DOWNHOLE DEEP TUNNELING TOOL AND METHOD USING HIGH POWER LASER BEAM

• US 20140360778A1
• Filed: 06/10/2013
• Published: 12/11/2014
• Est. Priority Date: 06/10/2013
• Status: Active Grant

• Current Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Original Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Inventors: Batarseh, Sameeh Issa
• Granted Patent: US 9,217,291 B2
• Time in Patent Office: Days
• US Class Current: 175/17
• CPC Class Codes: E21B 7/046 horizontal drilling drilling with mechanical conveying means E21B7/003
• CPC Class Codes: E21B 7/14 Drilling by use of heat, e.g. flame drilling
• CPC Class Codes: E21B 7/15 of electrically generated heat

Abstract

A downhole laser tool for penetrating a hydrocarbon bearing formation includes a laser surface unit to generate a high power laser beam, a fiber optic cable to conduct the high power laser beam from the laser surface unit to a rotational system that has a rotational head which includes a focusing system and a downhole laser tool head, the focusing system includes a beam manipulator, a focused lens, and a collimator, the downhole laser tool head includes a first cover lens to protect the focusing system, a laser muzzle to discharge the collimated laser beam from the downhole laser tool head into the hydrocarbon bearing formation, a fluid knife to sweep the first cover lens, a purging nozzle to remove dust from the path of the collimated laser beam, a vacuum nozzle to collect dust and vapor from the path of the collimated laser beam.

Claims

1. A downhole laser tool for penetrating a hydrocarbon bearing formation, the downhole laser tool comprising:

a laser surface unit configured to generate a high power laser beam, the laser surface unit in electrical communication with a fiber optic cable, the fiber optic cable configured to conduct the high power laser beam, the fiber optic cable comprising an insulation cable configured to resist high temperature and high pressure, a protective laser fiber cable configured to conduct the high power laser beam, a laser surface end configured to receive the high power laser beam, a laser cable end configured to emit a raw laser beam from the fiber optic cable;

an outer casing placed within an existing wellbore wherein the existing wellbore extends within a hydrocarbon bearing formation;

a hard case placed within the outer casing, wherein the fiber optic cable is contained within the hard case; and

a rotational system positioned within the outer casing, the rotational system comprising a rotational casing coupled to the end of the hard case, a rotational head extending from the rotational casing, wherein the rotational system is configured to rotate around the axis of the hard case,

wherein the rotational head comprises a focusing system configured to direct the raw laser beam, and a downhole laser tool head configured to discharge a collimated laser beam into the hydrocarbon bearing formation;

wherein the focusing system comprises a beam manipulator configured to direct the raw laser beam, a focused lens configured to create a focused laser beam, and a collimator configured to create the collimated laser beam,

wherein the beam manipulator is positioned proximate to the laser cable end of the fiber optic cable, the focused lens is positioned to receive the raw laser beam, the collimator is positioned to receive the focused laser beam; and

wherein the downhole laser tool head comprises a first cover lens proximate to the focusing system, a laser muzzle positioned to discharge the collimated laser beam from the downhole laser tool head, a fluid knife proximate to the laser muzzle side of the first cover lens, a purging nozzle within the downhole laser tool proximate to the laser muzzle, a vacuum nozzle proximate with the laser muzzle, and a temperature sensor adjacent to the laser muzzle,

wherein the first cover lens is configured to protect the focusing system, the fluid knife is configured to sweep the first cover lens, the purging nozzle is configured to remove dust from the path of the collimated laser beam, the vacuum nozzle is configured to collect dust and vapor from the path of the collimated laser beam.

2. The downhole laser tool of claim 1, further comprising stabilizing pads attached to the hard case and configured to hold the hard case in place relative to the outer casing.

3. The downhole laser tool of claim 1, wherein the beam manipulator is a reflector mirror.

4. The downhole laser tool of claim 1, wherein the beam manipulator is a beam splitter.

5. The downhole laser tool of claim 1 further comprising a second cover lens positioned proximate to the first cover lens between the first cover lens and the fluid knife.

6. The downhole laser tool of claim 1, wherein the focused lens is positioned proximate to the laser cable end of the fiber optic cable, the collimator is positioned to receive the focused laser beam, the beam manipulator is positioned to receive the collimated laser beam.

7. The downhole laser tool of claim 1 further comprising multiple rotational heads extending from one rotational casing.

8. The downhole laser tool of claim 1 further comprising multiple rotational systems.

9. The downhole laser tool of claim 1, wherein the downhole laser tool head has a tapered laser muzzle.

10. The method for penetrating a hydrocarbon bearing formation with a downhole laser tool, the method comprising the steps of:

extending a downhole laser tool into an existing wellbore, the downhole laser tool comprising a laser surface unit connected to a fiber optic cable, a hard case surrounding the fiber optic cable, an outer casing surrounding the hard case, a rotational system positioned within the outer casing, and a rotational head extending from the rotational system,

wherein the rotational head comprises a focusing system and a downhole laser tool head,

wherein the focusing system comprises a beam manipulator, a focused lens, and a collimator,

wherein the downhole laser tool head comprises a first cover lens, a fluid knife, a purging nozzle, a vacuum nozzle, and a temperature sensor;

operating the laser surface unit in a run mode, wherein the fiber optic cable connected to laser surface unit conducts a raw laser beam to the focusing system of the rotational head of the rotational system during the run mode,

wherein the run mode concludes when a desired penetration depth is reached by a collimated laser beam;

emitting the raw laser beam from the fiber optic cable to the beam manipulator, wherein the beam manipulator redirects the path of the raw laser beam toward the focused lens;

focusing the raw laser beam in the focused lens to create a focused laser beam;

collimating the focused laser beam in the collimator to create a collimated laser beam;

passing the collimated laser beam through the first cover lens;

sweeping the first cover lens with the fluid knife;

purging the path of the collimated laser beam with the purging nozzle during the run mode of the laser surface unit;

sublimating the hydrocarbon bearing formation with the collimated laser beam during the run mode of the laser surface unit to create a tunnel to the desired penetration depth; and

vacuuming the dust and vapor with the vacuum nozzle during the run mode of the laser surface unit.

11. The method of claim 10, further comprising the step of:

rotating the rotational system to target a new area of the hydrocarbon bearing formation.

12. The method of claim 10, wherein the rotational system comprises multiple rotational heads.

13. The method of claim 10, wherein the run mode comprises a cycling mode,

wherein the cycling mode further comprises the step of cycling the laser surface unit between on periods and off periods,

wherein the raw laser beam is conducted from the laser surface unit to the focusing system during the on period.

14. The method of claim 13, further comprising the steps of

purging the path of the collimated laser beam with the purging nozzle during the on period;

and

vacuuming the dust and vapor with the vacuum nozzle during the off period.

15. The method of claim 10, wherein the run mode comprises a continuous mode,

wherein the laser surface unit operates continuously until desired penetration depth is reached.