Aiming to revive the target well’s productivity, Jereh’s technology experts drew on their experience of unblocking ultra-deep high-pressure gas wells in the Tarim Oilfield. They created "a solution that used coiled tubing for sand washing and milling without removing the production string". However, it was rather complicated to operate in the target gas well. There are high risks of losing control and sticking of drill pipes, while the down-hole tools might not be able to work in an environment of ultra-depth, high temperature and corrosive gas. To overcome those negative factors, Jereh team chose a premium tool string in combination with reliable ground control systems, including the choke control valve, and de-sanding and filtering system, while using sand washing fluid with thermal-stability and low friction.