1.
Penetration Mechanism of DTH Percussion Compact Drilling and Experimental Research on Compact Bit;
潜孔锤冲击挤密钻进机理及挤密钻头的设计与实验研究
2.
The optimization design and experimental research on percussion-compact step drill bit
阶梯式冲击挤密钻头结构优化设计及试验
3.
Field tests on pre-bored compaction lime-soil pile(down-hole dynamic compaction method) to improve serious collapsible loess
钻孔挤密桩处理强湿陷性黄土地基试验研究
4.
Design of Composite Foundation with Drilling Ram-expanded Piles in Collapsed Loess
湿陷性黄土钻孔夯扩挤密桩复合地基设计
5.
The Pore-forming Mechanism Study of Cam Bit on Percussive-Rotary Extruding DTH Drilling
凸轮型冲击回转挤压钻头成孔机理的研究
6.
Get a 121/4" Smith bit ready.
准备一个121/4"史密斯钻头。
7.
The new-type mono-metal floating seal for roller bit
牙轮钻头用新型单金属浮动密封研究
8.
unit-type drill head
组合钻床钻头, 标准钻头
9.
TEST STUDY OF A NEW TYPE NON-SEAL SLIDING BEARING CONE BIT
新型非密封滑动轴承牙轮钻头的试验研究
10.
Osculation Value Model for Diamond Bit Optimal selection and Its Application
金刚石钻头优选的密切值模型及其应用
11.
Study on Electroplated Diamond Bit for Extra-hard, Compact and Weak-abrasiveness Formation;
坚硬致密弱研磨性岩层电镀金刚石钻头研究
12.
Development and Application of Wire-line Coring Bit for Hard and Compact Rock Formation
坚硬致密岩层用绳索取心钻头的研制与应用
13.
Research Progress of the Surface Strengthening Technology on Roller Bit Metal Face Seal
牙轮钻头金属端面密封表面强化技术研究进展
14.
drill(ing) head
钻头; 主轴头; 钻床床头箱; 钻削动力头;钻头头部, 钎头
15.
part of a drill that grips the bit
夹头（钻或钻床上用以夹住钻头的部分）.
16.
a small bit that drills a first hole to guide a larger drill.
钻凿初洞来导引大钻头的一种小钻头。
17.
Theoretical Research on Mechanism of Extrudate Swell and Numeric Design of Die for Multi-Lumen Precise Medical Catheter;
多腔精密医用导管挤出胀大机理及机头数字化设计的理论研究
18.
easing the bit in
钻头轻压慢转钻进地层