For bedrock drilling ordinary hard alloy driller can be adopted for vertical core-drilling with the addition of clear water during rotation. for overburden dry drilling process can be adopted.

基岩钻探方法以采取普通硬质合金清水回转垂直取心钻进，覆盖层采用干钻。

youdao

For bedrock drilling ordinary hard alloy driller can be adopted for vertical core-drilling with the addition of clear water during rotation. for overburden dry drilling process can be adopted.

基岩钻探方法以采取普通硬质合金清水回转垂直取心钻进，覆盖层采用干钻。

youdao