钻眼用的钎头直径选择是否合理,对钻眼速度、爆破效率、炸药消耗、掘进成本都有影响。钎头直径是按药卷直径决定的,习惯要求钎头直径比药卷直径大5～7毫米。目前国家定型生产的药卷直径有32、35、38毫米3种,钎头直径则有36、38、40、43、46毫米等多种。我们煤矿常用药卷直径为35毫米,常用钎头直径为43毫米。据现场实用观察,钻眼直径经常比钎头直径大1～2毫米 Drill hole with the drill diameter choice is reasonable, the drilling speed, blasting efficiency, explosive consumption, tunneling costs have an impact. Drill diameter is determined by the diameter of the drug roll, used to drill diameter than the diameter of the coil 5 to 7 mm. The current state of the stereotypes of the drug roll diameter 32,35,38 mm 3 kinds of bit diameter 36,38,40,43,46 mm and other. Our coal commonly used drug roll diameter of 35 mm, commonly used bit diameter of 43 mm. According to the site of practical observation, the drill diameter is often larger than the diameter of the drill 1 to 2 mm