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南非加尔德纳尔的邓维尔公司,试制一种摩尔牌气动冲回转钻机,能钻进直孔和30°以内的斜孔,直径为114—203毫米,可打勘探孔水上钻探和露天开采的爆破孔。钻具
Dunwell, Calif., South Africa, has trial-produced a Moor brand pneumatic recoil drill capable of drilling straight holes and slant holes of up to 30 ° with a diameter of 114-203 mm. The holes can be drilled for drilling on water and open pit mining Blast hole. Drilling tools