Patent attributes
An internal tractor system useful for advancing and withdrawing a tubular body within a wellbore is provided. Preferably, the wellbore includes a horizontal section, and the internal tractor system is used to advance a string of coiled tubing or a flexible jetting hose along the horizontal section. The internal tractor system includes an elongated carrier body. The carrier body defines a wall forming a plurality of radially-disposed prongs, and a passageway within the wall. The passageway is dimensioned to closely receive the tubular body along the length of the carrier body to prevent buckling. The internal tractor system also includes a wiring chamber housing electrical wires or data cables within one of the plurality of prongs, and at least one pair of grippers residing within opposing prongs. Each gripper is configured to engage the tubular body when rotatably actuated. A method of advancing a tubular body along a wellbore, using the internal tractor system is also provided.