摘要
以地层特性为依据有针对性地选择PDC异形齿,可以降低其失效的概率并提高其机械钻速和进尺。为了综合对比脊形PDC齿的机械性能和破岩效果,对165斧形、135斧形、三刃3种脊形PDC齿的耐磨性能和抗冲击性能进行测试,随后选择花岗岩进行3个吃入深度的单齿切削试验和不同压力下的全尺寸钻头模拟钻进试验,并与普通圆形齿的结果进行对比。结果表明:3种脊形PDC齿的耐磨性能均优于圆形齿的;165斧形齿与三刃齿的抗冲击性能优于圆形齿的,而135斧形齿的冲击点缺少材料支撑,其抗冲击性能较差。在相同吃入深度下,脊形齿的切向力与法向力均低于圆形齿的相应力,且脊角越小切削力越小。135斧形齿的机械钻速最快且适合高钻压;与165斧形齿比较,三刃齿在≤20.0 kN的低钻压下机械钻速较快,在>20.0 kN的高钻压下机械钻速较慢;圆形齿的机械钻速最慢,所适合的钻压也较低。同时,当脊形齿的脊角变化时,其冲击点的材料支撑也发生改变,进而影响其抗冲击性能;且脊角变化会改变前方岩石内部的应力集中,进而改变其破岩效果。
Objectives:With the depletion of easily recoverable oil reservoirs,the focus of oil and gas exploration and development in China has shifted to"two deeps and non-conventional"oil and gas fields.This transformation is not only accompanied by a significant increase in well depth and more complex formation challenges but also presents more stringent requirements for the design and construction of drilling engineering,which directly leads to a significant extension of the drilling cycle.The length of the drilling cycle is a key factor in determining drilling costs.Therefore,for a long time,scholars have been committed to improving the mechanical penetration rate and the durability of polycrystalline diamond composite(PDC)bits.The main purpose of this study is to analyze geological characteristics in depth,accurately match and optimize the design of special-shaped teeth in PDC drill bits,in order to significantly reduce the risk of drill bit failure and greatly improve mechanical drilling speed and footage.Given the wide application of PDC bits in hard rock drilling and their key impact on the cost and efficiency of drilling operations,this study focuses on the design and optimization of ridge-shaped PDC teeth,aiming to explore more suitable tooth structures for specific geological conditions through scientific testing and comparative analysis.This will promote innovation and efficiency improve-ments in drilling technology.Methods:Based on round teeth,the wear resistance,impact resistance,and rock-breaking effect of three types of ridge-shaped teeth were systematically tested.First,the wear resistance and impact resistance of three typical ridge-shaped PDC teeth−namely the 165 axe-shaped,135 axe-shaped,and three-edged cutters−were tested to quantitatively evaluate their mechanical properties.Subsequently,granite was selected as the representative rock sample,and the single-tooth cutting tests were conducted with three different penetration depths to simulate the cutting effect under various drilling pressures duri
作者
谢志涛
赵宇璇
郭勇
吴德胜
李亚东
XIE Zhitao;ZHAO Yuxuan;GUO Yong;WU Desheng;LI Yadong(Research Institute of Engineering Technology,PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China)
出处
《金刚石与磨料磨具工程》
CAS
北大核心
2024年第5期599-606,共8页
Diamond & Abrasives Engineering
关键词
PDC钻头
异形齿
脊形齿
机械性能
破岩效果
PDC bit
special-shaped teeth
ridge-shaped teeth
mechanical property
rock-breaking effect
