Well tractor gaining ground
Increasing use is being made of Statoil's well tractor. As a result of this technology, annual savings for the group are expected to reach NOK 50 million.
According to Statoil staff engineer Tommy Byskov, the well tractor has led to reductions in time and costs for well operations, which have also become safer and more straightforward. Since the first tests were performed in 1996 and up to April, the tractor has covered a distance of 300 kilometres in horizontal wells.
Developed over three years in cooperation with Welltec of Denmark and Norwegian Maritime Well Service, the 6.5 metre-long vehicle is used to insert various instruments into wells. An electric cable supplies it with energy. The vehicle pushes the instruments into the horizontal section of the well, which may extend several kilometres. Other more cumbersome methods such as coiled tubing and snubbing had to be used previously.
The equipment is used for plugging, perforation and logging in production wells. Operators can thus cost-effectively seal off water-producing zones, open up new oil-producing layers or monitor downhole pressure and temperature.
The well tractor is currently on view at Statoil's head office.