inches, the minimum wall thickness must be 0.087 inches.
* Heat Treatment: Every cylinder must be uniformly and properly heat-treated above 1,100 °F prior to testing, and after all forming and welding operations. Liquid quenching is not allowed.
* Openings: All openings must feature standard taper pipe threads that are clean-cut, even, without checks, and tapped to gauge.
* Pressure Testing: Each cylinder must successfully pass pressure testing according to strict lot-testing rules (testing at least one random cylinder out of a lot of 200 or less to a minimum of 750 psig, while remaining cylinders are proof-tested between 500 and 600 psig).
* Leakage Testing: Cylinders with bottoms closed in by spinning must undergo a leakage test using interior air or gas pressure set to at least the service pressure.
* Physical Testing: Physical tension tests must be performed on two longitudinal specimens cut from a randomly selected cylinder out of each lot of 200 or less, following heat treatment.