Abstract: Well Wusheng 1 of Dagang Oilfield is designed to the total depth (TD) of 6000m. The second spudding of ?444.5mm well bore is to the depth of 2980m. ?339.7mm casing is set to the depth of 2983.88mm. The female casing coupling is deformed to make up improperly, due to the big size of casing, deep setting depth and heavy hanging load. Even if two-stage cementing is used, the pressure of common slurry will be greater than formation breakdown pressure, thanks to the long barefoot interval and the low formation pressure factor. After relative measures are used, the run casing operation and cementing job are per formed successfully. The quality of cementing is high and meets requirement of design.