double safety valve

例句：

1. 1. The double safety valveprevents the system from overheating.
   双安全阀防止系统过热。
2. 2. The engineer double-checked all thesafety valves before the launch.
   工程师在发射前检查了所有的安全阀。
3. 3. Thedouble safety valve is essential for maintaining asafe working environment.
   双安全阀对于保持一个安全的工作环境至关重要。