Light curing device for curing a liner of a pipeline

1. An apparatus for curing a liner of a pipeline, the liner including a resin which is curable by exposure to electromagnetic radiation of a specific wavelength or a specific wavelength range, the apparatus comprising:

a housing defining opposite first and second ends, an outer wall, and an inner wall defining a substantially unobstructed through-going passage extending longitudinally through the housing from the first and toward the second end;

a power supply wire for the supply of electrical power to the apparatus;

a plurality of light emitting diodes configured to irradiate electromagnetic radiation of the specific wavelength or the specific wavelength range, the plurality of light emitting diodes being positioned about the housing, the plurality of light emitting diodes being connected to the power supply wire;

wherein the plurality of light emitting diodes are connected in thermal conductive relationship to heat dissipating elements at the inner wall of the housing in the through-going passage of the housing for allowing a stream of cooling fluid to pass through the passage for dissipating heat from the heat dissipating elements and cooling the light emitting diodes;

wherein the housing defines an innermost wall dividing the substantially unobstructed through-going passage into an inner passage centrally located within the substantially unobstructed through-going passage and extending substantially between the first and second ends, and, an outer

passage defined between the inner wall and the innermost wall and coaxially enclosing the inner passage, and

wherein said housing is closed at said second end and said through-going passage defines a flow reversing chamber at said second end for establishing fluid communication between said first passage and said second passage.

2. The apparatus of claim 1 , wherein:

the housing defines a centrally located inlet for receiving pressurized gas, the inlet being in fluid communication with the inner passage at the first end.

3. The apparatus of claim 1 , wherein:

the housing defines an outlet at the first end, the outlet being in fluid communication with the outer passage.

4. The apparatus of claim 3 , wherein:

the outlet is located off center or circumferentially about the housing.

5. The apparatus of claim 2 , wherein:

the housing defines an outlet at the second end, the outlet being in fluid communication with the outer passage and the inner passage at the second end.

6. The apparatus of claim 5 , wherein:

the housing defines a secondary inlet located off center or circumferentially about the housing at the first end, and in fluid communication with the outer passage.

7. The apparatus of claim 6 , wherein:

the innermost wall defines a nozzle adjacent the outlet or adjacent the inlet, the nozzle defining a minimum flow area of the inner passage for establishing a jet from the inner passage towards the outlet.

8. The apparatus of claim 1 , further comprising:

an outer cover extending between the opposite first and second end, enclosing the outer wall and establishing an outermost passage in fluid communication with the outer passage and/or forming part of the outer passage.

9. The apparatus of claim 2 , wherein:

the cooling fluid inlet is connected to a flexible polymeric sheathing tube defining a curved outer surface and being capable of supplying cooling fluid to the cooling fluid inlet.

10. The apparatus of claim 9 , wherein:

the polymeric sheathing tube is configured for pushing and pulling the apparatus.

11. The apparatus of claim 9 , wherein:

the polymeric sheathing tube comprises communication wirings for providing communication with the apparatus.

12. The apparatus of claim 11 , further comprising:

a sensor in communication with the communication wirings.

13. The apparatus of claim 9 , wherein the apparatus further comprises:

a drive mechanism coupled to a seal installation device or to a tubing connected to the seal installation device, the drive mechanism comprising:

a first pair of rollers located on opposite sides of the sheathing tube, each roller of the first pair of rollers defining a concave peripheral surface contacting the curved outer surface of the sheathing tube and defining a curvature corresponding to the curved outer surface of the sheathing tube, the first pair of rollers being mutually interconnected; and

a second pair of rollers located on opposite sides of the sheathing tube and adjacent the first pair of rollers, each roller of the second pair of rollers defining a concave peripheral surface contacting the curved outer surface of the sheathing tube and defining a curvature corresponding to the outer surface of the sheathing tube, the second pair of rollers being mutually interconnected.

14. The apparatus of claim 1 , wherein:

the plurality of light emitting diodes are connected in thermal conductive relationship to further heat dissipating elements at the innermost wall of the housing in the inner passage of the housing for allowing a stream of cooling fluid to pass through the inner passage for dissipating heat from the additional heat dissipating elements and cooling the light emitting diodes.

15. The apparatus of claim 1 , wherein:

the outer wall of the housing comprises a set of curved or planar surface elements, each of the curved or planar surface elements extending longitudinally between the first and the second ends of the housing, the surface elements being of identical configuration.

16. The apparatus of claim 15 , wherein:

the plurality of light emitting diodes is arranged at the curved or planar surface elements for allowing irradiation of the electromagnetic radiation radially from the curved or planar surface elements.

17. The apparatus of claim 16 , wherein:

each of the curved or planar surface elements constitutes an outer surface component of a housing element, the housing element comprising a finned heat dissipation element arranged opposite to the curved or planar surface element.

18. The apparatus of claim 1 , further comprising:

first and second end housing components protruding beyond the outer wall of the housing and serving to prevent physical contact between the outer wall of the housing and the liner.

19. The apparatus of claim 1 , further comprising:

co-operating first and second connectors provided at the first and second ends, respectively, configured for allowing the apparatus to be connected to an identical apparatus for providing a system of apparatuses comprising a number of apparatuses.

20. The apparatus of claim 19 , wherein the first connector of the apparatus and the second connector of any of the identical apparatuses, when joined together, form a cardanic linking or a ball-and-socket joint between any two apparatuses of the assembly.

21. A method of curing a liner of a pipeline, the liner including a resin, which is curable by exposure to electromagnetic radiation of a specific wavelength or a wavelength range, the method comprising:

providing an apparatus according to claim 1 ;

moving the apparatus within the liner while supplying a stream of cooling fluid through one of the inner passage and the outer passage;

supplying electrical power to the light emitting diodes through the pair of power supply wires for irradiating electromagnetic radiation of the specific wavelength or the specific wavelength range onto the liner for causing the resin to cure; and

adjusting the velocity of movement of the apparatus through the liner.

22. The apparatus of claim 1 wherein the light emitting diodes are substantially evenly distributed about the housing.