绳索取心钻进中,特别是深孔钻进,岩层变化复杂,某一钻头不可能对多种岩层都具有良好的适应性.在某些较硬且研磨性弱的地层中钻进,往往会出现人造孕镶金刚石钻头的“抛光”和“打滑”现象,时效极低.对于这种现象,以往常采用砂轮打磨法或酸腐蚀法使钻头金刚石重新出刃,以改善钻头进展状况.但这两种方法都必须把钻头提出地表,因而造成大量时间的浪费,且对钻头的破坏作用也较大,特别是砂轮打磨法.这里向大家介绍一种坑道钻现场曾经用过的投砂研磨法. 投砂研磨法,不需将钻具提离孔底,而是在钻头出现抛光或进尺很慢的情况下,将砂粒由孔口投入孔底进行研磨钻进,使金刚石出刃.操作过程如下:首先,在地表选择一些较为坚硬的岩块,把岩块砸成碎粒状,粒径约4～6毫米;在内管提取上来之后,将 Coring in ropes, especially in deep holes, complicates rock formation, and a drill bit can not be well adapted to a wide variety of formations, and drilling in some harder and less abrasive formations often There will be artificial impregnated diamond bit “polishing” and “slippage” phenomenon, the very low aging.This phenomenon, the wheel grinding or acid etching method used to make the drill bit diamond to re-edge, to improve the bit progress .But this Both methods must be put on the surface of the drill bit, resulting in a lot of time wasted, and the destruction of the drill is also greater, especially the grinding wheel method. Here to introduce a tunnel drilling site used sand grinding method Sand casting grinding method, without lifting the drill from the bottom of the hole, but the bit appears polished or footage is slow, the sand from the hole into the bottom of the hole for grinding and drilling, the diamond out of the blade. : First, select some of the more hard rock on the surface, the rock smashed into pieces, the size of about 4 ~ 6 mm; after the extraction of the inner tube will be