Steam channeling is one of the main factors influencing production. Taking the high-dip angle area in the Qi-40 block of the well group 65 in Liaohe oilfield as an example,the steam injected into the reservoirs tends to channel upwards by density difference and causes production to decline, especially in reservoirs with high-dip angle. The numerical simulation analysis of oil saturation for the well group 17-028 shows that the remaining oil distributes mainly in down-dip bottom of the reservoirs. Based on the study we put forward three adjusting schemes: drilling new wells, reorganizing the well pattern and performing gravity drainage. Comparison of the operation index of these three schemes shows that gravity drainage through simply adjusting steam injection parameters is the most effective and the simplest scheme of all. By performing the technology, we could produce a uniform downward pressure gradient and push the steam to flow down. Through optimization of the technology, we could determine the reasonable parameters for steam injector. The prediction shows that the recovery-reserve ratio of the high-dip angle area in the Lotus Ⅱ reservoir can reach 7. 4% when the dryness degree of the upper steam injector array is 30%,and the gas injection volume of the middle and lower steam injector arrays declines by 20% and 50% respectively. Field testing indicates that the technology is feasible in oilfield development since it can effectively slow down steam channeling and increase gas-oil ratio.%蒸汽驱汽窜现象是导致产量急剧下降的主要原因.以辽河油田齐40块65井组高倾角区为例,由于密度差的原因,注入油层中的蒸汽具有上浮的趋势,具有高倾角的油层将加剧这种汽窜现象,导致产量下降.17-028井组含油饱和度数值模拟图分析表明,油层的剩余油主要分布在下倾方向底部.从而可得出3种调控方案:新井挖潜、重组井网和重力驱油.通过方案作业指标对比,仅通过调整注汽参数实现的重力驱油方案操作简单,无任何作业工作量.综合评价认为,重力驱油方案为最佳调控方案.该方案可在地层中产生一致的、向下的压力梯度,实现蒸汽向下移动.确定技术后对其进行优化,确定合理的注汽井参数.预测结果表明,当上排井注汽干度为30％时,中排井注气量下降20％；下排井注汽量下降50％时,莲Ⅱ油层高倾角地区采出程度可达7.4％.经现场试验,此项技术可以使汽窜现象减缓,油汽比提高,在油田开发中为可行方案.
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