Method of inserting cables in a duct.

A method of pulling cables into a pipe by means of a cable of the transporting flowing medium, which is injected at the proximal end of the tube and flows out at the remote end

A cable of this type is that of EP-A 0,186,753 known Several, in cross-section is relatively small longitudinal channels are held in a large tube cross-section, into which one or more individually buffered optical fibers may be revoked. Because of the smallness of the cross sections of these longitudinal channels for specific measures in the area of ​​the pressure connection for the flowing medium is not required. In many cases it is desirable to either existing pipes with relatively large diameter feed cable (eg 10 cm) or to transfer such simple and universally usable tubes because of the predetermined small cross-sectional area of ​​the longitudinal channels only one pulling very specific light source conductor cores or very allow thinner cable. In addition to the disadvantage that only light source conductor leads can be blown with a relatively small cross-section in such a thin channels, there is also the problem that the range of such systems is limited even at high pressures.

The present invention has for its object to provide a method in which in particular for feeding tubes at any time - possibly even retrospectively - fiber optic cable can be injected easily. This object is achieved in a method of the type mentioned in that which is complete pressure-tight near the end of the tube having a plurality of first sealed entry ports for cables on facing pressure cap that each one of the inlet ducts open and inserted the cable end of a einzuschießenden cable there and by the near-end pressed in turbulent flowing medium to the far end is transported.

At the tubes as such, thus no special requirements need be made in the present process because the pressure cap can be applied whenever necessary. The related to available free cross-section inside the tubes may also, depending on the respective requirements, to be more or less filled and even at different times and possibly with different types of cables. Previously shot-or connected cables interfere with the inward conveyance Another cable is not as long as the pipe cross-section is not significantly reduced by the cable. For example, in a tube of 10 cm internal diameter sure yet about 30 cables are used with an external diameter of the order of 6 mm and each with about 6 light source conductors, so that a maximum of about 180 light source conductor for transmission becomes available. Overall, the pipe cross-section as should a maximum of less than 20%, preferably between a maximum of 10% and 15%, filled with injected cables werden.Das (distant) outlet pipe end remains as of injection open and is appropriately thereafter secured against water ingress, eg. By using a cut-out cover and a sealant or the like.

optic cables are preferred in the invention injected, as they are particularly easy and largely flexible. The cable jackets are the drawing-in - if not already done in time - different to characterize, to facilitate the identification of the cable at the far end of the pipe. Should be a risk that the tube will be destroyed from the outside, a marking over the entire length is advantageous in order to facilitate the identification in the repair work. Such sequential marking can be carried out during the drawing-in, for example, by a simple film printer.

It is expedient to use tension-resistant optical cable, wherein the outer diameter of the corresponding flexible cable should be in a range between 4 mm and 10 mm. The clearance, which provided for the inclusion of optical cable ducts is, advantageously between 5 cm and 10 cm and must be adapted to the diameter and the number of introduced cable.

When using (eg inserted aramid) reinforced optical cable, a normal drawing-are just combined routes with a Einblasprozeß according to the invention through sharply curved sections. In this way very long cable sections are pull-in and blown, e .g. move over a length of 500 m, then einblasend over 500m with auxiliary seam against the pressure port and a further pulling over again 500 m

The inventions and its developments are explained in more detail with reference to drawings:<ul><li>Figure 1 in cross-section a vcrbereitetes for carrying out the process tube end,</li><li>Figure 2 seen a cross-section through the tube of Figure 1 in the direction of the pressure cap and</li><li>3 in a schematic illustration of the design, he a multiple individual tubes pipe run.</li></ul>

In Figure 1, which is preferably consisting of plastic tube designated RO, in which case the proximal end is illustrated, ie the part in which takes place the introduction of the cable and the supply of the flowing medium. The tube RO is a pressure cap PC pressure-sealed, which is fixed for example by a clamp or bandage BD at the end of the tube RO. About one coming from behind terminal VS in the pressure cap PC the flowing medium SM is supplied, which by a corresponding pressure source PS (see FIG. 3) is supplied.

It can be either a liquid or preferably air.

In the pressure cap PC a number of inlet channels are ECI - ECn incorporated, which run approximately parallel to the longitudinal axis of the tube RO. Each of these inlet channels has a passage opening, as it is significant visible and DO3 at the inlet channel EC3. Normally, each of these inlet channels ECI-ECn is stoppered (at EC3 with ST3 designates) closed, which is held in pressure-tight, for example by an appropriate hose clamp or characterized in that the plug is screwed by a thread. There are a total of as many inlet openings ECI-ECn provided later optical cable to be maximally absorbed. In the present example it is illustrated how an optical cable CA2 is drawn into the inlet duct EC2 this purpose may be one provided (right opposite from the inlet channel EC2 and not shown here) simple pushing device (for example, bead), which exerts a longitudinal force on the optical cable CA2 and in this transported into the interior of the tube RO. The actual further movement, even with curved pipe run is, however, caused by the highly turbulent flowing medium SM which engages the respective optical cable to be recovered, for example, OC2 and this deformed wavy and thereby moved longitudinally. So there is a push process, ie attack of the flowing medium at each wave crest of the cable. The use of pistons or the like at the distal cable end, is unnecessary in this method. Such pulling aids would also bring with it the disadvantage that through them for .B. easily lead to bottlenecks in blocking what. in an easy clean cut, not thickened distal end of the cable as in the invention, is not the case Suffice it at the far end of the cable a simple cap, which prevents impaling or splicing the cable. This Einschießvorgang is not appreciably impeded or influenced by already recovered or injected cables. It is expedient to inject as uniform as possible cable. The cable should also be sufficiently flexible to be deductible from the turbulent flowing medium in waveform and thus moved forward to who-the. A longitudinal tension (eg by a piston at the cable beginning) was to stretch the cable and thereby eliminate the waveform and prevent "gequanteten feed" by attacking the turbulent flow on the wave crests. After the drawing-in, the entry point at the respective inlet channel, eg EC2, also be sealed, whereby the penetration of water is prevented in the cables laid pipe. In this case it is advisable to seal correspondingly the remote pipe end FE to Figure 3 of the pipeline route ROS, for example by a corresponding filling mass of bitumen. During the actual drawing-in contrast, the far end of the pipe FE is open while the nearby pipe end NE is closed by the pressure cap PC.

Overall, after pulling multiple cables CAl CAn and after completion of the drawing-in a structure similar to the illustration of Figure 2. The optical cable CAL CAn lie on the bottom of the tube RO. To improve clarity of presentation that region of the optical cable CAl-CAn is omitted, the arcuate runs respectively from the input channel in question to the illustrated position of the optical cable CAl-CAn.