大庆油田深层气井固井技术

Cementing Technologies for Deep Gas Wells in Daqing Oilfield

大庆油田深层气井平均井深4000～4500m，固井施工存在很多技术难点，例如地层裂缝发育、破裂压力低、地温梯度高、井径不规则、封固井段长等，施工过程中存在井口窜气、双级箍免通径成功率偏低等问题，为此，大庆油田采取了一系列相应的技术措施：优化井眼净化技术、研制或引进抗高温水泥浆体系、应用抗CO2腐蚀的TP—SUP13Cr套管和DCR防腐水泥浆、应用双级固井技术，从而有效地保证了固井施工的顺利进行和固井质量的提高。详细介绍了大庆油田特有的深层气井配套技术．指出了目前大庆油田深层气井固井存在的问题并提出了处理建议。

The average depth of deep gas wells in Daqing Oilfield is 4000 to 4500m. A lot of technical challenges exist during cementing operations, including the development of formation fractures, low fracture pressure, high formation temperature gradient, abnormal wellbore gauge, long sealing off section, etc. The problems, such as gas channeling on wellhead, easy to fail of double stage collar, etc. are easier to arise during cementing operations. Therefore, a series of technical measurements have been employed in Daqing Oilfield, including optimized technique for wellbore cleaning, development or introduce of high temperature cement slurry, application of anti-CO2 TP-SUP13Cr casing and DCR cement slurry and the use of double stage cementing technology. These techniques make cementing operations conducted successfully and the cementing quality was improved remarkably. This paper introduced in detail the cementing technologies for deep gas-wells in Daqing Oilfield. The existing problems in cementing technologies for deep gas-wells in Daqing Oilfield and the associated suggestions were proposed.