Patent Publication Number: US-6699324-B1

Title: Method for coating the inside of pipes and coating system

Description:
BACKGROUND OF THE INVENTION 
     The invention concerns a method for coating the inside of pipes and similar longitudinally stretched hollow objects according to the generic terms of claim 1. The invention also concerns a coating system for the coating of the inside of pipes and similar longitudinally stretched hollow objects according to the generic terms of claim 2. 
     The pipe line network for the gas supply as well as water and sewer lines of towns and municipalities usually consist of steel pipes that are welded together. While pipes in newer pipe networks have been given an interior coating of e.g. Polyurethane by the manufacturer to protect against corrosion, older pipes do not feature such an interior protective coating and are therefore subject to corrosion which in the course of their operation can lead to leaks. Often, such pipelines are being replaced by a new pipeline after a long operation period. To lay new pipes however is time consuming and expensive, especially when it requires work in the ground or on streets. For this reason, it is aspired that pipes and similar longitudinally stretched hollow objects can be restored from within by giving the inner surface a suitable coating. If the pipes are sufficiently large enough in diameter, suitable machines with spray devices can be inserted and with their help the inner wall can be coated with the necessary Polyurethane or with another coating. 
     It is also known too first of all test underground pipe lines for eventual damage with a device that rests on the pipe walls. With a post-ceding device the damaged areas are re-coated and repaired. Such a device is known from the U.S. Pat. No. 4,691,728. Similar procedures are known from the PCT WO 96/06298 and PCT WO 96/06299. A process that works on concrete is subject of the DE-OS 14 50 384. In addition, from the DE 196 41 887 A1 a device is known for the thermal coating of the interior of positioned pipes. A motor driven pipe vehicle features a flexible work head at its end which holds a sand blaster jet or a welding torch. The vehicle is driven into the interior of the pipe which first of all will be blasted with the help of the sand blaster jet and then coated with a metal by the means of the welding torch whereas welding material and other coating substances will be added. A coating system that can be driven inside the pipe is described in the DE 198 41 891 A1, where the vehicle features a distributor, which more or less exactly applies the coating to the inner wall. A defined coating of the pipe is therefore not mentioned especially since the vehicle can only be moved towards one direction via a rope. A vehicle pulled by a section of piping is known from the EP-A-O 145 266. The vehicle consists of two parts and runs on fixed, non-adjustable skids, features a camera that precedes the vehicle in the main travel direction and which can only extend the rotor sprayer by a minimal degree against the travel direction to correct eventual mistakes immediately. The section of piping is being rolled onto or off a power driven spool without guidance. 
     SUMMARY OF THE INVENTION 
     The invention has the task to create a method and a coating device with which an interior coating of pipes and similar longitudinally stretched hollow objects can be achieved that can be defined and adapted to the individual conditions of the interior wall of the pipe. 
     The task is solved according to the invention by the characteristics of the typifying parts of claim 1. 
     With such a method, it is first of all possible that a defined inner coating can be applied because the process can continuously be monitored and corrected. The fact that the vehicle is moved through the pipe via the section of piping and exclusively via the section of piping, it is ensure that the section of piping into which the various components are pumped from the storage containers to the deployment location is always tight so that operational disruption through a bend or similar circumstances cannot take place. The vehicle and therefore also the distributor are always positioned in the middle of the pipe or the duct so that it is guaranteed that the mixed components from the distributor or the corresponding material always travel the same distance and settle evenly on the inner wall. The vehicle is being pulled forward via the section of piping, however, with a suitable device it can also be pulled in opposite direction so that flaws detected through monitoring can be corrected immediately, meaning without traveling long distances. Thus, a continuously even coating or securing of the inner wall of the pipe is guaranteed. The section of piping is safe from any bends or other disruptions and can foremost ensure a smooth movement of the vehicle which is additionally supported by the tensile design. The section of piping which carries the different components as well as compressed air and electricity remains undisturbed during the rolling on and off process because the section of piping in the tensile design also has an appropriate stability. Moreover it is intended in addition that the section of piping that moves the vehicle is guided onto and off the spool which also serves as a drive and thus it always remains connected with the coating agent storage containers. This special method ensures that even with a short noticed stop of the distributor or standstill of the vehicle the coating process can immediately continue after the vehicle continues to move. The necessary coating material but of course also the additional components are always readily available. 
