HEATING CABLE FOR EXTRACTION PIPES OF VISCOUS HYDROCARBONS OR PARAFFINIC IN CONVENTIONAL WELLS AND TYPE TIGHT WELLS, VERTICAL OR DIRECTIONAL, WITH FLOODED ANNULAR IN CASUAL OR PERMANENT FORM, SUITABLE FOR USE BETWEEN LOW AND HIGH FLUID PRESSURES RANGES

Abstract

The present invention relates to a heating cable for extraction pipes of viscous hydrocarbon or paraffinic in conventional wells and tight type wells, with flooded ring in eventual or permanent cases, suitable for use between low and high fluid pressure ranges. The cable, flat type with parallel electric conductors, is also suitable for use in both vertical and directional wells with high operational flexibility in a wide range of variables. Each of the electric conductors (2) is covered by a primary insulation layer (3), and the set of conductors is monolithically coated by a main insulating layer (4) made of fluoropolymer material resistant to the high pressure of the surrounding fluid. Outside of the main insulating layer (4), the structure of the cable is complemented with an external shield (5) defined by a thin metallic material layer.

Claims

1-4. (canceled)

5. A heating cable for a extraction pipe of viscous hydrocarbon or paraffinic in a well, the heating cable comprising: a thermo conductive conduit adapted to be secured to the extraction pipe; a flat cable having an inside cavity; electric conductors located inside the cavity of the flat cable, the electric conductors are arranged in parallel in respect to each other, the electric conductors are separated from each other by a space; an insulation layer independently wrapping each one of the electric conductors, the insulating layer is made of a single insulating material; a monolithic fluoropolymer material filling the inside cavity of the cable, the space between the electric conductors, and surrounding each one of the single layers; and a metallic shield surrounding the monolithic fluoropolymer material, the metallic shield has a shape of a ribbon and is wrapped on the cable in a spiral form; wherein the flat cable passes through the thermo conductive conduit that is secured to the extraction pipe.

6. A heating cable for a extraction pipe of viscous hydrocarbon or paraffinic in a well, the heating cable consisting of: a thermo conductive conduit adapted to be secured to the extraction pipe on the well; a flat cable having an inside cavity; electric conductors located inside the cavity of the flat cable, the electric conductors are arranged in parallel in respect to each other, the electric conductors are separated from each other by a space; an insulation layer independently wrapping each one of the electric conductors, the insulating layer is made of a single insulating material; a monolithic fluoropolymer material filling the inside cavity of the cable, the space between the electric conductors, and surrounding each one of the single layers; and a metallic shield surrounding the monolithic fluoropolymer material, the metallic shield has a shape of a ribbon and is wrapped on the cable in a spiral form; wherein the flat cable passes through the thermo conductive conduit; and wherein the electric conductors are multifilament electric conductors.

7. A heating cable for extraction pipes of viscous hydrocarbon or paraffinic in a well, the heating cable comprising: a thermo conductive conduit adapted to be secured to the extraction pipe; a flat cable having an inside cavity; electric conductors located inside the cavity of the flat cable, the electric conductors are arranged in parallel in respect to each other, the electric conductors are separated from each other by a space; an insulation layer independently wrapping each one of the electric conductors, the insulating layer is made of a single insulating material; a monolithic fluoropolymer material filling the inside cavity of the cable, the space between the electric conductors, and surrounding each one of the single layers; and a metallic shield surrounding the monolithic fluoropolymer material, the metallic shield has a shape of a ribbon and is wrapped on the cable in a spiral form; wherein the flat cable passes through the thermo conductive conduit that is secured to the extraction pipe; and wherein the electric conductors includes three electrical conductors.

8. The heating cable according to claim 5, wherein the thermo conductive conduit secured to a rod located inside the extraction pipe.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] For greater clarity and understanding of the present invention, it is illustrated in several figures where it is represented according to the preferred embodiments, for example, where:

[0014] FIG. 1 is a cross-sectional view of the heating cable.

[0015] FIG. 2 is a partial cross-sectional perspective view of a section of the heating cable.

[0016] FIG. 3 shows, as an example of application of the heating cable, a section of the hydrocarbons extraction pipe on which are fixed the thermo conductive conductors in which interior extends the cable.

DETAILED DESCRIPTION OF THE INVENTION

[0017] In FIGS. 1 and 2 can be seen that the heating cable object of the present invention, designated with the general reference number 1, is a flat cable which presents lines of electrically conductive conductors 2 parallel to each other, each one of which is covered by a primary insulation layer (3). The conductor set (2) is monolithically coated by a main insulating layer (4) of fluoropolymer material which is resistant to the high pressure of the surrounding fluid. Outside this main insulating layer, the structure of the cable is complemented by external shielding (5) defined by a thin layer of a metallic material which, by example, can be defined by a ribbon placed by following a spiral wrapping form.

[0018] On the example of the preferred embodiment, which is described and illustrated, the electrical conductors 2 are of the multifilament type, and the cable 1 includes three lines of conductors 2 which correspond to each one of the phases of the three-phase power applied.

[0019] FIG. 3 shows a typical hydrocarbons extraction pipe 6 which is placed in a production well, on which are fixed, heat exchangers and thermo conductive metallic conduits 7, through support devices having anchors 8 and clamps 9. Throughout the conduits 7, the heating cable 1 of the present invention is extended.

[0020] Optionally, according to an alternative use of the cable 1, in the practice, the thermo conductive conduits 7 can be attached, for example, to a rod located in the interior of the production pipe 6 in position substantially coaxial with the mounting and fastening devices. In this way, the thermo conductive conduits 7 with the cable 1 inside, will define a direct heat exchange medium with the fluid transported by the production pipe, it is worthy to say that without the duct 5 being in contact with the inner wall of the production pipe, but directly with the circulating fluid within it.

[0021] Having thus particularly described and determined the nature of the present invention and how it is to be realized, is claimed, in exclusive the right and property.