莺琼盆地塑性泥岩地层钻井提速技术  

Technologies to increase ROP for plastic mudstones,Ying-Qiong Basin

作　　者：李云龙 杨海东 杨骏师 LI Yunlong;YANG Haidong;YANG Junshi(Engineering Technology Zhanjiang Branch,CNOOC Energy Development Co.Ltd.,Zhanjiang,Guangdong 524057,China)

机构地区：[1]中海油能源发展股份有限公司工程技术湛江分公司,广东湛江524057

出　　处：《天然气勘探与开发》2024年第2期81-88,共8页Natural Gas Exploration and Development

基　　金：中海油能源发展股份有限公司工程技术湛江分公司项目(编号:20216372)。

摘　　要：南海西部莺歌海及琼东南盆地是南海高温高压气田主要分布地区,该区域高压储层上部是一大套泥岩盖层,具备强塑性特征,加上高密度钻井液的压持效应,导致钻头切削齿难以吃入地层,机械钻速缓慢。通过系统总结近年来针对该区块大套塑性泥岩采取的3种主要提速技术,从钻井液体系及比重优化、钻头优化、钻井参数优化及配套提速工具等方面,提出一套适用于莺琼盆地塑性泥岩地层钻井提速技术。应用结果表明:①莺琼盆地塑性泥岩的提速可以通过减弱井底压持效应、增强对塑性泥岩的切削效率来实现;②使用优化钻头+配套提速工具+优化钻井液体系及密度的综合提速技术可以实现良好提速效果;③马达及超级马达在较软地层钻进提速明显,但砾石等研磨性强的地层对钻头损伤较大;④水力脉冲及扭冲工具均有较好效果,水力脉冲工具更适用于东方区块埋深相对较浅的高压井的提速,对于埋深较深、地层压力系数极高的地层,应用液力提速马达的效果更加明显。There are high-temperature and high-pressure(HTHP)gasfields mostly in Yinggehai-Qiongdongnan(Ying-Qiong)Basin,west of the South China Sea.A massive set of mudstones in this area,as caprock underlying high-pressure reservoirs,enjoys strong plasticity.And there is another chip hold effect from high-density fluids,leading to hard drilling of bit cutters and slow rate of penetration(ROP).So,three existing approaches to increase this ROP were summed up for the plastic mudstones.And then,some innovative ROP-increasing technologies also available for this kind of rocks in Ying-Qiong Basin were proposed in terms of optimizing the drilling fluids,mud weight,bits,drilling parameters,and supporting tools.Results show that(i)mitigating the chip hold at bottomhole or enhancing the cutting efficiency in the mudstones may upgrade the ROP;(ii)the optimized bits matched with increasing tools as well as the preferable fluids and mud weight may achieve better ROP;(iii)motors or supermotors can help significantly improve the ROP in softer formations whereas serious damage to the bits in highly abrasive rocks such as gravels;and(iv)both hydraulic pulse and torsional impact tools work well in this increase.The former is more suitable for high-pressure wells targeting relatively shallow formations in eastern basin,while hydraulic motors are more effective for those in deep formations with extremely high pressure.

关 键 词：南海 高温高压 塑性泥岩 钻井 提速技术 

分 类 号：TE52[石油与天然气工程—油气田开发工程]