Real-Time Cementing Designs vs. Actual Jobs in Progress

Abstract

The cementing design process has been improved by using current technology to predict actual downhole conditions, allowing both the service provider and the well operator to manage fluid positions, critical circulating pressures and surface parameters while cementing casings in wells under stringent conditions. This paper explains how design data and real-time simulation of cementing jobs can be used to make detailed predictions of many well parameters and provide information allowing adjustments to be made during the cementing operation to alter the outcome or help improve the performance of the job. These tools can allow the operator and service provider tomore accurately predict cement tops,change casing programs,control flow-back rates and pressures,monitor equivalent circulating density (ECD) on specific zones, orenable personnel to create a better design for other wells in the field. The development of computer simulations to model surface and downhole conditions has been used for more than 26 years to improve and facilitate cementing operations under different and variable scenarios. By using this engineering computer program, many cementing failures can be prevented not only before the actual cementing operation is performed, but during the operation itself. Maintaining control and predicting problems is possible by taking into account all the monitored and calculated variables on a real-time mode and comparing the outputted prediction output with the pre-job design and the actual job in progress. Demonstrated by examples and case studies, the simulation process performs many steps needed to give precision to predictions in placement calculations. The computational process gathers information, and with multiple logical sequences, provides the most suitable solution for the scenario being studied. Multiple design program runs may be completed without jeopardizing the integrity of the well. While designing a plan, several parameters can be changed to predict the job performance or end results. Modifications or changes in various operational events for performance predictions may be used in making recommendations. Recommendations may be altered by changing such components as cementing materials, placement methods and even casing configurations to help ensure a better performance based on pre-job investigations. Introduction The zonal isolation behind casings achieved in the cementing processes is critical for the well's drilling and producing operations. Successfully performing a primary cement operation presents constant challenges and is best planned with up-to-date knowledge and engineering technology to achieve wellbore integrity and extended well life. The development of a computer simulation to model both surface and downhole conditions has been a valuable tool in use now for over 26 years. Its use has improved and facilitated cementing operations in complex and variable scenarios. The computer simulation program has constantly been scrutinized and modified through the years to improve its performance and the parameters it can handle based on observations and field engineering needs. By using this engineering computer simulation program, many cementing failures can be prevented not only before the cementing operation takes place, but during the actual operation itself. Maintaining control and predicting possible problems can be accomplished by analyzing all the monitored and calculated variables on a real-time mode and comparing these predictions with the pre-job design and the actual job itself. Ideally, in any computer-simulation process, many steps need to be evaluated to give precision to the predictions and calculations. The computational process gathers the information and, with multiple logical sequences, provides the most workable and suitable solution for the scenario being studied. Multiple design program evaluations and simulation runs may be completed at one's desk without jeopardizing the integrity of the well. While designing a plan, several parameters can be changed to predict the job performance or the calculated end results. Modifications or changes in various operational events are used in the development of recommendations. Recommendations may be altered by changing such components as cementing materials, placement methods or modes, and even casing configurations to help ensure a better performance.[1–6]