Knowledge and practice of leakage casing and tube plugging in Tahe ultra-deep and super-heavy oil oilfield

During the development of the Tahe Oilfield, well casing leaks more and more seriously year by year. Restricted by well depth, heavy oil, high temperature, high salinity, high hydrogen sulfide corrosion, well bundle structure and light oil injection, the conventional methods of leakage casing fail to meet the demand of the Tahe Oilfield which is featured by ultra-deep and super-heavy oil. The practices of leakage casing and tube plugging in 14 wells are analyzed, summarizing the corresponding conditions for 4 methods of leakage casing and tube plugging in ultra-deep and super-heavy oil wells. The advantage and disadvantage of 2 methods are discussed. Applications of leakage casing and tube plugging are made for 11 times in 10 wells, adding up oil by 5.86×10⁴ t.