Both minimizing risks and providing adequate barriers are targets during cementing operations. This paper discusses key factors to consider during the design and execution of managed pressure cementing (MPC) operations in deep water. These factors are the result of important best practices identified for dependable results. The key learnings from different applications can provide more reliable MPC applications while minimizing associated risks.

Accurate data collection is necessary to understand cementing simulation results. The process discussed used pressure while drilling (PWD) to collect data, such as equivalent circulating density (ECD) and equivalent static density (ESD). This data, in combination with data generated at the surface from the annulus, and a fit-for-purpose temperature profile were then used in a state-of-the-art software to help replicate actual drilling wellbore conditions and enable model calibration for the cement operation. Using a calibrated model, MPC analysis performed during the planning stage was updated to help predict different MPC scenarios.

Cementing simulation results should provide the pumping schedule [e.g., volume in, volume out, planned surface backpressure (SBP), contingency SBP, and critical events along the schedule]. During the planning phase, the simulation results helped address misconceptions regarding MPC operations (e.g., rate out equal to rate in) and the SBP interpretation by accounting for surface equipment setup. The design accuracy was confirmed during the MPC application. Two cement operations were completed, with minor deviations that were addressed properly as a result of the analysis and risk assessment previously performed. Variable sensitivity (temperature, mud compressibility properties, fluids rheology, geometries downhole and at surface, MPD choke limitations) was important to maintaining SBP within the operational window to avoid influxes or losses. This paper discusses recommendations to provide guidelines for deepwater MPC design and execution.

MPC operations in deepwater environments have a few applications within the oil and gas industry. This paper provides important information that can help improve this method and provide optimal design modeling and analysis. Additionally presented are key factors for zonal isolation in deep water engineering and operative considerations for improvement of this unconventional method.

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