超声兰姆波成像测井仪在海上平台弃置的应用

Application of Ultrasonic Lamb Wave Imaging Logging Tool in Offshore Platform Abandonment

固井质量评价作为海上平台弃置时不可缺少的一环,直接影响着弃井成功与否。针对海上某油田C平台弃置时低密度水泥浆固井质量评价的难题,开展了超声兰姆波成像测井仪的研制,并进行了现场应用。研究表明:①超声兰姆波成像测井仪可对套管进行360°全井眼覆盖并成像显示,声阻抗测量精度为±15%,适用于常规及低密度水泥浆的固井质量评价,满足139.7~339.725 mm(5.5~13.375 in)套管内的固井质量评价;②C3井测量实例表明,超声兰姆波测井仪评价结果与现场套管切割后回收断面符合度高,为后续套管切割作业提供了可靠依据。超声兰姆波成像测井仪具有一定的应用推广价值。

As an indispensable part of offshore platform abandonment,cementing quality evaluation directly affects the success of offshore platform abandonment.In view of the difficult problem of evaluating the cementing quality of low density cement slurry when the C platform of an offshore oil field is abandoned,an ultrasonic Lamb wave imaging logging tool was developed and it was applied in field.The result shows that the ultrasonic Lamb wave imaging logging tool can finish 360°coverage and imaging display of casing.The accuracy of acoustic impedance measurement is±15%,and it is suitable for the cementing quality evaluation of conventional and low-density cement slurry in the casing wells of 139.7~339.7 mm(5.5~13.4 in).The measurement result of C3 well shows that the evaluation result of the ultrasonic Lamb wave logging tool is in good agreement with the recovered section after casing cutting,which provides a reliable basis for the subsequent casing cutting operation.The ultrasonic Lamb wave imaging logging tool has certain application popularization value.