塔中區(qū)塊二開井段鉆井復雜情況原因分析與對策研究
發(fā)布時間：2019-02-20 07:31
【摘要】：為了減少塔中區(qū)塊二開鉆井復雜,本文綜合運用室內試驗和鉆完井資料,對二開鉆井兩大主要問題三疊系PDC鉆頭泥包和二疊系井壁失穩(wěn)的原因進行了分析,并提出了相應的對策。主要研究內容和研究結果如下：(1)通過展開室內試驗,對三疊系和二疊系地層泥巖巖心進行了粘土礦物組分、理化性能和微觀結構分析。試驗表明,紫紅色泥巖的高粘土含量和強分散性是造成PDC鉆頭反復泥包的原因；褐色泥巖高粘土含量和強分散性是造成褐色泥巖水化坍塌的客觀條件；灰色泥巖存在大量微孔、晶間孔、層理縫加劇了水化,使得這段粘土含量不高的井段出現(xiàn)井壁失穩(wěn)。(2)通過縱波時差計算了密度和橫波時差,并且計算了區(qū)塊二疊系地層巖石力學特性參數(shù)、上覆巖層壓力和地層孔隙壓力、水平地應力的大小,為后續(xù)研究提供了基礎數(shù)據(jù)。計算結果表明,二疊系泊松比為0.30-0.37,彈性模量為7000-35000MPa,抗拉強度為3-13MPa,粘聚力為3-30MPa,內摩擦角為20-35。；地層上覆巖層壓力當量鉆井液密度為2.20-2.22g/cm3,地層孔隙壓力當量鉆井液密度為1.05-1.10g/cm3,最大水平地應力分別為2.35-2.55 g/cm3,最小水平地應力為2.00-2.20 g/cm3左右。(3)從力學的角度評估井壁穩(wěn)定,分析井周應力分布狀態(tài),建立了基于Mohr-Coulomb強度準則的地層坍塌壓力和破裂壓力預測模型,計算了地層坍塌壓力和破裂壓力剖面。研究結果表明,二疊系坍塌壓力最高達到1.45 g/cm3,較高的坍塌壓力和相對較低的鉆井液密度之間矛盾是井壁失穩(wěn)的力學原因；破裂壓力在1.70-1.90 g/cm3之間。(4)對三疊系PDC鉆頭泥包,進行了優(yōu)選排量、使用鉆井液清潔劑的對策研究,對二疊系井壁失穩(wěn),進行了鉆井液密度設計和鉆井液抑制劑優(yōu)選的對策研究。研究表明,減少泥包應加強區(qū)塊清潔劑使用管理,鉆井液排量在21.59cm井眼中應達到33L/s,在24.13cm井眼中達到42 L/s；二疊系井段鉆井液設計密度為1.50 g/cm3,最優(yōu)抑制劑組合為3%KCL+0.4%KPAM+2%MMH。
[Abstract]:In order to reduce the complexity of second hole drilling in Tazhong block, this paper makes use of laboratory test and drilling and completion data synthetically, and analyzes the reasons for the mud-cladding of Triassic PDC bit and the instability of Permian wellbore. The corresponding countermeasures are put forward. The main contents and results are as follows: (1) the clay mineral composition, physical and chemical properties and microstructure of mudstone cores of Triassic and Permian strata were analyzed by laboratory tests. The test results show that the high clay content and strong dispersion of purple mudstone are the causes of repeated mudding of PDC bit, the high clay content and strong dispersion of brown mudstone are the objective conditions for the hydration collapse of brown mudstone. There are a large number of micropores in grey mudstone, intergranular pores and stratified fractures, which make the section with low clay content appear sidewall instability. (2) density and S-wave time difference are calculated by P-wave time difference. The parameters of mechanical properties of Permian strata, the pressure of overlying strata and pore pressure, the magnitude of horizontal in-situ stress are calculated, which provides the basic data for further study. The calculated results show that the Permian Poisson's ratio is 0.30-0.37, the elastic modulus is 7000-35000MPa, the tensile strength is 3-13MPa, the cohesion is 3-30MPa, and the internal friction angle is 20-35. The density of equivalent drilling fluid is 2.20-2.22 g / cm ~ 3, the density of formation pore pressure equivalent drilling fluid is 1.05-1.10 g / cm ~ 3, and the maximum horizontal stress is 2.35-2.55 g / cm ~ 3, respectively. The minimum horizontal stress is about 2.00-2.20 g/cm3. (3) from the viewpoint of mechanics, the stability of borehole wall is evaluated, the stress distribution around the well is analyzed, and the prediction model of formation collapse pressure and fracture pressure based on Mohr-Coulomb strength criterion is established. The formation collapse pressure and fracture pressure profile are calculated. The results show that the maximum collapse pressure of Permian is 1.45 g / cm ~ 3, and the contradiction between high collapse pressure and relatively low drilling fluid density is the mechanical reason of shaft wall instability. The fracture pressure is between 1.70 and 1.90 g/cm3. (4) the mud of Triassic PDC bit is selected and discharged optimally, the countermeasure of using drilling fluid cleaner is studied, and the stability of Permian wellbore is studied. Drilling fluid density design and optimal selection of drilling fluid inhibitors were studied. The results show that the use management of cleaning agent in block should be strengthened to reduce mud ladle, and drilling fluid discharge should reach 33L / s in 21.59cm well and 42 L / s in 24.13cm well. The design density of Permian drilling fluid is 1.50 g / cm ~ 3, and the optimal inhibitor combination is 3%KCL 0.4%KPAM _ 2.
