Apparatus to allow a coiled tubing tractor to traverse a horizontal wellbore
AssigneeBJ Services Company
InventorJohn Gordon Misselbrook
Life of this patent
Estimating the term…
Abstract
Apparatus and methods are provided for removing sand and/or other fill material located in a wellbore ahead of a coiled tubing tractor and displacing the material behind the tractor. More particularly, the apparatus and methods of the present invention allow a coiled tubing tractor to drive forward in a wellbore by removing fill material in front of the tractor thereby allowing the wheels or traction pads of the tractor to remain in contact with the wellbore.
Claims17
A method of moving a coiled tubing tractor through a wellbore containing sand, the method comprising the steps of:
- running a coiled tubing tractor assembly on coiled tubing into the wellbore, the tractor assembly comprising one or more forward facing jet nozzles, the tractor, a suction inlet ahead of the tractor and a jet pump behind the tractor, the jet pump being in fluid communication with the suction inlet;
- removing a sand bed ahead of the tractor by fluidizing the sand particles with the one or more forward facing nozzles to create a sand-ladened slurry;
- sucking the sand-ladened slurry through the suction inlet;
- pumping the sand-ladened slurry via the jet pump past the trailing end of the tractor assembly;
- and
- driving the tractor through the portion of the wellbore that previously contained the sand bed.
A coiled tubing tractor assembly comprising:
- one or more forward facing jet nozzles operable to fluidize sand beds ahead of a coiled tubing tractor;
- the coiled tubing tractor having a tractor body, a fluid passageway for delivering fluid to the one or more jet nozzles and a return fluid passageway;
- a suction inlet between the one or more jet nozzles and the tractor;
- and
- a jet pump located behind the tractor wherein the return fluid passageway provides fluid communication between the suction inlet and an inlet port on the jet pump, the jet pump being operable to pump the fluidized sand past the trailing end of the tractor assembly.
A method of driving a coiled tubing tractor through a wellbore containing sand, the method comprising the steps of:
- providing a coiled tubing tractor assembly on a coiled tubing in a wellbore, the tractor assembly comprising one or more forward facing jet nozzles, the tractor and a jet pump;
- circulating a power fluid down the coiled tubing to the jet pump wherein a portion of the power fluid is diverted through the tractor and out the one or more forward facing jet nozzles to create one or more jet streams in the wellbore ahead of the tractor assembly;
- fluidizing the sand in the wellbore with the one or more jet streams;
- sucking the fluidized sand through a suction inlet located in front of the tractor and returning the fluidized sand to the jet pump;
- pumping the fluidized sand past the trailing end of the tractor assembly with the jet pump;
- and
- driving the tractor through the jetted section of the wellbore.
Dependencies are inferred from the claim text.