Abstract
Method which is intended for producing an endless semi-finished product and having the following steps: feeding a silicone tube and a separate internal conductor, wherein the internal conductor runs in a first interior space formed by the silicone tube; encasing the fed silicone tube by production of an endless fibre tube, which encloses the silicone tube from the outside. The silicone tube is expanded so that a gap is formed between the silicone tube and the endless fibre tube. A matrix material is feed into the gap connecting the silicone tube and the endless fibre tube by virtue of the matrix material being cured.
Claims
1. A method for producing a continuous semifinished product, which comprises: supplying a silicone hose and a separate inner conductor, wherein the inner conductor runs in a first interior space formed by the silicone hose; encasing the supplied silicone hose by producing a continuous fiber hose that encloses the silicone hose on the outside; spreading open the silicone hose so that a gap is formed between the silicone hose and the continuous fiber hose; supplying a matrix material into the gap; and bonding the silicone hose and the continuous fiber hose by hardening the matrix material.
2. The method as claimed in claim 1, which comprises: producing the silicone hose by extrusion, and introducing the separate inner conductor into the first interior space formed by the silicone hose.
3. The method as claimed in claim 1, wherein the continuous fiber hose is produced by weaving on a circular loom.
4. The method as claimed in claim 3, wherein the continuous fiber hose comprises thermoplastic continuous fibers.
5. The method as claimed in claim 4, wherein the silicone hose and the continuous fiber hose are bonded to one another by heating at least the continuous fiber hose, with the result that the thermoplastic continuous fibers of the continuous fiber hose shrink, the gap is reduced as a result, and the matrix material is hardened.
6. The method as claimed in claim 1, wherein a liquid coating material is applied in an annular manner to the outer side of the continuous fiber hose which moves in the conveying direction (F), and in that the liquid coating material is subsequently hardened.
7. The method as claimed in claim 1, wherein the fibers comprises at least one of the following fibers: polyester, polyamide, polyethylene and aramid.
8. A device for producing a continuous semifinished product, comprising: a conveying device for supplying a silicone hose and an inner conductor arranged inside the silicone hose; a bonding device for bonding a plurality of fibers to form a continuous fiber hose, and for encasing the supplied silicone hose with the continuous fiber hose; a spreading device for opening out the silicone hose and for reducing a gap between the continuous fiber hose and the silicone hose; a supplying device for supplying a liquid bonding agent into the gap; and a crosslinking device for crosslinking the bonding agent and for bonding the silicone hose to the continuous fiber hose.
9. The device as claimed in claim 8, comprising: an extrusion device for producing the silicone hose and for inserting the inner conductor into the silicone hose.
10. The device as claimed in claim 8, wherein the bonding agent comprises silicone, polyurethane or polyurea.
11. A continuous semifinished product produced by a method as claimed in claim 1.
12. A downhole heat exchanger having a continuous semifinished product as claimed in claim 11, for use in geothermal technology.
13. A borehole reinforcement having a continuous semifinished product as claimed in claim 11, for use in civil engineering when groundwater is present.
14. A restoration pipe having a continuous semifinished product as claimed in claim 11, for use as an internal pipe for defective pipelines.
15. A continuous semifinished product or downhole heat exchanger comprising a silicone hose having a first interior space, comprising a separate inner conductor which runs inside the first interior space, and also comprising a continuous fiber hose enclosing the silicone hose on the outside, wherein the silicone hose and the continuous fiber hose are bonded to one another by a hardened matrix material.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] In the drawings which are used to explain the exemplary embodiments:
[0033] FIG. 1 shows a schematic illustration of a device for producing a continuous semifinished product;
[0034] FIG. 2 shows a schematic view of a detail of a device for coating the outside;
[0035] FIG. 3 shows a schematic view of a detail of a longitudinal section through a silicone hose and an outer woven fabric during the mutual bonding process;
[0036] FIG. 4 shows a cross section through FIG. 2 along the sectional line A-A;
[0037] FIG. 5 shows a cross section through a continuous semifinished product which is arranged flat;
[0038] FIG. 6 shows a cross section through a folded continuous semifinished product;
[0039] FIG. 7 shows a side view of a rolled-up continuous semifinished product.
[0040] In principle, identical parts are provided with the same reference signs in the drawings.
WAYS OF IMPLEMENTING THE INVENTION
[0041] FIG. 1 shows a schematic illustration of a device 1 for producing a continuous semifinished product 10. Inside an extrusion device 2, which is schematically illustrated, a silicone hose 12 is produced in a manner known per se from a silicone which is supplied from a silicone reservoir vessel 4 via inlets 4a, 4b. The silicone hose 12 is at that moment inflated by injecting air and subsequently the inflated hose is vulcanized. If the silicone hose 12 were to have a hole during his production process, this would prevent the inflation and the hose would collapse. Consequently, during the production process, it can be easily checked, for example using arranged sensors, whether the silicone hose at most has leakage points, and/or it can be ensured that the silicone hose is fluid-tight. This production method thus ensures that the wall of the silicone hose 12 does not have any permeable points. As illustrated in FIG. 1, an inner conductor 11 is additionally supplied to the extrusion device 2 in such a way that said inner conductor extends along the interior space of the silicone hose 12 produced. The inner conductor 11 is, for example, a woven hose for supplying a fluid into the interior space of the silicone hose 12. The inner conductor 11 could, however, for example also be an electrical conductor, or could additionally for example comprise sensors, it being possible to return the measured data thereof to a control device via the electrical conductor. The silicone hose 12 is conveyed at a velocity V.sub.1 in the conveying direction F.
