Investigation of Wellbore Temperature Dynamics during Cement Setting in Deepwater Shallow Formations

Offshore deepwater cementing generally faces more challenges than onshore cementing. Shallow formations in deepwater wells often exhibit low structural strength, high porosity, and are prone to shallow gas influx and hydrate formation. These factors require careful control of hydration heat. In this article, we examine the key factors influencing temperature fluctuations in the wellbore and develop a temperature model that accounts for the thermal effects related to cement slurry circulation and hydration. This model is then applied to a deepwater shallow formation cementing case study. The results show that: (1) When cement slurry is displaced into deep-water shallow formations, it loses heat due to seawater-induced cooling before entering the wellbore. This lowers the temperature of both the slurry and the wellbore before cement hydration begins. (2) The main production of heat due to cement hydration occurs during the pre-induction and acceleration stages. These are also the critical phases that affect formation temperature in deep-water shallow formation cementing. According to Kutasov’s semi-analytical equation, the peak heat release happens 8–12 h after cementing, resulting in a temperature rise of up to 40°C and 30°C for 26″ and 12-1/4″ boreholes, respectively.