| 摘要 |
The present invention relates to a drilling bit capable of easily installing a steel pipe by using a wing bit which can be folded. The drilling bit includes: a bit body having a cutting edge excavation surface on one side and a guide groove on the other side; the wing bit having a shaft protrusion, which can be guided along the guide groove of the bit body, on one side or both sides and rotating around the shaft protrusion guided along the guide groove by being assembled with the bit body; a stopper member installed in the bit body to prevent the shaft protrusion from being separated from the guide groove; and a wing bit fixing device installed in the bit body and/or the stopper member and fixing the wing bit so that the wing bit can be fixed in a state that the wing bit is pivoted and spread in a moving direction. |
