The use of real-time mechanics and dynamics measurements has expanded and evolved significantly in the last thirty years, enabling the safe and reliable drilling of complex wells. Unfortunately, these measurements are poorly defined, which inhibits straightforward analysis and hinders development of models, simulators and automation applications. Adoption of open measurement guidelines will provide the transparency required to improve the value of existing measurements and accelerate the development and adoption of enhanced applications and automation.
Mechanics and dynamics measurements currently can be processed and transmitted from downhole in near real-time and then merged with other surface measurements. Optimization of the drilling process uses these combined measurements for monitoring, advising and control, thereby delivering a quality borehole as planned, in a safe and reliable fashion. Processing includes real-time filtering, mathematical modeling, and simulation, which are significant parts of any systems approach.
There are currently multiple methods used to quantify downhole and surface vibrations, displacements, and forces. Tools use dissimilar sensor and processing configurations, so they yield significantly different data. Regrettably, these different measurements are given the same name, and published descriptions often do not include the details required to understand and properly utilize the data. Examples of key information include sensor characteristics, sensor arrangement, bandwidth, and signal processing. Guidelines are suggested to resolve this state of confusion, including: terminology describing each drilling mechanics and dynamics sensor, configuration, and measurement; and metadata describing how a data value is derived, filtered, processed, transmitted and stored.
This paper examines and defines drilling mechanics and dynamics measurements. It recommends measurement practices and good processing techniques of these measurements, with examples, and presents a recommended open measurement framework. Adoption of this framework will resolve the current state of confusion and uncertainty, enable all parties to develop monitoring, advising and control applications that use these data, and help lower well costs and improve borehole quality.