保温隔热油管井筒温度分布计算耦合模型

Coupling model for calculating wellbore temperature distribution of thermal insulation tubing

“保温隔热油管+设置了导电铜质母带的保温隔热油管”在老油田二次开发“重构注采关系、重构地面工艺流程”中取得了很好的应用效果。准确计算下入深度的组合方式,既可以满足油田开发的需要,又可以节约采购成本。为此,建立了井筒内井轴温度场控制方程,构建了井筒温度分布模型,阐明了油井井筒内半径与套管外半径之间的综合传热系数,保证了温度分布模型求解的稳定性和收敛性。对50余口油井进行的井筒温度分析和保温隔热油管组合下深设计实践表明,井口温度平均提高18.4℃,井口回压平均降低0.47 MPa,既满足了井筒原油举升、又满足了地面单管集油进站的条件。建立的模型也可为自喷井、注氮气井等保温隔热油管工艺参数设计提供理论依据。

The "thermal insulation tubing + thermal insulation tubing with conductive copper busbar" has achieved good application results in "Reconstructing injection-production relationship and surface process flow" in the secondary development of old oilfields.The combination method of accurately calculating the running depth can not only meet the needs of oilfield development, but also save the procurement cost.Therefore, the control equation of shaft temperature field in the wellbore is established, the wellbore temperature distribution model is constructed, and the comprehensive heat transfer coefficient between the inner radius of the oil well wellbore and the outer radius of the casing is clarified, which ensures the stability and convergence of the solution of the temperature distribution model.More than 50 oil wells have conducted wellbore temperature analysis and deep design practice of thermal insulation tubing combination.The average wellhead temperature is increased by 18.4 ℃ and the average wellhead back pressure is reduced by 0.47 MPa, which not only meets the needs of wellbore crude oil lifting, but also meets the needs of surface single pipe oil gathering and entering the station.The established model can also provide a theoretical basis for the process parameter design of thermal insulation tubing such as flowing wells, nitrogen injection wells.