The temperature gradient in a giant gas field in the Middle East shows wide differences from one location to another. The drilling environment in slim single-lateral wells is challenging due to the substantial temperature anomalies resulting to multiple drilling tool failures where recorded downhole temperature exceeded 320 degF. This paper focuses on the first implementation of mud cooler with chiller packages in a gas drilling project and how it affected downhole temperature and well delivery performance. The process that led to the successful implementation of the technology can be summarized in four phases: the analysis of business drivers, preliminary temperature simulations and package design, and compatibility analysis, installation and operation. The identified business drivers included prevention of tool failures, optimization of drilling parameters, reduction of additional trips and the removal of the time-consuming staging procedure. To address these business needs importing HT tools did not seem to be the optimal solution as the temperature anomalies are not experienced in every well; the mud cooler and chiller offered the needed flexibility and cost-efficient solution. The mud cooler and chiller packages were implemented in a series of high-temperature gas wells and proved to be highly effective in rapidly decreasing the temperature of the mud at surface and substantially cooling down the downhole drilling tools. Maintaining a low downhole temperature throughout the section enabled the reservoir laterals to be drilled more efficiently, with less runs, and with no temperature-related tool failure. At surface, the mud temperature was lowered by more than 40 degF. Downhole temperature reduction measured by the drilling and measurement tools was up to 21 degF. Remarkable performance was achieved, such as the drilling of more than 3,000 ft of 5-7/8″ lateral in a single run while keeping the downhole temperature below 280 degF which was decisive in preserving the downhole tools. This project is a notable illustration of successful collaboration between different business units within the integrated service provider's organization to design and implement a fit-for-purpose solution to enhance tools’ reliability in high-temperature environments. The key elements which made the implementation successful in extending the runs and eliminating non-productive time for improved well delivery performance will be presented and described in length in the paper. Integration of the different technologies involved proved to be a key driver of innovation in the project and allowed for faster trials and deployment of new technologies and ways of working. Both the operator and the integrated services provider joined their efforts to achieve step changes in performance in high-temperature gas wells which can be successfully implemented elsewhere with all the main IOCs and NOCs.

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The Upper Cretaceous is a challenging drilling environment in Santos Basin, offshore Brazil. The lithology consists of highly intercalated layers of sandstone, siltstone and conglomerate from Santos and Jureia Formations. These formations are drilled vertically in 17 ½" intermediate hole and the length of the section varies from 1600 m up to 2000 m. Optimizing the drilling efficiency in this section is crucial to reducing drilling costs and non-productive time. During a recent exploratory campaign in Santos Basin, severe levels of shocks and vibrations were encountered while drilling this large and intercalated hole section, resulting in a low rate of penetration, premature bit wear, damaged tools, unplanned trips and drill string failures. Three to four bit runs were required to reach section TD. Post job information and drilling data were reviewed by an integrated operator-contractor team. A detailed engineering analysis of bit, BHA design and drilling mechanics was conducted to address the challenges of this section and propose a new approach to the drilling process. The key was the determination of the best combination of WOB and RPM to drill the different lithologies, together with more stable PDC bits, use of downhole motors and combined with specific operational procedures to mitigate shocks and vibrations. The proposed changes in bit selection and BHA configuration, drilling parameters and procedures, real-time monitoring and training have been successful. For the first time in the drilling campaign in Santos basin, it has proved possible to drill the 17 ½" hole in one bit run. The section was finished without any incident, under budget and under time. The improvement in drilling performance achieved with the implementation of this engineering study helped the operator to mitigate shocks and vibrations and save money, thus ensuring a more efficient drilling operation and preventing further drill string failures.

Real Time monitoring centers had focused on risk management, historic data review, trend analysis and wellbore stability awareness. In this abstract the transformation of a Drilling Real Time Monitoring Center is described, identifying new processes which, with no additional resources, developed a supplementary branch of real time monitoring: drilling performance optimization. The usage of daily received data and the potentiation of the RT Monitoring Software allowed to identify Removable Lost Time (RLT), optimizing drilling crews tripping time and connection times. A concerted effort to measure rigs suppliers through unified KPIs and daily performance reports which fomented competence and performance improvement. This step change delivered an OIC: Operations Integration Center which overhauled Mexico Land Drilling Performance creating a step change in daily operations with direct benefits to oilfield real time practices.