To always ensure the high accuracy of a bored hole without depending on workers experience and intuition.
Test boring is carried out to a depth not attaining designed depth prior to real boring, and in the case of the test boring, a boring rod 2 having a boring information measuring device which can measure a present boring position is applied to a rod tip part to carry out a boring work. The value of an unknown parameter in an estimating common formula is set up on an actual measured value obtained in this case at each depth position and a hole bend estimating common formula so that both the above values may be similar for deciding a hole bend estimating curved formula under specified boring conditions. In the case where the alteration of boring conditions is judged to be necessary, the boring condition parameters are properly altered under the hole bend estimating curved formula, and the boring curve in the case of real boring is simulated to decide the final boring conditions in the case of the real boring, and then the real boring is started under this boring condition.
IMAOKA HIKOZO
YOSHINAGA MASAO
MURAKAMI SOJI
TAKATSUKA MASAHIKO
