Advanced SoftTorque

Stick-slip mitigation

Advanced Softtorque (AST) is Electroproject’s (EP) newest implementation of soft torque technology. Advanced Softtorque mitigates the negative effects of the frequently arising stick-slip phenomena in oil and gas well drilling.

To do so, the rotation dynamics of the (top)drive in the drilling rig are changed to dampen the torsional vibrations in the drill string in such a way that the drill-bit speed variation is minimized. The settings for the controller to achieve this minimum speed variation of the drill bit are automatically calculated by an embedded optimization program in the AST system.

Advantages of Advanced SoftTorque

Advanced Softtorque finds its strength in the following:

  • Wide control frequency bands to allow damping of all relevant torsion vibration modes of the drill string. This obviates the need to re-tune at different drilling depths as is needed for conventional Softtorque controllers (STRS technology).
  • AST has proven in practice to deliver better torsional vibration mitigation than traditional Softtorque technology, especially in horizontal operations or when a less stiff pipe is used, such as a 4”.
  • Optimizations to minimize the downhole (Bit/BHA) speed fluctuations. These are especially useful for directional drilling operations.

The graph below shows the performance of the AST system during the horizontal section of a drilling operation. The light blue line represents torque on the surface. Once the Softtorque system is switched on, the torque values stabilize due to the mitigation of the drill-string torsional vibrations.

A must-have to improve drill performance

Acknowledged by major contractors and operators as an important asset for gearing up ROP and avoiding trips caused by wear and tear of tools downhole, Advanced Softtorque has been a success from the first implementation in 2012:

  • The ROP is higher.
  • Tool wear is less. Longer drill-bit runs are possible.
  • The torsional vibrations in the drill string are lower, avoiding problems with the wellbore.
  • NPT during directional drilling operations will drop significantly.

All of this, without the need for the driller to continuously engage with the controller, changing settings, or continuously tuning the controller.

Proven benefits of Advanced SoftTorque

Advanced Softtorque has proven, in practice, to provide 50% to 100% more damping for torsional oscillations. It is because of this more aggressive mitigation ability that the general benefits experienced with traditional Softtorque systems during the vertical sections of drilling operations now extend to the more challenging extended reach and horizontal operations.

Additionally, the AST controller is truly agnostic in the sense that it can be used in all AC top drives, independent of the brand or technology used. Between sister rigs, the AST system can even be swapped from one rig to another.

Advanced Softtorque is the intellectual property (IP) of Electroproject, which is the only company besides Shell with IP rights on wide bandwidth stick-slip mitigation controllers. This positions Electroproject as a technology champion.

Real-time performance measurement and tracking

What is the expected performance of EP Softtorque? And how can its performance be evaluated? No drilling conditions are the same. So how can the actual effectiveness of a solution for mitigating slip-stick be measured? Answers to these important questions are given by Electroproject’s Softtorque Assist. Softtorque Assist is a dedicated simulation tool developed by Electroproject. Depending on the top drive specifications and expected drilling operation, the effectiveness of the AST controller can be simulated. The expected performance can then be documented, which guarantees a successful system implementation.