连续油管打捞连续油管工艺在低压低产气井中的应用

为了解决在低压低产气井生产管柱中打捞连续油管的难题,提出了连续油管打捞连续油管的工艺思路,并结合低压低产气井的实际特点,配套研发了一系列专用打捞工具,并将该工艺应用在塔里木盆地塔北隆起轮台凸起西端羊塔克凝析气田的T1井。研究结果表明:①射流解堵疏通作业通道、打铅印验证鱼顶形状、提拉测试确定上提载荷正常区间是打捞作业顺利进行的必要前提;②自旋引入工具可以实现连续油管的旋转打捞功能,抓获—剪切工具可以实现落鱼抓获以及极端情况下剪断落鱼的双重目的,防止作业管柱断脱进而造成更为严重的井下事故,而基于泵压的变化,抓获检测工具可以及时检测到鱼顶是否引入,有效避免引入过程中盲目施加载荷挤断落鱼的情况发生;③低压低产气井T1井长期关井且生产通道完全阻塞,同时作业通道存在着较多的变径位置,应用该打捞工艺进行了13次打捞,均将鱼顶成功引入且捞获,成功率达100%。结论认为,该工艺适用于空间受限情况下打捞连续油管的作业,可以为低压低产气井生产管柱内打捞连续油管难题的解决提供有效的方案。

Application of fishing coiled tubing by using coiled tubing in gas wells with low pressures and low production rates

In order to solve the problem of coiled tubing fishing in the production string of gas wells with low pressures and low production rates, this paper puts forward a technical idea of fishing coiled tubing by using coiled tubing. Combined with the actual characteristics of gas wells with low pressure and low production, a series of special fishing tools were developed. And the technology was applied to Well T1 of Yangtake Condensate Gas Field in the western end of Luntai salient, Tabei uplift, the Tarim Basin. And the following research results were obtained. First, the necessary prerequisite for the smooth fishing operation is to unblock the operating channel by jet flow, verify the shape of the fish top by lead-in printing and determine the normal lifting load range by pull-up tests. Second, by virtue of the spin-in tool, the rotation fishing function of coiled tubing can be realized. By virtue of the catching-cutting tool, the dual purpose of catching fish and cutting fish in extreme cases can be achieved, so as to prevent the operation string from being broken and falling, which may cause a severe downhole accident. Based on the change of pump pressure, the capture detection tool can detect whether the fish top is introduced or not in time, effectively avoiding the situation that the fish is squeezed and broken due to blind loading in the introduction process. Third, Well T1, a gas well with low pressure and low production rate, has been shut down for a long time and its production channel is completely blocked. In addition, there are many variable diameter positions in the operation channel. After this fishing technology is applied in Well T1 for fishing 13 times, the fish top is successfully introduced and fished with a success rate of 100%. In conclusion, this technology is applicable to coiled tubing fishing under the condition of limited space, and it provides an effective solution for the difficult fishing of coiled tubing in the production string of gas wells with low pressures and low production rates.