百色油田调整井固井技术研究与应用

百色油田由于注采不平衡，纵向上形成多压力层系，给调整井固井带来很大的困难，通过分析百色油田调整井固井封固后环空油气水窜槽的原因，认为提高调整井固井质量必须改善水泥浆在井下的胶结环境和提高水泥浆的防窜性能。百色油田调整井采取的主要固井技术措施施为，使用双纠套管扶正器，使套管居中不偏心，采用快体冲洗液，并加以大量的低密度水泥浆前置液，尽量消除泥饼对水泥胶结的影响，提高界面胶结强度和质量，采用具有直角稠化，短侯凝，超短过滤，低失水，高早强，微膨胀性能的防窜双凝水泥浆体系和环空憋压候凝措施，达到压稳，防窜的目的，在水泥浆中引入膨胀剂和套管内敞压候凝技术，消除因内部压力和水泥浆固有的膨胀－收缩特性而造成的微缝－微孔隙，实现环空密封。经6口井现场应用表明，该固井工艺技术措施解决了百色油田薄油层，薄隔层的封固难题，提高了百色油田的固井质量。

Study and application of adjustment well cementing in Baise Oilfield

The injection imbalance in Baise Oilfield causes multi-pressure layer vertically, which results extreme difficulties in cementing the adjustment wells. By analyzing the causes of oil, gas and water channeling in the annular after cementing, it is suggested that to improve the cementing quality of the adjustment wells, the downhole bonding environment, as well as the anti-channeling property of the cement slurry must be improved. The main technical measures taken in the cementing of adjustment wells in Baise Oilfield include; using of double-bow casing centralizers to centralize the casing; using of new type of flushing fluid treated with mud cake breaker, and aided by large volume of low weight slurry as pad fluid, to minimize the influence of mud cake to the bonding of cement slurry, thus improve the bonding strength and quality. Using of the anti-channeling double setting cement slurry systems, which has such advantages as short thickening, WOC and transmitting time, less fluid loss, high early strength and minimal inflation, aided by the bumping WOC measures in the annular to stabilize and keep thechanneling from taking place. Adding the swelling agent in the slurry and adopting the opening WOC technology in the casing, to eliminate the micro-fractures or pores caused by the inner pressure and the inflation-contraction feature of the cement slurry, to seal off the annular. Field using in 6 wells shows that these technologies solve the cementing difficulties of thin layers and thin isolation zones, and greatly improves the cementing quality in Baise Oilfield.