Mechanical Specific Energy (MSE): Claims and Implications – Facts, Fallacies, and Pitfalls (Part-2)

Abstract Mechanical Specific Energy (MSE) is used extensively in the drilling industry for numerous purposes, most commonly as a strategy for drilling optimization. Additionally, MSE is used for determination of rock hardness, development and assessment of drilling parameters roadmaps, benchmarking, and drilling efficiency calibrations. MSE, in addition to being used for identification and remediation of drilling dysfunctions, is also utilized in completions design optimization for unconventionals. These applications of MSE are important in all drilling operations, regardless of asset class, from exploration through development. MSE deployment is grounded in several strongly held positions, with associated implications. In Part-1 (SPE 212508) of this critical conversation, which attracted intense industry debate, it was revealed that most MSE claims lack factual validations, and that the assertions had numerous fallacies and pitfalls. These findings, which established limitations and inefficiencies in MSE deployment, are critical for the industry. Most importantly, awareness of MSE shortfalls will ensure development of effective, and verifiable solutions for drilling efficiency improvement. MSE initiatives and claims must be held true, supported by operational objectives, and ratified by physics and drilling mechanics principles. This follow-up paper identifies additional MSE deficits, with primary focus on its claims. These assertions, as will be discussed include the following – performance benchmarking, drilling efficiency quantification and improvement, identification of performance risks and limiters, recognition, and remediation of drilling dysfunctions – regardless of asset class and/or application type. Fallacies and pitfalls associated with these claims will be identified and analyzed, through appropriate physics-based processes, where the erroneous implications of these claims, will be identified and discussed. In addition to supporting these positions with appropriate field data, a new systematic "Five-Step" process (AIVReC) for discussing dysfunctions will be introduced. It is worth noting that this paper’s positions promote development of appropriate workflows for data analytics and drilling automation processes. These needs cannot be achieved with current MSE positions and claims, because of the numerous fallacies and pitfalls.