油气井井筒完整性系统风险评估方法

常规油气井井筒完整性风险性评价方法只是针对单一工况的，目前还没有油气井整个寿命周期内井筒完整性系统风险评价方法。为此，将油气井井筒关键结构（点）（如完井油套管柱、水泥环等）完整性风险评估和考虑多种工况的井筒综合完整性评估相结合，提出了油气井整个寿命周期（包括钻井、完井、生产、弃井等4种工况）的井筒完整性系统风险定量评估方法，建立了油气井井筒完整性系统风险定量评估模型和评价指标。利用该风险评估方法对普光气田气井整个寿命周期内的井筒完整性风险进行了评估，结果发现该气田气井井筒完整性风险较高，与现场情况相符。研究表明，利用提出的油气井井筒完整性系统评估方法可以评估油气井整个寿命周期内的井筒完整性风险，为降低油气井井筒完整性风险提供依据。 

Techniques for Systematic Risk Assessment of Borehole Integrity of Oil and Gas Wells

Risk assessments of wellbore integrity of conventional oil and gas wells are predominantly performed in one certain working condition at one specific time without systematic risk assessment method for wellbore integrity of oil and gas wells throughout the well life cycle.To correct the deficiency,systematic and quantitative assessment techniques were proposed for drilling,completion,production,plugging and abandoning. Thus,four kinds of conditions in the whole life cycle of oil and gas wells and they constitute a comprehensive evaluation of the wellbore. In this way,systematic risk quantitative assessment models and evaluation indicatorsfor oil and gas wells wellbore integrity were established.Risks in wellbore integrity in the whole life cycle of the Puguang Gas Field were estimated by using aproposed risk assessment method. Assessment results showed that the integrity of the wellbores in the field were operating at a higher risk level and it was verified with actual conditions on site. Research results showed that wellbore integrity evaluation method can evaluate the risk of wellbore integrity in the whole life cycle of oil and gas wells,and can provide valuable references for minimizing the risk of wellbore integrity of oil and gas wells.