Welltec invented and deployed the world’s first Coiled Tubing Well Tractor in 1993 enabling operators to pull CT into the well to extend the reach and improve operations. Being able to reach total depth before stimulating makes it possible to realize the full production potential of the well providing a higher productivity index.

Traditionally, CT will bullhead acid from the point of lock-up; however, the placement strategy can be implemented more effectively by stimulating from the toe while pulling the CT out of the well. This is also true for other applications where fluids are needed to be spotted such as cleaning, washing, etc.

Despite being a prevalent intervention method, conventional CT faces a number of mechanical limitations in highly deviated wells, limiting its reach. The phenomenon, known as “lock-up”, is brought on by frictional forces. As CT runs into the well, drag continues to increase, the weight begins to drop off, and finally the force of friction overcomes the movement of the CT into the well. As an alternative, the CT Well Tractor uses mechanical means to exert a force on the casing or formation and pull itself and its payload deeper into the wellbore thereby extending the reach of CT. Increasing force comes from increasing the tractor size, and/or the number of wheel sections. When the required depth cannot be reached during pre-job simulations, a CT tractor should be considered.

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