[0042] The silicone hose 12 and the inner conductor 11 located therein is supplied to a circular loom 3, which is schematically illustrated, using a conveying device 9, which is schematically illustrated. The circular loom 3 interweaves a plurality of supplied warp threads 13c with at least one weft thread 13d in a manner known per se, and therefore a tubular outer woven fabric is formed which forms the continuous fiber hose 13. The continuous fiber hose 13 encloses the silicone hose 12 completely in the circumferential direction, with the result that a tubular continuous semifinished product 10 comprising the inner conductor 11, the silicone hose 12 and the continuous fiber hose 13 leaves the circular loom 3 in the conveying direction F at a conveying velocity V.sub.2.
[0043] As illustrated in FIG. 2, subsequently a coating material 8 located in a dip tank 7 is applied to the outer side of the continuous fiber hose 13 and completely encloses the outer side of the continuous fiber hose 13. The originally liquid coating material 8 is bonded here to the fibers of the continuous fiber hose 13 and subsequently hardens to form a surface coating 8a, the coating material 8 being selected in such a way that it nevertheless remains elastic and flexible after the hardening. A silicone is preferably used as the coating material 8. The continuous fiber hose 13 and/or the tubular continuous semifinished product 10 is illustrated only schematically in FIG. 2, and the surface coating 8a is illustrated as being considerably thicker than it is in reality for better illustration.
[0044] FIG. 3 schematically shows a longitudinal section through the silicone hose 12 and the continuous fiber hose 13, said silicone hose and said continuous fiber hose being located in the circular loom 3, and the uppermost weft thread 13d representing the most current weft thread 13d introduced by the circular loom 3. The external diameter of the continuous fiber hose 13 is substantially determined by the internal diameter of the funnel-shaped circular loom 3 at the edge 3a thereof. In the region of this edge 3a, as illustrated in FIG. 1, the silicone hose 12 is inserted into the continuous fiber hose 13 which is obtained in the region of the edge 3a. In the process, as illustrated in FIG. 3, a gap 14 is formed between the continuous fiber hose 13 and the silicone hose 12. In a particularly advantageous configuration, the silicone hose 12 is spread at least in the region of the edge 3a, in order to keep the gap 14 predictably wide. Proceeding from a second reservoir vessel 5, a matrix material, preferably silicone, is supplied via a feed line 5a to the gap 14 in a manner distributed over the entire circumferential direction, the silicone hose 12 and the continuous fiber hose 13 being conveyed in the conveying direction F, and in the process being supplied to a crosslinking device 6 having an infrared heater 6a. In the process, the bonding agent 5b, which adheres to the outer surface of the silicone hose 12 and to the internal surface of the continuous fiber hose 13, and/or the matrix material supplied is hardened, and therefore the silicone hose 12 and the continuous fiber hose 13 are bonded to one another after the hardening, and advantageously are bonded or adhesively bonded to one another over the entire surface area and along the entire circumferential surface. In an advantageous embodiment, the woven fabric of the continuous fiber hose 13 consists at least partially and advantageously completely of polyester fibers. The crosslinking device 6 heats this woven fabric, for example to a temperature in the range of 120° C., as a result of which the polyester and/or the woven fabric manufactured with polyester fibers shrinks, and therefore the woven fabric in this phase approaches the silicone hose from the outside, so that the woven fabric and the silicone hose come into mutual contact at least at certain points and are mutually adhesively bonded by way of the matrix material. FIG. 3 does not illustrate in detail this gap reduction effect, which proceeds along the crosslinking device 6 in the conveying direction F, and the reduction in diameter of the continuous fiber hose 13.
[0045] FIG. 1 schematically shows an exemplary embodiment of a spreading device 16, which is arranged inside the silicone hose 12 and has a plurality of rolls distributed over the circumference which bear and/or can bear against the inner side of the silicone hose 12 in order to spread the silicone hose 12 from the inside. The spreading device 16 is connected to a holding device, not illustrated, via a suspension 16a. It is advantageously possible to vary and to set the location of the spreading device 16 in the running direction of the silicone hose 12, preferably in such a way that the spreading device 16 is located in the region of the edge 3a, and as a result it is possible to set the width of the gap 14 and preferably also the form of the gap 14 that runs in the conveying direction F.
