big hole

Based on the field experiences and related information gathered in a quarry,the author established the technical feasibility and profitability of using large diameter drill string to quarry dimension stones on a large scale for the construction of dam surface in the hydroelectric industy.

本文根据作者在广东省怀集县高塘水电站混凝土面板堆石料的开采试验过程中的实际经验及所收集的资料，着重论述在水电行业中大规模开采混凝土面板坝堆石料的工艺中，大孔径钻具使用的技术可行性及经济合理性。

Introduced about the principles and features of ZD150 type bighole drill and discussed the main facts for influnce on the highly quality of the drill hole.

介绍了ＺＤ１５０型大孔径钻机的工作原理及高质量钻孔的特征，论述了影响高质量钻孔的主要因素。

According to Yangquan coal miningpractice, launches the application study that the great diameter perforate substituted with the trough to traverse into technology in opening, and popularizes and applies to gas drainage from adjacent layer.

针对阳泉煤业集团某矿实际,开展大直径钻孔替代顺槽横贯成孔工艺的应用研究,推广应用于邻近地层瓦斯抽放孔的施工工程中,为高瓦斯矿的瓦斯抽放寻找一种新的技术途径。

The Construction Techniques for the Deep-water and Large Aperture Drilled Piles of Hutiaomen Bridge

虎跳门特大桥深水大孔径钻孔桩施工工艺

Study on drill bit for large diameter core drilling of deep hole in hard rock

硬岩深孔大口径取芯钻进的钻头研究

Bit Design for Main Pier Bored Piles of Donghai Bridge

东海大桥主墩大直径钻孔灌注桩钻头设计

Research on the Bearing Performance of the Super-Long and Large-Diameter Bored Pile;

超长大直径钻孔灌注桩承载性能研究

EXPERIMENTAL RESEARCH ON NEGATIVE SKIN FRICTION OF LARGE-DIAMETER BORED PILES

大直径钻孔灌注桩负摩阻力试验研究

Technology of 1000 meter directional borehole at large diameter for mine gas extraction

顶板大直径千米长钻孔抽采瓦斯技术

Analysis and treatment on pile bore checking collapse accidents of large diameter bored perfusion pile

大口径钻孔扩底灌注桩在孔形检测时的塌孔分析及处理

Application of Wireless-while-drilling Technology on Large Diameter Directional Hole

无线随钻技术在大口径定向工程钻孔中的应用

Gas drainage in seam with large auto variable diameter bore holes

自动变径大直径钻孔抽放煤层瓦斯试验

guide twist drill

有导径的深孔麻花钻

Type selection of ф3.40m large diameter and deep hole drilling equipment for No 3 main tower pier of Wuhan Tianxingzhou great Yantze River bridge;

武汉天兴洲长江大桥3号主塔墩ф3.40m大直径深孔钻孔设备选型

Construction Control in Bored Pile with Big Diameter of Anqing Yangtse River Bridge

安庆长江大桥大直径钻孔桩的施工控制

Construction Technology of Large Diameter Rotary Drilled and Bored Piles in Qingdao Gulf Bridge

青岛海湾大桥大直径旋挖钻孔灌注桩施工技术

Construction Quality Control of Large-diameter Cast-in-place Bored Pile of Huanghe Bridge

黄河大桥大直径钻孔灌注桩施工的质量控制

A Developing Conceive for Bundling Pneumatic DTH Hammer of Large-diameter Cast-in place Bored Pile

发展大直径钻孔灌注桩捆绑式气动潜孔锤的一种设想

Design and Construction of large Diameter Drilling Hollow Pile without Pile Caps

无承台大直径钻孔空心桩的设计与施工

The Theoretic Research of Feasibility of Big Track Boring Used in Coal and Gas Burst Predication;

大直径钻孔预测与瓦斯突出可行性的理论研究

Study on the Vertical Bearing Capacity of Large-Diameter Bored Cast-in-Situ Long Pile;

大直径深长钻孔灌注桩单桩竖向承载性能研究