Analysis of low frequency axial drilling dynamics from block velocity input to surface weight on bit (SWOB) or differential pressure outputs, shows significant regional variation. This range in dynamics poses a robustness challenge for automated drilling control systems. Many factors influence drilling dynamics such as pipe stiffness, mud properties, tortuosity, friction, bit design, and BHA geometry.
A simple analytic model representing axial drilling dynamics is described and compared to a finite element drilling model and to drilling data. The analytic model shows that axial drilling dynamics may be represented by a first-order transfer function with a time constant dependent on axial stiffness and drillabillity. Reach out to us here for the full tech paper: https://www.helmerichpayne.com/resources/technical-publications/modeling-of-axial-rotary-drilling-dynamics-as-a-step-towards-drilling-automation or contact us here: https://www.helmerichpayne.com/contact.
A million dollar bounty, underground assassins, torture-it's all in a days work for assassin Jessie Wright.
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Molded into an assassin by the one who killed her parents, Jessie defies orders and goes rogue. Now with a bounty on her head, her only chance of survival may be with a man who's reputation is worse than her own.
Violence, Assault, Swearing.