【學位授予單位】：長江大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TE28
本文編號：2426944
[Abstract]:In order to reduce the complexity of second hole drilling in Tazhong block, this paper makes use of laboratory test and drilling and completion data synthetically, and analyzes the reasons for the mud-cladding of Triassic PDC bit and the instability of Permian wellbore. The corresponding countermeasures are put forward. The main contents and results are as follows: (1) the clay mineral composition, physical and chemical properties and microstructure of mudstone cores of Triassic and Permian strata were analyzed by laboratory tests. The test results show that the high clay content and strong dispersion of purple mudstone are the causes of repeated mudding of PDC bit, the high clay content and strong dispersion of brown mudstone are the objective conditions for the hydration collapse of brown mudstone. There are a large number of micropores in grey mudstone, intergranular pores and stratified fractures, which make the section with low clay content appear sidewall instability. (2) density and S-wave time difference are calculated by P-wave time difference. The parameters of mechanical properties of Permian strata, the pressure of overlying strata and pore pressure, the magnitude of horizontal in-situ stress are calculated, which provides the basic data for further study. The calculated results show that the Permian Poisson's ratio is 0.30-0.37, the elastic modulus is 7000-35000MPa, the tensile strength is 3-13MPa, the cohesion is 3-30MPa, and the internal friction angle is 20-35. The density of equivalent drilling fluid is 2.20-2.22 g / cm ~ 3, the density of formation pore pressure equivalent drilling fluid is 1.05-1.10 g / cm ~ 3, and the maximum horizontal stress is 2.35-2.55 g / cm ~ 3, respectively. The minimum horizontal stress is about 2.00-2.20 g/cm3. (3) from the viewpoint of mechanics, the stability of borehole wall is evaluated, the stress distribution around the well is analyzed, and the prediction model of formation collapse pressure and fracture pressure based on Mohr-Coulomb strength criterion is established. The formation collapse pressure and fracture pressure profile are calculated. The results show that the maximum collapse pressure of Permian is 1.45 g / cm ~ 3, and the contradiction between high collapse pressure and relatively low drilling fluid density is the mechanical reason of shaft wall instability. The fracture pressure is between 1.70 and 1.90 g/cm3. (4) the mud of Triassic PDC bit is selected and discharged optimally, the countermeasure of using drilling fluid cleaner is studied, and the stability of Permian wellbore is studied. Drilling fluid density design and optimal selection of drilling fluid inhibitors were studied. The results show that the use management of cleaning agent in block should be strengthened to reduce mud ladle, and drilling fluid discharge should reach 33L / s in 21.59cm well and 42 L / s in 24.13cm well. The design density of Permian drilling fluid is 1.50 g / cm ~ 3, and the optimal inhibitor combination is 3%KCL 0.4%KPAM _ 2.
【學位授予單位】：長江大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TE28
【引證文獻】
相關會議論文 前1條
1 樓一珊;莊錦江;黃榮樽;;巖石動靜彈性參數(shù)相關性研究及其在石油工程中的應用[A];巖石力學在工程中的應用——第二次全國巖石力學與工程學術會議論文集[C];1989年
，本文編號：2426944
本文鏈接：http://www.sikaile.net/kejilunwen/shiyounenyuanlunwen/2426944.html
教材專著
