| 摘要 |
PROBLEM TO BE SOLVED: To provide a deviation amount measurement device for a drilling bit, capable of minimizing the time required for corrective drilling by exactly grasping a tip position of a drilling bit and confirming a tendency of hole bentness in an initial stage of the hole bentness. ! SOLUTION: A deviation amount measurement device for a drilling bit connected to a tip of a drilling rod and drilling a hole in a subsoil includes: a measurement device body 1 installed on a top edge of the drilling rod 30 when drilling is suspended; a striate body 13 provided to be suspended from an upper part of the measurement device body 1 and inserted into the drilling rod 30; a guide member connected to a tip of the striate body 13, ascending/descending in the drilling rod, and holding a part connected to the striate body always at a center of the drilling rod; and sensors 20a, 20b, 21a, 21b provided in the measurement device body 1 and detecting plane coordinates positions of the striate body 13 at a set heigh |