     To complete the procedure, a coating system to coat the inside of pipes and similar longitudinally stretched hollow objects is intended which is equipped with a vehicle that is guided along the inner wall of the pipe by a drive and which features a distributor for the coating agent. The vehicle is connected with at least one coating agent storage container via a flexible section of piping whereas the section of piping is connected with a spool positioned outside the pipe whereas according to the invention the spool which serves as a tensile drive via the section of piping and which features a drive and a central, pipe-shaped spool axis whose at least one free end is equipped with a sealed pivotal connector at whose solid part at least one feed line from a coating agent storage container comes in and whose part that is connected with the pivotal part of the spool is connected to one of the product lines in the section of piping which in turn forms the tensile section of piping together with if necessary additional for the operation of the vehicle required supply lines. The section of piping can be rolled off the spool. The vehicle then also features a camera car and a rope on the side where the rotating distributor is located. Thus a coating system has been created which first of all can be pulled in one direction through the pipe or the underground duct evenly and without disruptions via the spool featuring the drive and the section of piping. Since the spool is positioned on the ground, special safety measures which otherwise would have to be considered do not have to be followed. Therefore the drive can be very simple in its design. A direct and constant connection of the vehicle and the distributor with the coating agent storage container is possible via the pivotal connector. The same is true of course with multiple storage containers. The section of piping itself is tensile so that there are no relaxed portions within the piping and thus no irregular operation of the vehicle. On one side the vehicle is connected with the section of piping and on the opposite side with a rope where also a camera cart can be attached which can monitor the coating process continuously and can ensure that when mistakes occur, for example irregular coating or missing sections of coating, the vehicle can immediately be stopped and pulled in the opposite direction in order to correct the mistake immediately while the process is being monitored. 
     In order to ensure an even rolling up and rolling off of the section of piping onto the spool over extended time and with multiple rolling up processes, the invention intends that the drive of the spool and the drive of a pair of preceding pressure rollers feature an electronic control which match the even pulling force one the one hand and the speed to roll up the section of piping on the other hand. Thus, over extended time, the powered spool can be used as the exclusive drive for the vehicle that is to be moved in the duct or in the pipe whereas the preceding pair of pressure rollers ensure the even rolling on and rolling off process as well as the even supply of section of piping. 
     According to further development it is intended that two pairs of pressure rollers are intended which are positioned one after the other towards the pulling motion and of which each features one pressure roller that is powered whereas the other pressure roller follows due the frictional pressure of the coating surface of the section of piping while the drive of the spool is built so that it follows the drive of the pairs of pressure rollers and at least one pair of pressure rollers can be extended parallel to the spool axis preferably on a carriage. Thus the section of piping can be evenly rolled on and off while it is ensured that the section of piping is also evenly moved between the spool and the pairs of pressure rollers while at the same time the rolling up process is facilitated because the pairs of pressure rollers move back and forth in front of the actual spool in such a way that the section of piping can always be rolled on tightly together onto the spool or rolled off the spool. 
     The even distance of the vehicle to the inner wall is ensured by the fact that the vehicle features a casing with six or more in radial direction extended gliding skids whose contact surface can be set towards the longitudinal middle axis of the vehicle. Thus the necessary adaptation to the changing diameter of the pipe can take place while it is thinkable that the gliding skids feature corresponding rollers or other glide media if this is deemed necessary and useful. 
