论述了用于井下巷道工作面等处照明开关的防爆性。

This puper expounds explosion-proof property of lighting switches used in underground tunnel working area etc.

youdao

论述了用于井下巷道工作面等处照明开关的防爆性。

This puper expounds explosion-proof property of lighting switches used in underground tunnel working area etc.

youdao