pipeline start up by preheating

例句：

1. 1. The pipeline was damaged duringthe construction.
   在建设过程中管道被损坏了。
2. 2. The pipeline is essential for transportingoil and gas.
   这个管道对于运输石油和天然气至关重要。
3. 3. The pipeline has been shutdown due to safety concerns.
   由于安全担忧，这个管道已经关闭了。