According to the Geological settings and the distributed laws of ore bodies and previous research results, combining with latest theories and new methods of geo
The Dabie-Sulu orogenic belt in central-eastern China is considered as a high-pressure and ultrahighpressure metamorphic belt that demensions are comparatively
The lifetime of roll-bits with inserted tooth will be obviously decreased while drilling in strata and the tungsten carbide can be integrally separated from the