On January 21st, the Wunan 3-2-13X well of the Tarim Oilfield was officially put into operation. This well successfully completed the lowering of the retrievable electric pump and achieved a qualified trial pumping within the middle of this month. It realized the application of the retrievable electric pump lifting technology at a depth of 2500 meters, providing a new technical approach for the Tarim Oilfield to cope with complex working conditions, significantly reducing maintenance and inspection costs, and improving efficiency.
Electric pump lifting is an important artificial lifting method in oilfield crude oil production. As the oil and gas development in the Tarim Oilfield continues, electric pump wells generally face complex production environments such as asphaltic deposits in heavy oil, sand blockage of the pump, and high gas-liquid ratio after gas injection, which leads to an increase in the failure rate of the units and a shortening of the inspection and maintenance cycle. This technology adopts a dual-layer pipe string of "outer cylinder + inner cylinder", and when the electric pump unit fails, there is no need to use the complex large-scale well repair machine for a complete set of lifting and lowering operations. Only a conventional cable car and the dedicated fishing tool need to be used to safely and reliably retrieve the inner cylinder unit from the wellhead, replace the new unit, and then re-enter it into operation. The outer cylinder pipe string and the cable remain stationary throughout the process, significantly reducing the inspection and maintenance time and lowering the operation costs.
The successful trial is not only a major technological breakthrough in the lifting technology field of the Tarim Oilfield, but also provides a new solution for the quality improvement and efficiency enhancement of deep wells and complex working condition wells in old oilfields.