is the core drill bit is a figwork or a bristle (the water drill is the silk or the anti-wire)

所谓绳索取芯钻杆是一种不提钻而能取得岩芯所使用的钻杆 绳索取芯钻杆的特点是“三高一低”，即钻速高金刚石钻头寿命长时间利用率高，工...