     An even coating of the inner wall of the pipe or duct cannot be ensured by a simple spraying on of the coating material because the rotating distributor can also easily apply coating material onto already applied coats. In order to ensure most optimal coating it is intended that the rotating distributor is designed as a rotation symmetrical pot with outlet openings and that it features a pipe which leads into the inside of the pot and is fixated opposite to the casing of the vehicle and features a beveled open end piece whereas as the slanted opening points outwards to the closest area of the inside wall of the pot. Due to the outlet openings which are differentiated in at least two groups, it is possible to achieve a sufficient thickness of the coating as well on critical parts of the inside of the pipe such as at steps, ledges or inward pointed elevations. In relation to this effect it is especially advantageous when the outlet openings of the first group are tilted forward in relation to the longitudinal axis of the vehicle or the pipe and the outlet openings of the second group are tilted backward in relation to the longitudinal axis of the vehicle or the pipe. In this case, for example with inwards pointed elevations on the inside wall of the pipe the corners of such ledges which are pointed backwards in relation to the direction of the vehicle will be reached by the forwards pointed coating material jet while on the other hand the corners that point forwards in relation to the direction of the vehicle are reach by the coating material jets that face backwards so that overall, even at such critical points, a sufficient coating can be achieved. The outlet openings are preferably mostly cylindrically shaped drillings in the material of the distributor. The drillings allow a coating jet to be exactly defined in terms of its exit angle. The rotation symmetrical pot of the distributor prevents an uncontrolled release of coating material because the diameter of the inner wall at the open end of the pot is less than at the axial portion of the inner wall from where the distribution outlets start. Due to the exact placement of the pipe end inside the pot it is ensured that the transportation of the coating material happens on the shortest distance into all areas in the pot that feature outlet openings. Also, it is prevented that the coating material gets into areas where it could be distributed in an uncontrolled fashion for example at the open rim of the pot. 
     Another useful design intends that the rotating distributor is designed to function as a spray-gun with a radial positioned outlet opening and integrated mixer and that the shaft of the pivotal drive which turns the spray gun features a media through put or is a media through put. Thus is it possible for the first time, specifically, and in terms of the surrounding quasi continuously, to apply the coating agent without running the danger that an application of a coating agent is too thick or that a double application through the jets would cause the coating material to drip or to run. Instead, an exact, predetermined amount of coating material or two component mixture is applied onto the inner wall of the pipe by the spray gun which proceeds with the coating process in a spiral-like motion because the vehicle is moved evenly along the inside of the pipe. Due to the special design it is possible to select the thickness of the coating in such a way that when the connecting point is reached after one full turn of the spray gun the two component mixture is hardened enough that dripping or running is no longer possible. It is especially advantageous, however, that with a spray gun according to the invention the coating process can be disrupted at any time because the mixing of the two components happens inside the spray gun, and to be exact, in the spray head, so that after the appropriate off-time usually the coating (process) can be continued without any problems. This can be achieved for example by the fact that the compressed air that is already transported any way is used to clean the gun so that the completely clean spray gun is ready to continue the coating process. Thus, it is possible for example to plan the coating in sections and thus only in the areas that have damages in order to then move the entire vehicle to the next location and to continue the spraying again. For the first time it is therefore possible without driving back and forth for several meters or to spray more then 100 meters in sections because liners or other similar objects do not have to be used. 
     According to another useful design of the invention it is intended that the media through put is designed as a cylinder casing with a component connector for the two components and the compressed air connector and that the cylinder casing houses the shaft which is connected with the compressed air powered pivotal drive and that the shaft features outer ring channels and axial sack drillings that correspond with the connectors. The two components as well as the compressed air are inserted into the rotating spray gun via the media through put without causing a strain on the section of piping. The two components and the compressed air are transferred gently from the distribution station above ground to the job site inside the pipe to the be induced through the media through put into the spray gun to be mixed there and sprayed on. As it is seen in the characteristics in the claims section, the components can really be transported separately until close to the mixing location upon which they are being transported all the way to the handle of the spray gun. It is an advantage that the compressed air, which is also needed for other purposes that will be explained later, is used to turn the shaft and thus the spray gun. Via the compressed air the rotation speed can be set so intricately that the previously described even application effect can always safely be achieved. 
     The vehicle is moved in the pipe line or the duct via the section of piping which can be rolled up. On the one hand to enable an exact positioning of the vehicle in the pipe and also to take care of corrections, the invention intends that on the free end of the spray gun a flexible rope attachment piece for a rope is positioned that can be pulled in opposite direction. The rope that pulls in the opposite direction gives way enough that the vehicle can be moved in its intended direction but can also be activated in such a way that the vehicle moves backwards in its intended space or in other words is pulled backwards. A strain on the rope is being avoided because a pivotal head is intended between the turning spray gun and the rope pulling in the opposite direction so that the spray gun turns without transferring this motion onto the rope. 
