针对深水油气井浅层固井存在的逆向温度场,对水泥浆在低温下的稠化时间、抗压强度和流变性能进行了分析,结果显示:在低温下水泥浆的稠化时间明显延长,抗压强度发展缓慢,流变性能变差.因此,针对深水固井试验中温度模拟方法与陆地固井的不同,介绍了深水固井循环温度和静止温度的确定方法,设计了可以用来测试深水固井水泥浆性能的稠化试验装置及静胶凝试验装置.同时设计了不同密度的深水固井水泥浆配方,并对其性能进行了测试,结果表明,所设计的不同密度深水固井水泥浆,在低温条件下早期强度发展快(4 Mpa/16h),流变性好,防气窜能力强,沉降稳定性能好,能满足深水表层套管固井的需要.%For the problem of reverse temperature gradient in shallow formation cementing for deepwater drilling,the thickening time, compressive strength,and rheology of cement slurry at low temperature were analyzed. The results indicate that an obvious long thickening time,a slow development of compressive strength and a poor rheology were observed at low temperature. Since the temperature simulation method in deep water cementing experiment is different with that of onshore,this paper presents the method for predicting bottomhole circulating temperature (BHCT) and bottomhole static temperature (BHST).Test equipment to measure the performance of deepwater slurry thickening and static gel test equipment were designed. The deep-water slurry formula with different densities was developed, and the performance was tested. The test results indicate that the cement slurry has a rapid compressive strength development at 4 ℃ (4 MPa/16 h) ,a good rheology,anti-gas migration ability and no sedimentation. The cement slurry can meet the requirement for cementing the upper casing string in deepwater wells.
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