backing pump,vacuum forepump,fore-pump,forvacuum pump是什么意思

用法例句

To seek the technique method for mining the thick seam in high gas and outburst mine safely and effectively,experimental researches are carried out on the laws of gas emission coal roadways such as protective seam,protected seam and beforehand drainage seam while excavating in the thick seam at the same area in high gas and outburst mine,and the causes are anslyzed.

研究结果表明:采用大面积预抽煤层瓦斯的方法可以有效降低煤层瓦斯含量、保证巷道掘进安全。

Application of confirmation model for reasonable pre-draining time is introduced in this paper.

主要介绍了合理预抽期确定模型在焦作矿区的应用。

Technology of gas pre-drainage with deep borehole pre-cracking blasting for gateway rapid excavation in seam with outburst;

突出煤层快速掘进深孔预裂爆破预抽瓦斯技术