drill adapter

After an analysis of the 3D stress field on a Model CD350 drill pipe elevator, the stress intensity factors(SIFs) of the surface corner crack with different depths and shapes on the critical section are worked out by the finite element displacement method, and the pattern of variation of SIFs along the front of the crack is presented.

对ＣＤ３５０钻杆吊卡三维应力场进行了分析，进而采用有限元位移法求解危险截面处不同深度和不同形状表面角裂纹的应力强度因子。

Research on Technology of Fast Speed Drill Pipe Bit Based on Breaking Roadway Floor Ore-forming

基于破碎巷道底板成孔的快速钻杆钻头技术研究

hard banding of tool joint

钻杆接头表面加硬圈

hard facing of tool joint

钻杆接头表面加硬层

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

unit-type drill head

组合钻床钻头, 标准钻头

Analysis on balling up caused by helicoid hydraulic motor bypass valve failure in combined drilling technology

复合钻井过程中螺杆钻具旁通阀刺漏造成钻头泥包分析

According to the drillpipe structural characteristics, a dolly appropriate for drillpipe and Kelly detection is designed, of which its probe is adjustable.

根据钻杆的结构特点,设计了探头距离可调的适用于圆钻杆和方钻杆的探测小车。

Threads on rotary shouldered connections for petroleum industry

GB/T9253.1-1999石油钻杆接头螺纹

Petroleum equipment--Thread gages for rotary shouldered connections

GB/T4749-1993石油钻杆接头螺纹量规

Longitudinal-cracking Failure Analysis of Box

φ139.7mm钻杆内螺纹接头纵向开裂失效分析

Cause Analyses of Pin Joint Fracture of 139.7 mm Heavy Weight Drill Pipe

139.7mm加重钻杆外螺纹接头断裂原因分析

Failure Analysis on Tool Joint Expansion of φ88.9mm×9.35mm G105 Drill Pipe

φ88.9mm×9.35mm G105钻杆内螺纹接头胀扣失效分析

Finite element analysis of the screw structure of the drill-stem junction

钻杆接头螺纹结构形式的有限元分析

Its main functions are maintaining borehole gage,improving drill string stability and protecting lower drill string from excessive wear.

其重要作用是保持钻头尺寸符合标准，提高钻杆稳定性，避免钻杆下部过于磨损。

part of a drill that grips the bit

夹头（钻或钻床上用以夹住钻头的部分）.

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。

easing the bit in

钻头轻压慢转钻进地层