Effect of Hole Length on Long-Hole Drilling Performance

Bibliographic Information

Other Title
  • 長尺さく孔におけるさく孔深さの影響
  • チョウシャク サクコウ ニ オケル サクコウ フカサ ノ エイキョウ

Search this article

Description

In this study, systematic in-situ tests along Suzuka tunnel were carried out to examine the drilling performance in case of drilling holes up to 50 m depth. Special care was taken to clarify the effect of hole length on drilling performance such as penetration rate, rotational torque and oil pressure applied to the rock drill.<BR>Results can be summarized as follows;<BR>1) Averaged penetration rate has a declining trend with increase of hole length. Energy of elastic wave is gradually decreasing while propagating rods. Averaged decrease of penetration rate was 1.5% per 3 m-length rod.<BR>2) Averaged penetration rate fluctuated especially at 20m and 40m of hole length. It was considered that an interaction between piston movement and reflected wave from the bit caused this considerable amount of fluctuation.<BR>3) Rotational torque has an increasing trend with increase in hole length and frictional resistance between drill rod and hole.

Journal

  • Shigen-to-Sozai

    Shigen-to-Sozai 120 (3), 146-151, 2004

    The Mining and Materials Processing Institute of Japan

Citations (5)*help

See more

References(22)*help

See more

Details 詳細情報について

Report a problem

Back to top