Φ177.8 mm×Φ193.7 mm composite liner hanging and cementing technology of LG37 well

Downhole conditions of LG37 well are very complicated, because leakage layer, massive gypsum-salt layer, and high-pressure saline layer may be encountered during the drilling process. So it is determined to complete drilling when drilled to the depth of 5900 m, ?177.8 mm×?193.7 mm composite liner is applied to cementing.The first grade triple-setting sand, anti-channeling, leak-proof, salt-resisting heavyweight cement slurry system is applied to the cementing. The cement slurry system has favorable performance in controlling water loss, leakage loss and anti-channeling. Cementing operations are completed successfully, by applying the technologies of primary cementing to top cement, making anti-sulfur ?193.7 mm casing with extraordinary thickness and high resistance to extrusion into the gypsum-salt layer, and running external casing packer to the saline layer. The successful experience in composite liner hanging and cementing could provide reference for cementing operations in similarly complex wells.