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Various sized bridging materials (SBMs) such as ultra-fine, fine, medium and coarse grade SBMs are frequently used in drill-in fluid formulations to improve drilling fluid properties, enhance mudcake quality and reduce near wellbore formation damage. The mechanical properties, especially the material toughness of the SBMs play an important role in fulfilling these functional tasks. Weak and easily disintegrating SBMs are unable to maintain the functional capability of drill-in fluid due to a major change in the planned particle size distribution in the fluid. Hence, drill-in fluid containing rapidly degrading SBMs shows poor performance while drilling. This highlights the need for selection of very tough and high strength SBMs to design superior drill-in fluid for non-damaging drilling operation in the pay zone. However, the industry lacks a suitable method for screening, testing, evaluation, quality control and quality assurance of SBM products to select the best and reject the worst and the inferior. Hence, there is a need of development of a quick and reliable SBMs characterization method to use as a guiding tool for designing superior and high performance drill-in fluid for non-damaging drilling operation. Historically, color, provenience, origin, degree of diagenesis and metamorphism of the SBM samples or acid solubility were evaluated to use as a guiding tool to select highly durable and mechanically strong SBM products. These subjective and inappropriate methods of assessment frequently lead to disastrous SBMs performance. Due to the limitation and ambiguity of the petrographic and acid solubility methods, attempt was made to identify high quality SBMs by using Brinnel Hardness Tester. The outcome of the research was inconclusive and provided no guiding tool for SBMs performance evaluation. Failure of the above approaches lead to the development of the Aramco method for characterization, quality control and quality assurance of SBMs. Though the method is good for coarse and medium grades SBMs, it has some limitations for fines and ultra-fine SBMs. To overcome the limitations of the Aramco method, it was extended by introducing a dedicated software driven laser particle size analyzer that can measure the PSD of all grades of SBMs quickly and accurately. This paper describes the Extended Aramco Method and its application in various SBMs evaluations to select the superior and reject the inferior for high performance drill-in fluid design. Experimental results demonstrate the universal application of the Extended Aramco Method and its usefulness in SBM performance evaluation for superior fluid formulations and non-damaging drilling operations.

Different index parameters are used for quick assessment of mechanical properties of rocks in civil, soil and rock mechanical applications. These index parameters provide valuable information regarding material toughness, abrasion resistance, durability, strength, etc under different forces of interactions and environmental conditions. The sized bridging materials (SBMs) used in drill-in fluid design belongs to rock family and thus any rock mechanical parameters such as UCS, tensile strength, shear strength, etc can be used for mechanical characterization of SBMs to select the best and reject the worst. However, due to granular size of the SBMs with a typical particle size of below 2000 microns, the conventional rock mechanical parameters are not applicable for assessing the toughness and durability of SBMs. Hence, an appropriate index parameter is needed to assess the toughness and durability of SBMs to select the best SBMs for superior drill-in fluid formulation. This paper describes an index parameter defined as Bridging Material Stability Index (BMSI) for quick and reliable assessment of the toughness and durability of SBMs.Empirical results indicate strong relation of the index parameter with the quality of the SBMs and thus provide a quantitative means for quality control and quality assurance of SBMs. Statistical analyses of the coefficient of variation of BMSI indicate significantly lower coefficient of variation compared to common rock mechanical parameters such as compressive strength, tensile strength and shear strength parameters.The application of the index parameter will allow selecting the best and rejecting the worst SBMs for superior drill-in fluid formulations and thus expected to play a pivotal role in reducing formation damage and enhancing well productivity.

In order to accelerate the development, early uptake and deployment of new technologies being developed in-house by Saudi Aramco's EXPEC Advanced Research Center (EXPEC-ARC), and technologies being developed in collaboration with industry service providers and academia, Saudi Aramco started the development of a Technology Test Site (TTS) in a producing oil field environment. The TTS, when completed, will be a ‘live field lab’ where many emerging new technologies and innovative ideas can be tested and tried under normal reservoir conditions. To date, six wells have been drilled and completed. Extensive and comprehensive geoscience and engineering data were acquired for detailed reservoir characterization and description; including over 11,000 ft. of core data. The preliminary results from the on-going elaborate data analyses, including dual energy CT (X-ray computed tomography) scan, geomechanical data, and log data yield some intriguing insights into the often ignored non-hydrocarbon bearing Upper Cretaceous and Tertiary formations. The on-going data analyses showed why certain intervals are incompetent to withstand mud weight of 8.33 ppg (fresh water equivalent) while drilling. Attempts are being made to extract requisite information that may help to resolve some of the challenges (e.g. loss circulation while drilling and "near surface" seismic anomalies) frequently encountered across the Tertiary and Cretaceous shallow formations. This paper highlights the value proposition for a ‘live field lab’ technology test site, lessons learned during the first phase of the TTS development, some results of on-going analysis, and some of the best practices that were developed.