As a controllable power generation method requiring no energy storage, Ocean Thermal Energy Conversion (OTEC) technology demonstrates characteristics of abundant reserves, low pollution, and round-the-clock stable operation. The free-standing cold-water pipe (CWP) in the system withstands various complex loads during operation, posing potential failure risks. To reveal the deformation and stress mechanisms of OTEC CWPs, this study first analyzes wave particle velocity and acceleration to determine wave loads at different water depths. Based on the Euler-Bernoulli beam model, a quasi-static load calculation model for OTEC CWPs was established. The governing equations were discretized using the finite difference method, and matrix equations were solved to analyze bending deformation, bending moments, and surface stresses at discrete points along the pipe. Results indicate that water depths within 50 m represent a critical zone where wave particle velocity, acceleration, and wave loads exhibit significant variations in harmonic patterns, while beyond 50 m depth wave loads decrease linearly. Ocean currents and surface wind-driven currents substantially influence the CWP’s lateral displacement. Considering the effect of clump weights, the maximum lateral displacement occurs at 600–800 m below sea level. Utilizing large-wall-thickness high-strength pipes at the top section significantly enhances the structural safety of the CWP system.

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.