Thread wear and damage are normal expectations during the service life of a cylinder. External threads particularly are subject to damage, as shown in this photo. Per the stipulations of 49CFR Part 180.212, CP Industries as a cylinder manufacturer, working under supervision of an independent inspection agency, is authorized to perform re-threading of DOT and UN specification containers. CP Industries is also authorized to perform similar work on ASME vessels under the terms of our ASME “R” (repair) stamp. These capabilities can dramatically extend cylinder service life.