保压候凝对页岩气井固井质量的影响及机理分析  

Influence and Mechanism Analysis of Holding Pressure and Waiting for Solidification on Cementing Quality of Shale Gas Wells

作　　者：谭元铭 曾夏茂[1] 何鑫[1] 岳欣 方仲旗 TAN Yuanming;ZENG Xiamao;HE Xin;YUE Xin;FANG Zhongqi(Cementing Branch,SINOPEC Southwest Petroleum Engineering Co.,Ltd.,Deyan,Sichuan 618000,China)

机构地区：[1]中国石化西南石油工程有限公司固井分公司,四川德阳618000

出　　处：《石油工业技术监督》2024年第2期8-12,共5页Technology Supervision in Petroleum Industry

摘　　要：页岩气井开发过程面临钻压同步的情况,常伴有套变现象发生,影响后期压裂改造。为此,油田采取保压候凝措施预防套变。通过跟踪页岩气井保压候凝后续固井质量情况,发现采取该措施的页岩气井存在质量分界现象,即保压候凝后,在某一井深范围会出现质量反转,固井质量差异明显。通过统计数据与测井曲线图特征分析,探索总结其影响规律,并结合弹性力学厚壁筒理论对其进行了机理分析。对于抗外挤强度高的套管,在满足抗外挤条件下,不建议候凝期间采取管内保压措施。如果必须采取保压措施,建议采用弹性水泥浆、树脂水泥浆等体系进行浆体设计,并合理控制保压值以减小微间隙的产生。另外,还可在重叠段关键位置使用遇烃遇水自膨胀管外封隔器封堵气窜通道,降低后期环空带压机率。The development process of shale gas wells is faced with the situation of bit weight synchronization,often accompanied by casing deformation,which affects the later fracturing reform.Therefore,the oil field adopts the measures to keep pressure and wait for coagulation to prevent the casing change.This paper tracks the cementing quality of shale gas wells after pressure holding waiting for coagulation,and finds that there is a quality demarcation phenomenon in shale gas wells that adopt this measure,that is,after pressure holding waiting for coagulation,there will be a quality reversal in a certain well depth range,and the cementing quality is obviously different.Through the analysis of statistical data and logging curve characteristics,the influence law is summarized and explored,and the mechanism is analyzed combined with the theory of elastic thick wall cylinder.For casing with high anti-extruding strength,it is not recommended to take pressure retaining measures in the pipe during the waiting period when the conditions of anti-extruding are met.If pressure protection measures must be taken,it is recommended to use elastic cement slurry,resin cement slurry and other systems for slurry design,and reasonably control the pressure retention value to reduce the generation of micro-clearance.In addition,the gas-channeling channel can be blocked by using hydrocarbon and water self-expansion pipe external packer at the key position of the overlap section to reduce the probability of annular band pressure in the later stage.

关 键 词：保压候凝 固井质量 微间隙 预防措施 

分 类 号：TE256[石油与天然气工程—油气井工程]