(七)造坑 为了达到“模拟钻进”的目的,必须“造坑”,即必须在井底“留下”牙齿对岩石作用后的效果。只有这样,才符合三牙轮钻头的实际工作情况,也才能得到比较接近实际的“仿真机械钻速和牙齿载荷谱”。 (VII) Construction of Pit In order to achieve the purpose of “simulated drilling”, it is necessary to “make a pit”, that is, the effect of the teeth on the rock must be “left behind” at the bottom of the well. Only in this way, it is consistent with the actual work of tri-cone bit, but also be able to get closer to the actual “simulated penetration rate and tooth load spectrum.”