[0046] FIG. 4 schematically shows a cross section of the finished continuous semifinished product 10 along the sectional line A-A illustrated in FIG. 2. The silicone hose 12 has a first internal cavity 12a. The inner conductor 11 is arranged in a manner running inside the first internal cavity 12a and has a second internal cavity 11a. The continuous fiber hose 13 and the silicone hose 12 are bonded to one another by way of the bonding layer 15. The continuous fiber hose 13 additionally has a surface coating 8a. The silicone hose 12 has an internal diameter D. In an advantageous configuration, the internal diameter D lies in a range of between 10 cm and 100 cm depending on the field of use of the continuous semifinished product 10. In the schematically illustrated cross section according to FIG. 4, the elements silicone hose 12, inner conductor 11, composite layer 15, continuous fiber hose 13 and surface coating 8a are illustrated as being considerably thicker than they are in reality for better clarity.
[0047] FIG. 1 illustrates the production of the silicone hose 12 and the production of the continuous semifinished product 10 in succession. In one possible method, said silicone hose and continuous semifinished product can be produced immediately in succession. In an advantageous method, the silicone hose 12 is produced in a first method step, and after this the silicone hose 12 and the inner conductor 11 arranged therein are temporarily stored, for example by being wound up together onto a storage medium. In a second method step, the temporarily stored silicone hose 12 with the inner conductor 11 is supplied to the circular loom 3, and here the silicone hose 12 is encased with a continuous fiber hose 13 in the circumferential direction and bonded thereto. This division into two method steps has the advantage that different production speeds and/or different conveying velocities V.sub.1, V.sub.2 can be compensated for without problems by virtue of the temporary storage of the silicone hose 12 with the inner conductor 11. It is, however, also possible to operate the first and the second method step at the same conveying velocity, such that the silicone hose 12 produced by the extruder 2 can be returned directly to the circular loom 3, and a continuous production of the silicone hose 12 and the entire continuous semifinished product 10 is possible in this way.
[0048] After the production, the continuous semifinished product 10 is advantageously transferred into a flat state, as illustrated in FIG. 5, such that hardly any fluid or no fluid is located in the first internal cavity 12a of the silicone hose 12 and/or in the second internal cavity 1 la of the inner conductor 11 any more. In a further advantageous method step, the continuous semifinished product 10 is folded at least once, as illustrated in FIG. 6, and subsequently rolled up onto a roll, as illustrated in FIG. 7. A downhole heat exchanger can then be produced in a simple manner in such a way that the continuous semifinished product is cut to a desired length of for example between 50 and 500 m, that a borehole with a corresponding length is produced, and that the tip 10a of the continuous semifinished product 10 which has been cut to length is provided with a fluid-tight closure, for example with what is known as a probe foot. Subsequently, the tip 10a, comprising the probe foot and additionally optionally a possible additional weight, is inserted and lowered into the borehole, until the continuous semifinished product 10 which has been cut to length is substantially lowered in the borehole. After the lowering operation, which is preferably complete, a pressurized fluid is supplied to the inner conductor 11, the consequence of which is that the continuous semifinished product which has been cut to length, in particular the silicone hose 12 and the continuous fiber hose 13 thereof, is unfolded in the borehole. Such an arrangement could already be used as a downhole heat exchanger. However, it is preferable if, after the unfolding in the borehole of the continuous semifinished product which has been cut to length, the inner conductor 11 is removed by being withdrawn, and introduced instead of the inner conductor 11 is a preferably rigid fluid line, which is advantageously thermally insulated with respect to the outside and preferably extends substantially from the inlet of the borehole as far as approximately the fluid-tight closure of the continuous semifinished product 10 which has been cut to length. The inlet of the borehole is understood for example to mean the point at which the borehole enters the ground. It is preferable if at least heat exchanging devices and fluid pumps are arranged in the region in front of the inlet of the borehole. During operation of the downhole heat exchanger, either a fluid that flows inside the fluid line and emerges from the fluid line at the end of the fluid line, preferably in the region of the fluid-tight closure, is supplied via the fluid line, the fluid subsequently flowing back again in the interior space 12a formed between the fluid line and the silicone hose 12 substantially to the inlet of the borehole. The fluid can of course also flow in the opposite direction by the fluid being supplied to the interior space 12a substantially in the region of the inlet of the borehole and preferably flowing as far as the region of the fluid-tight closure within the silicone hose 12, and in this region at the end of the fluid line enters the fluid line, and inside the fluid line is conducted again substantially to the region of the inlet of the borehole.
[0049] In an advantageous configuration, the continuous semifinished product and/or the downhole heat exchanger comprises a silicone hose 12 having a first interior space 12a, comprises a separate inner conductor 11 which runs inside the first interior space 12a, and comprises a continuous fiber hose 13 enclosing the silicone hose 12 on the outside, the silicone hose 12 and the continuous fiber hose 13 being bonded to one another by a hardened matrix material.
[0050] In an advantageous configuration, the continuous semifinished product is prefabricated in such a way that it has a particular length, and that that end of the continuous semifinished product which is to be lowered into the borehole has a fluid-tight closure in that the silicone hose 12 forms a fluid-tight end and in that the end of the continuous fiber hose 13 preferably has an end face which covers the fluid-tight end of the silicone hose 12. It is preferable if a plurality of continuous semifinished products of this type having different lengths are provided, so that a continuous semifinished product with a matching length can be selected from the plurality of continuous semifinished products, depending on a respective borehole depth.
