Ultra Deepwater Cementing Development and Field Applications in Western South China Sea

Abstract

Cementing operation of ultra deepwater well in western South China Sea is notoriously difficult due to low temperature, soft seabed and shallow water flow. Novel ultra deepwater early-enhanced strength additive PC-DA92S and PC-DA93L developed with monomer complex technology and filtrate reducer PC-DG72S developed with suspension polymerization technology have been introduced in order to cope with aforementioned problems. According to the actual conditions in western South China Sea, two sets of suitable cement slurry system have been developed. Properties of cement slurry systems have been analyzed and evaluated. After being applied in Well LSX-1-1 in western South China Sea, it is concluded that these two sets of cement slurry system are characterized by early-enhanced strength, low filtrate, outstanding anti-channeling capability, user-friendly in adjusting thickening time, and stable cement slurry rheological properties at low temperature. Therefore, the outcomes reveal these two sets of low density with early-enhanced strength Class-G Portland cement slurry system can successfully meet the requirements of cementing operation for ultra deepwater region in western South China Sea.

An Experimental Study on the Reinforcement of Weakly-Consolidated Shallow Formation in Deep Water Using an Epoxy Resin-Based Fluid

“…Under this condition, the cement sheath is similar to a boat floating in the weakly consolidated shallow formation, providing limited strength to support the long-term stable service of the wellbore. Many methods have been applied to address these cementing problems, such as improving the cement slurries [10][11][12][13][14][15], reinforcing the mud cake [16], enhancing the bonding strength of the cement-formation interface [17], and using self-healing cement technology [18,19]. However, the cement-formation interface and mud cake are too thin to prevent the failure of the brittle cement sheath.…”

Hydration kinetics of oil well cement in the temperature range between 5 and 30°C

“…Offshore hydrocarbon resources account for 60% of global hydrocarbon resources, and 30% of these resources are distributed in deep water areas (Liu et al, 2017). Natural gas hydrate is often considered a hazard during deep-water well drilling and completion.…”