热力采油是开采稠油的最广泛、效益较高的方法,但在热采时,油层套管因热效应破坏比较严重。针对稠油热采井套管热破坏的问题,提出了防止其热破坏的预膨胀固井技术,即在注水泥结束但没有凝固时,将油层套管预热和向油层套管施加内压强,使套管膨胀;水泥在套管膨胀状态下凝固。根据现场生产实际和预膨胀固井理论要求,设计了热采井预膨胀固井模拟实验装置。并模拟了常规固井、半预热固井和预压固井工艺以及注蒸汽和生产过程。实验结果表明,采用预膨胀固井技术能有效防止热采井套管注蒸汽热破坏。为下一步的现场试验与应用奠定了基础。
The thermal recovery is a common and effective method for producing heavy oil.The casing failure is a very serious problem in thermal recovery wells.In view of this problem,it is proposed the technique of casing cementing with internal pre-expansion for thermal recovery well.It refers to exert inner pressure on payzone production casing or heat payzone production casing to a certain temperature and make payzone production casing expand in cement solidifying period.We developed simulating experiment table according to field practice and pre-expansion cementing theory.It can simulate cementing technology including conventional,half warm-up and internal pressurization cementing technology,as well as steam injection and production process.The technique will be an important foundation for the following field tests and its application.