本文選題：固井 + 水泥漿��； 參考：《西南石油大學(xué)》2016年碩士論文

【摘要】：固井后環(huán)空帶壓問題一直是固井界的一個(gè)技術(shù)難題,大部分天然氣井在固井后都會(huì)面臨這一問題。導(dǎo)致環(huán)空帶壓的一個(gè)主要原因就是環(huán)空氣竄,而引起環(huán)空氣竄的原因很多,其中水泥漿防竄性能對環(huán)空氣竄會(huì)產(chǎn)生重要的影響,水泥漿在凝結(jié)過程中的體積收縮是水泥漿防氣竄性能的重要指標(biāo)之一。因此探究水泥漿體積收縮對氣竄的影響機(jī)理,對于水泥漿防竄性能的設(shè)計(jì)有著重要的指導(dǎo)意義。本文在現(xiàn)有研究的基礎(chǔ)上從體積收縮過程及影響因素出發(fā),開展了不同階段體積收縮對氣竄影響的研究。從水化反應(yīng)及水化過程出發(fā)結(jié)合體積收縮曲線、水化熱曲線和TGA曲線對體積收縮的成因及收縮的過程進(jìn)行了分析,發(fā)現(xiàn)在水泥水化過程中自由水向束縛水和化學(xué)結(jié)合水轉(zhuǎn)化的越多,體積收縮率就越大。通過OWC-1102型高溫高壓水泥漿體積收縮儀和比長儀測試分析了不同水泥漿體系的體積收縮率,并對體積收縮的影響因素及影響機(jī)理進(jìn)行了研究,發(fā)現(xiàn)90℃下水灰比從0.3增加到0.6,初凝時(shí)刻對應(yīng)的體積收縮率增加了0.24%,終凝時(shí)刻對應(yīng)的體積收縮率增加了1.2%；90℃下加入35%的硅粉較未加硅粉的基礎(chǔ)配方初凝時(shí)刻對應(yīng)的體積收縮率降低了0.38%,終凝時(shí)刻對應(yīng)的體積收縮率降低了0.69%；加入15%的礦渣和未加礦渣的基礎(chǔ)配方相比初凝時(shí)刻對應(yīng)的體積收縮率降低了0.17%,終凝時(shí)刻對應(yīng)的體積收縮率降低了0.46%。選用了合理的實(shí)驗(yàn)手段和方法測試了不同階段的體積收縮、水泥漿凝結(jié)過程中孔隙壓力的變化、水泥漿凝結(jié)硬化后界面膠結(jié)強(qiáng)度的變化,結(jié)合氣竄成因重點(diǎn)分析了初凝前體積收縮和凝結(jié)硬化后體積收縮這兩個(gè)階段的收縮對氣竄的影響,實(shí)驗(yàn)數(shù)據(jù)分析表明：初凝前的體積收縮率從0.81%降到0.39%時(shí),初凝時(shí)刻的孔隙壓力降低值從0.9MPa降低到0.3MPa,一、二界面的膠結(jié)強(qiáng)度隨著體積收縮率的增加而逐漸降低；同時(shí)有鉆井液濾餅存在時(shí),體積收縮對界面膠結(jié)強(qiáng)度的影響更大；通過計(jì)算膠結(jié)強(qiáng)度增長速率分析對比了有無鉆井液濾餅存在條件下外觀體積收縮對膠結(jié)強(qiáng)度的影響規(guī)律；從水泥漿配方優(yōu)化方面提出了改善水泥漿體積收縮的措施,室內(nèi)實(shí)驗(yàn)結(jié)果表明優(yōu)化后的水泥漿體系的常規(guī)工程性能良好,體積收縮性能得到了一定的緩解。由于實(shí)驗(yàn)條件的限制本文關(guān)于水泥漿初凝到終凝之間的體積收縮率對氣竄的影響未做深入研究,建議后續(xù)對此部分內(nèi)容進(jìn)行深入研究。
[Abstract]:The post-cementing annular zone pressure problem is always a technical problem in cementing field, and most natural gas wells will face this problem after cementing. One of the main causes of annular zone pressure is annulus air channeling, and there are many reasons for ring air channeling, among which the anti-channeling performance of cement slurry has an important effect on annular air channeling. Volume shrinkage of cement slurry during solidification is one of the important indexes to prevent gas channeling of cement slurry. Therefore, it is of great significance to study the influence mechanism of cement slurry volume shrinkage on gas channeling for the design of cement slurry anti-channeling performance. In this paper, based on the existing studies, the effects of volume shrinkage on gas channeling in different stages are studied from the point of view of volume shrinkage process and influencing factors. Based on hydration reaction and hydration process combined with volume shrinkage curve, hydration heat curve and TGA curve, the causes and process of volume shrinkage were analyzed. It is found that the more free water transforms into bound water and chemically bound water in the hydration of cement, the larger the volume shrinkage rate is. The volume shrinkage rate of different cement slurry systems was analyzed by OWC-1102 high temperature and high pressure cement slurry volume shrinkage meter and specific length meter, and the influencing factors and influencing mechanism of volume shrinkage were studied. It is found that the volume shrinkage at the initial setting time increases by 0.24, and the volume shrinkage at the final setting time increases by 35% at 90 鈩，

本文編號：1997935