YD油田沥青层安全钻井技术

Discussion on Safe Drilling Technologies for the Asphalt Layer in the YD Oilfield

在YD油田钻穿沥青层的过程中,易出现沥青侵入导致的溢流、井涌等井下故障,极太影响了钻井安全,为此,开展了YD油田沥青层安全钻井技术研究。根据已钻井的沥青侵入特点、沥青所造成的井下故障及采取的主要技术措施,将钻遇沥青层的井分为4类。对YD油田钻遇沥青层时所采用技术及采取的技术措施进行了总结,并结合钻遇沥青层井的分类,提出应根据沥青侵入的特征及程度,采用相应的安全钻井技术并采取相应的技术措施。YD油田的钻井实践表明,针对不同类型的沥青侵入情况采用相应的钻井技术和技术措施,可以解决YD油田沥青层安全钻井的技术难点。

During drilling through asphalt layer in the Yada Oilfield,asphalt invasion posed a lot of down-hole issues such as mud contamination,well kick and mud loss coexistence,bringing tremendous challenges in operation.In order to solve those problems,studies were conducted on safe drilling technologies for the asphalt layer in the YD Oilfield.Depending on asphalt invasion characteristics,induced downhole issues and major techniques and measures taken,the wells were divided into 4classes.The techniques and measures applied in drilling through asphalt layer in the YD Oilfield were summarized.For each of the4 classes of wells,it is proposed to employ specific drilling techniques and measures depending on the characteristics and extent of asphalt invasion.The drilling practices in the YD Oilfield demonstrated that specified drilling techniques and measures should be implemented depending on types of asphalt invasion in order to effectively ensure the safe drilling through asphalt layer in the YD Oilfield.