| 摘要 |
A well tractor (32) for use In inserting a bottom hole assembly (28) into a wellbore (14), the well tractor (32) including a tractor body (38), and two or more wheels (36) connected to the tractor body (38) by pivot arms (44) and having a retracted position and a deployed position, the at least two wheels (36) moveable between the retracted and deployed positions by hydraulic cylinders (45) attached to the pivot arms (44). The well tractor (32) further includes a track (34) creating a loop around at least two wheels (36) and engaged with the wheels (36), so that when the wheels (36) rotate, the track (34) also rotates around the wheels (36). When the wheels (36) are in the retracted position, the track (34) is maintained in close proximity to the tractor body (38), and when the wheels (36) are in the deployed position, the track (34) extends radially away from the tractor body (38) and into contact with surfaces of the wellbore (14). |
