顺北16X井二次侧钻超高温钻井液技术OACSTPCD

The well Shunbei-16X is a well drilled in the#16 fault zone in Shunbei area by Sinopec Northwest Petroleum Bureau.This is a four-interval deviated exploration well drilled to the Yingshan formation of the Ordovician system.The temperature at 6,680 m was predicted to be 168.9℃.After drilling to the designed depth of 6,777 m,decision was made to deepen the well with a high performance drilling fluid ENVIROTHERM NT.The drill pipe got stuck and the well was plugged,then sidetracked with an oil-based drilling fluid.Well test showed no industrial oil production.The well was then re-plugged and sidetracked again with a high temperature drilling fluid.The second sidetracking of the well was done to 7,533 m MD/7,417 m TVD,the bottom hole temperature measured was 209℃,and the maximum mud density was 1.75 g/cm3,indicating that the formation at the total depth of the well is an extremely high temperature ultra-high pressure formation.The high performance drilling fluid used to drill the sidetracked section of the well had excellent rheology and settling stability at extremely high formation temperatures as well as excellent resistance to CO2 and formation water contamination.The second sidetracking was successful,and no downhole troubles were ever encountered.