Acetylenes damaging mechanisms

External mechanical damage, and all dents affecting acetylene girth welds or seam welds that are known to exhibit brittle fracture characteristics, may be repaired with a full encirclement steel sleeve with ends welded to the pipe. 

CGA G-1, 5.2.1 4.2.3.2 When acetylene cylinders are moved, they should not be subjected to abnormal mechanical shocks that might damage the cylinders, the valves, or the fusible pressure relief devices. Care shall be exercised to ensure that acetylene cylinders are not dropped or permitted to strike each other violently. 

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