Countermeasures for collapse in super-deep wells in Tahe Oilfield

Due to the special geological structure in the Tahe Oilfield, most of the Ordovician wells are in open-hole completion, and parts of the mudstone and limestone production layers are exposed. Well collapses are common in the recent years, in view of which, many studies and field practices have been carried out. This paper mainly aimed at the countermeasures for collapse, and classified them into mild, severe, repeat ones and compound comprehensive accident. Corresponding countermeasures were given, especially assembly tools, drill grinding, grinding parameters in operation.