放孔 meaning in English
discharge hole
Examples
- Application for penetration of gas hole , water - discharging hole and grout hole under coal mine
适用于煤矿瓦斯抽放孔放水孔注浆孔的钻进。 - Practice and cognition of gas drainage hole construction along roof trend in fully mechanized caving coal face
综放工作面顶板走向瓦斯抽放孔施工的实践与认识