easing the bit in

easing the bit in

钻头轻压慢转钻进地层

bit-pinching formations

钻压略重就扭矩增大转速减慢的地层

4.14 Drilling with cone (drag) bit in the section.

此段地层采用牙轮（刮刀）钻头钻进。

Application of Roller Bit Combination Drilling Technology in Nappe Strata of Qingxi Oilfield

牙轮钻头复合钻进在青西推覆体地层的应用

Drilling with cone( drag) bit in the section.

此段地层采用牙轮（刀）头钻进。

tension-control cylinder

控制钻头给进的液压缸

Design optimization of PDC bit based on core information of volcanic layer

基于火山岩地层钻井岩心资料的PDC钻头设计改进

Development of the software on the diamond bit type selection according to formation rock property

根据地层岩性进行金刚石钻头选型的软件开发

Study on matrix performance of iron-based diamond bit and drilling tests

热压铁基金刚石钻头胎体性能及钻进试验研究

Drilling is performed with a rotating tool called a drill.

钻孔是用一个称为“钻头”的旋转刀具进行的。

AN APPLICABLE METHOD FOR ESTIMATION OF FORMATION DRILLING STRENGTH AND BIT WEAR

地层抗钻强度与钻头磨损实用评估方法

The Development of the Light Hydraulic Driven Coring Drill and Tools for Soft Sediment;

轻便型松散（软）地层原状取心全液压钻探机具的研制

DISCUSSION OF TECHNOLOGY FOR DISPLAYING THE BORE STRATA HISTOGRAM IN-PHASE WITH DRILL

钻进时同步显示钻孔地层柱状图技术探讨

Start collaring with reduced throttle to the impact mechanism and feeding, let the bit work its way slightly into the rock.

开孔时，应采用最小的冲击和推进力，使钻头平稳地进入岩层。

Application of Monitoring Formation Pressure while Drilling in Western Sichuan Basin

川西地区地层压力随钻监测方法应用

Research on Hydraulic Feed System for PDC Test Equipment

PDC钻头试验装置进给液压系统研究

The paper sequentially analyzed the starting-crack mechanism of hydraulic fracture bore which lies in coal delamination or lies between two coal delaminations or through many coal delaminations.

进而论文分析阐述了煤分层中钻孔、分层层面钻孔、以及穿层钻孔水力压裂的起裂机理。

near-bit-influx detector

近钻头地层流体浸入检测器