DIN EN 12007-4-2012 天然气基础设施.最大使用压力小于等于16 bar的管道.第4部分:修复管道的专用功能要求.德文版本EN 12007-4-2012
Gas infrastructure - Pipelines for maximum operating pressure up to and including 16 bar - Part 4: Specific functional requirements for renovation; German version EN 12007-4:2012