Helical buckling is expected to occur inhorizontal/deviated extended reach wells. Eventually, the cumulative frictioncan lead to helical lock-up. The best solution is agitator/extended reach tool, it creates gentle pressure pulses that have been proven to help complete coil tubing operations in extended reach wellbores, the pressure pulses create axial movement in the work string which in turn reduce the friction between the work string and the wellbore. This movement helps prevent lock up.
Built around a compact positive displacement motor, the CT Agitator actuates a rotating valve mechanism. The motor’s rotor pushes an upper movable valve plate with an offset hole to swing back and forth over a fixed plate that has a centered hole. Full alignment of the two holes opens up the largest possible flow path, while subsequent rotation partially blocks the stationary hole and narrows fluid passage space. Fluctuations in this flow cross-section produce cyclic pressure pulses radiating outwards from the tool, which overcome static friction between the tool and wellbore surfaces.
