In order to solve the drilling bit jammed,drilling bit buried,low drilling cuttings discharging,serious gas outburst,low mechanization level and others occurred when the conventional drilling rods applied to the borehole drilling in the medium soft seam or coal and gas outburst seam,a new triangular drilling rod was researched and developed.
为了解决传统钻杆在中软煤层或煤与瓦斯突出煤层顺层钻孔时的卡钻、埋钻、排渣效率低、瓦斯突出严重、机械化程度不高等问题,采用了使钻杆形成3个半圆形的间隙,扩大排出煤粉和瓦斯的通道,随着钻杆边的搅动,钻渣被压力风悬浮起来,同时在风量、风速的作用下向孔口传输运移,据此研制了新型三棱钻杆,根据丁集矿的大量试验,对已应用的三棱钻杆的不足之处进行了改进,结果表明,三棱钻杆在中软煤层顺层抽排瓦斯钻孔施工中能够高效成孔。
Application of Triangular Drilling Rod to Gas Drainage Borehole Drilling in Medium Soft Seam
三棱钻杆在中软煤层顺层瓦斯抽排钻孔的应用
prismatic compass
棱镜罗经，三棱镜罗盘仪
Agrobacterium-Mediated Transformation of Malus Robusta with Rirol Gene;
农杆菌介导三价融合基因（Rirol）转化八棱海棠的研究
an oblique a regular, a right, a triangular ] prism
斜正、直、三角]棱柱
an oblique [ a regular, a right, a triangular ] prism
斜[正、直、三角]棱柱
The Design and Research of the Three Stations Vertical Injection Equipment for Rubber Stator of Screw Drill and Screw Pump and Simulation of 3D Dynamic Process;
螺杆钻具和螺杆泵橡胶定子的三工位立式注射成型设备的设计研究与三维动态模拟
great lengths of drill pipe which are rotated by an engine at the top,
钻杆顶部安装的发动机带动钻杆旋转，
a prism whose bases are triangles.
底面是三角形的棱柱。
A prism disperses light.
三棱镜可使光色散。
hard banding of tool joint
钻杆接头表面加硬圈
Ingersoll-Rand jumbo column
英格索尔－兰德钻车托杆
stacking capacity of derrick
井架的钻杆立根容量
plain clinometer
钻杆下部装的测斜仪
hard facing of tool joint
钻杆接头表面加硬层
engine ,drill, dental, with swivel arm
牙科钻机,带旋转杆
shoulder dressing tool
钻杆接头端面整形工具
Defects Analysis on 37CrMnMo4 Drill Pipe Joints
37CrMnMo4钻杆接头缺陷分析
5.11 The drill collar O.D. is 7.5 inch, and the drill pipe O.D. is 5 inch.
钻铤外径为7.5” ，钻杆外径为5敗£