首页>
外国专利>
Bit tool bit. The strength of the bit increases to 5.0 mm below the surface of the borehole while maintaining the hardness of the bit in this direction; procedures for increasing the strength of the bit; bit drilling tools. S and it is used to drill hard rock.
Bit tool bit. The strength of the bit increases to 5.0 mm below the surface of the borehole while maintaining the hardness of the bit in this direction; procedures for increasing the strength of the bit; bit drilling tools. S and it is used to drill hard rock.
Drill bit for ROCK DRILLING Tool, a procedure to increase the Resistance of drill bits,Rock Drill and Tool use, comprising a longitudinal cross section through a given Surface drill with relationships between hardness "L" and "H" Vick measured MethodsERS and Palmqvist.
展开▼
