RIASSUNTO
When configuring tractor assemblies for highly deviated or horizontal conveyance, the tractor power required to deliver the conveyed passenger tool to the target well depth is determined by the weight of the deployed cable and payload, the tortuosity of the well trajectory, and the extent of the target depth. Until now, the tractor toolstring needed to be configured accordingly before being run in hole. Conveyance speed is compromised for the maximum power requirements expected to ensure the tractor is capable of delivering the payload to the target depth.
Having the ability to adjust the power versus speed on command allows the tractor to be optimized to deliver the highest speed in the earlier parts of the well where maximum power is not required. In the deeper portions, or where the well becomes more tortuous, the tractor can be controlled to provide maximum power and ensure the target depth is achieved. Real time control delivers considerable reductions in total conveyance operating time. This is achieved by independently controlling the various drive sections to deliver the optimum speed/power configuration per well section.
There have been more than seventy jobs completed to date utilizing selective functionality across a variety of US land tractor conveyance operations. The jobs have been performed with a range of electric line companies while servicing numerous exploration and production (E&P) operators. Examples include record wells with lateral lengths requiring over 15,000 ft of tractoring. The application of this in-well, real-time adjusted optimization has resulted in tractor conveyance time savings of over 40%. In addition to the efficiency gains, there has also been a reduction in operational risk due to less time spent in hole tractoring.
Selective tractor functionality is commercially available from one provider at the time of writing, but it is quickly setting standards for all tractor conveyance providers.