If you smell gas or see a broken line, shut off the main valve from the outside.
如果闻到煤气味儿，或看到管道破裂，要关掉从外面进屋煤气管道的主阀门。
2
When a natural gas network is done off-line numerical simulation, every pipeline needs be distributed initiatory flow as the initiatory value of iterative computation.
在对天然气管网进行离线数值模拟计算时，需要给各管段分配初始流量，并作为迭代计算的初始值。
3
Compared with traditional off-line and other on-line detection technologies, optical imaging technology is a great breakthrough in the SF6 gas leakage detection.