電圧印加方式による岩石穿孔に関する研究
1967 年 83 巻 953 号 p. 1071-1076
詳細
1967 年 83 巻 953 号 p. 1071-1076
In this study, the physical and mechanical properties of the specimen were examined at first in connection with the electrical disintegrating drilling and then some experiments were carried out to determine how effectively the electrical disintegrating drilling can be used in comparison with a conventional rotary drilling. The specimen used throughout this study was the cement mortar. The main results obtained can be summarized as follows:
1) Both the strength and the Young's modulus of the cement mortar decreased greatly by cooling it rapidly after it had been heated over 300°C.
2) When the voltage applied on the bit was larger than 750V, the effect of electrical disintegration appeared remarkably and the rate of penetration in these cases reached 1.7-2.0 times larger than that obtained by a conventional rotary drilling under the identical condition.
3) For this method of drilling, the bit having a self-sharpening action was considered to be more effective than the cutting type one.
4) To get the effective drilling with the tri-cone bit, the electrical energy beyond 3 KWS had to be spent per unit length of penetration.
