地层岩心资料分析在PDC钻头设计中的应用研究

Application and Study of Formation Core Data in Design of PDC Bit

普通PDC钻头在中硬岩层中具有较好的钻进性能,而在吐哈油田鄯勒块,西山窑地层具有高硬度、高研磨性等特点,PDC钻头机械钻速低、单只钻头进尺少、耗时多,制约了PDC钻头的应用。该地层采用过特制的PDC钻头、复合钻井、扁齿牙轮钻头等多项新技术,但技术经济效益不甚明显。本文通过对岩心资料的分析,有针对性的对PDC钻头进行冠部形状及剖面设计,布齿设计,切削齿后倾角设计,现场试验证明具备较好效果。

Drilling capability of ordinary PDC bit in medium-hard layer is good,but J_2x formation in block shanle in Tuha oilfield is characteristics of high hardness and abrasiveness,so the penetration rate of PDC bit in this area is low,footage drilled per bit is little,time cost is also longer than ever,these features restrict the application of PDC bit.Many innovation techniques including special PDC bit,composite drilling,and flat tooth roller bit had been introduced into the formation, but the technical and economic benefits were not obvious.Through analyzing core data,the crown shape and cut plane design,cutters distribution design and the cogging back rake angle design are applied for PDC bits.Field application effect is good.