The Need for a Comprehensive Cement Database - A Novel Approach to Best Practices by Cataloging Cement Properties

In conventional well design, the cement sheath acts as one of the primary barriers of protection in the well integrity matrix. Once the wellbore cement is set, the well is exposed to various conditions and environments over time which can impact the integrity of the cement, the results of which are poorly studied and documented. Given that there are also multiple cement recipes and formulations – the task of studying downhole cement performance and categorizing said results becomes more complicated, requiring the need for an integrated database of information. The objective of this paper is to document desirable cement properties, develop an optimal method for presenting this data, and construct a database which integrates this information and allows streamlined data entry and retrieval. Multiple variables must be considered when aggregating cement recipes and its corresponding properties over time. To test the behavior of these cement recipes over time, samples are created and aged in various controlled environments, and the properties tested periodically. The database was developed with a suitable interface to provide intuitive data entry and practical analysis capability, with proper inputs for the types of cement used, additives added, properties of the cement mixtures over time and any corresponding analysis performed on the samples in order to maximize best practice. Differences in geology, drilling techniques and standards often require the use of different cement recipes with varied additives to cater to each job. These include accelerators, retarders, extenders, weighing agents, fluid and loss control additives, as well as special additives such as latex, fiber additives and foam cements. The database interface is designed to accommodate these variations in the cement recipes and track the properties of samples over time and give a comprehensive understanding of the behavior of the samples as they age. With information from the industry, literature, and laboratory experiments, properties such as the Unconfined Compressive Strength (UCS), thickening times, gel strength development, densities, to name few will be integrated in the data base. Data analytics strategies will also be applied on the information aggregated, and the properties of the samples over time will be correlated to field data as well as literature to ensure proper representation and accuracy of the data. The database and the knowledge collected will be utilized as a source of information to enhance common cementing practices, as well as develop and refine industry best practices, which will be applicable to any cement job in the world. Currently, the database presented in this paper contains over 1000 unique cement samples, prepared and documented by multiple individuals with an aim to create a unique cement repository and database that focuses on long term cement properties.