This standard specifies the basic parameters, technical requirements, test methods, inspection rules and signs, packaging, transportation, storage, etc. of steel welded gas cylinders. This standard applies to refillable low-pressure liquefied gas and its mixture with compressed gas, which are used at normal ambient temperature -40°C to 60°C, with a hydraulic test pressure of not more than 12MPa (gauge pressure) and a nominal volume of 1L to 1000L. cylinders. This standard is also applicable to the cylinders of industrial liquefied petroleum gas and dissolved acetylene gas cylinders that are repeatedly filled as specified in GB 11174.