molten metal flame spraying

例句：

1. 1. The molten metal was sprayedinto the furnace to heat up the entirebuilding.
   熔化的金属被喷射进炉膛以加热整个建筑。
2. 2. The molten metal flame sprayingis a dangerous operation that requiresspecial training.
   熔化金属火焰喷射是一项危险的操作，需要特殊的培训。
3. 3. The moltenmetal flame spraying was used to repairthe damaged roof of the old house.
   熔化金属火焰喷射被用来修复旧房子受损的屋顶。