AUTHOR=Chai Lin , Sun Qiang , Liu Baolin , Tang Feng 

TITLE=Working characteristic research on the mechanical stable platform of the automatic vertical drilling system

JOURNAL=Frontiers in Energy Research

VOLUME=12

YEAR=2024

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2024.1426840

DOI=10.3389/fenrg.2024.1426840

ISSN=2296-598X

ABSTRACT=<p>As a novel technology, the mechanical stable platform can effectively improve the temperature resistance of the automatic vertical drilling system, but its working characteristics are still not yet clear. In this paper, theoretical mechanics is introduced to establish the critical deviation angle model, in order to evaluate the sensitivity of the mechanical stable platform to well deviation. Multi-body dynamics simulation is applied to mutually verify the models and further analyze the effect of vibration. The results show that the critical deviation angle is not only affected by the platform design parameters, but also by the system speed and external vibration. When the system angular velocity is less than the critical angular velocity <inline-formula id="inf1"><mml:math id="m1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi mathvariant="bold-italic">ω</mml:mi><mml:mi mathvariant="bold-italic">c</mml:mi></mml:msub></mml:mrow></mml:math></inline-formula> (3.76 rad/s), the critical deviation angle <inline-formula id="inf2"><mml:math id="m2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:msub><mml:mi mathvariant="bold-italic">α</mml:mi><mml:mi mathvariant="bold-italic">C</mml:mi></mml:msub><mml:mo>′</mml:mo></mml:msup></mml:mrow></mml:math></inline-formula> gradually decreases with the decreasing angular velocity until it approaches the extreme deviation angle <inline-formula id="inf3"><mml:math id="m3" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi mathvariant="bold-italic">α</mml:mi><mml:mi mathvariant="bold-italic">l</mml:mi></mml:msub></mml:mrow></mml:math></inline-formula> (5.1°). The critical deviation angle is jointly affected by the amplitude A and frequency B of torsional vibration. When A&gt;500°/s and B &gt; 8 Hz, its variation range is between the <inline-formula id="inf4"><mml:math id="m4" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi mathvariant="bold-italic">α</mml:mi><mml:mi mathvariant="bold-italic">l</mml:mi></mml:msub></mml:mrow></mml:math></inline-formula> (5.1°) and the critical deviation angle <inline-formula id="inf5"><mml:math id="m5" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi mathvariant="bold-italic">α</mml:mi><mml:mi mathvariant="bold-italic">c</mml:mi></mml:msub></mml:mrow></mml:math></inline-formula> (7.03°). The critical deviation angle is jointly affected by the amplitude E and frequency F of axial vibration, with its value always greater than <inline-formula id="inf6"><mml:math id="m6" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi mathvariant="bold-italic">α</mml:mi><mml:mi mathvariant="bold-italic">c</mml:mi></mml:msub></mml:mrow></mml:math></inline-formula> , but very small range of variation (0.2°). Torsional vibration plays a dominant role in torsional-axial coupled vibration, and the additional effect of axial vibration is relatively small. The results obtained herein are significant for further understanding and improvement of the performance of the mechanical vertical drilling system.</p>