shell of boiler

例句：

1. 1.The engineer inspected the shell of the boiler to ensure it was in good condition.
   工程师检查了锅炉外壳，以确保其状况良好。
2. 2.The maintenance crew replaced the shell of the boiler with a new one.
   维修团队用一个新的锅炉壳替换了旧的。
3. 3.The shell of the boiler is designed to protect the furnace from damage.
   锅炉壳的设计是为了保护炉膛免受损害。