在砂砾层及风化岩层，采用硬质合金钻头施工钻孔灌注桩时，若所克取的岩砂粒较大，不易排出孔外，只有经过重复破碎，最后成为小粒径的岩砂才能随泥浆排出孔外。这就增加了硬质合金刀片的消耗，直接影响工程的经济效益。为了解决上述问题，我公司制成四翼式取砂硬质合金钻... In the gravel layer and weathered rock layer, the use of hard alloy bit construction bored piles, if the grit larger grabs, difficult to discharge holes, only after repeated crushing, and finally become the small size of the rock sand to mud Out of the hole. This increases the consumption of carbide inserts, a direct impact on the economic benefits of the project. In order to solve the above problems, our company made four-wing sand hardened carbide drill ...