     The portrayed section of piping can serve in a double function due to the fact that it consists of the two separate product lines which can be heated and two partial shells and a middle piece which features channels or partial channels for the product lines and additional support lines. Thus, a sufficiently stable enough layer can be placed around the product lines and the supply lines which for once takes care of the fact that the necessary pulling forces are transferred but that at the same time an isolation of the inner lines takes place which ensures a flawless operation of the coating system. Only when both products are transferred to the job site at the right temperature, a correspondingly fast and safe hardening at the inner wall of the pipe or the duct wall is required and accordingly possible. Accordingly, there are channels for the products lines intended in the lower half shell. The other supply lines are either arranged around the product lines or mostly in the upper half shell so that after integrating the appropriate lines the two partial shells and the middle piece can be inserted into each other and fixated in such a way that an even operation of the entire coating system is guaranteed. To connect the two partial shells that can be integrated and that enclose the middle piece, it is intended that the two partial shells are connected via a groove-spring connection, the middle piece and the product and supply lines fixated and connected with each other. The groove-spring connection can easily be complemented for which usually glue or other similar materials are inserted into the groove, so that the insertion of the spring enables a simple and safe connection. It is also thinkable that groove and spring are designed to correspond with each other so that by putting (them) together a first fixation is achieved. 
     An additional design of the invention intends that the rotating distributor features a radial positioned and executing outlet opening which corresponds with an atomizer air spray jet which is fitted with an airflow change nut that influences the spray angle of the media output. Via such a designed rotating distributor it is possible due to the corresponding air spray jet to wrap a layer of air around the individual coating jet which therefore guides the two component mixture exactly onto the inner wall of the pipe that is to be restored. Due to the air layer the over-spray of the two component mixture is also made more difficult. Depending on the shape of the air ring channel around the coating jet it can be worked exactly so that the air channel is widened just prior to the jet hitting the wall so that material over-sprays can be prevented. It is advantageous that via the air jet change nut the spray angle can always be changed and thus to accommodate the given situation. If for example the distance between the outlet opening and the pipe wall is small it usually is advantageous when a large spray angle is used while with larger distances the spray angle gets smaller or is small in order to guide the media jet exactly onto the inner wall of the pipe. Thus, it is thinkable that the air pressure change nut is either remotely set or set prior to putting the system underground in order to select a most exact definition of the media jet in connection with the air distribution jet. 
     Additionally it is intended that the rotating distributor consists of a supporting pipe with interior mixer which is connected with the spray head of the spray gun, an angled pipe with the outlet opening and the air pressure regulating nut whereas in the end piece of the angled pipe which points towards the inner wall there is an additional mixer reaching all the way into the outlet opening and whereas the atomizer air jet is detachably connected with the angled pipe and consists of two jet parts which are connected via a thread and of which the jet part that is positioned at the free end is designed as the air regulating nut. The design is therefore appropriately simple and thus can be manufactured cost effectively enough that it can be exchanged if necessary. According another useful design which is detailed in a later part of this documentation it is possible to blow out the distributor in order to, even with slightly longer breaks, prevent the caking of the two component mixture inside the distributor or inside the supporting pipe and the air jet. The previously described simple design of the rotating distributor still facilitates a long mixing process for the two components so that with exiting the outlet opening the necessary requirements for a fast adhesion and setting of the two component mixture are in any case fulfilled. After the re-routing of the previously mixed or pre-mixed two component mixture the material is then pushed through the second mixer and is handled intensively enough that the previously described optimized amalgamation is given when exiting out of the exit jet. An exchange of the air jet at the end of the supporting pipe and the angled pipe is possible because the air jet is detachably connected with the angled pipe and consists of two jet parts which are connected via a thread of which the jet part which is positioned at the free end is designed as the air regulating nut. With that the regulation of the coating jet is easily possible because only the air pressure regulating nut, thus the jet part which is positioned at the free end, has to be turned on the thread in order to regulate the angle of the jet to correspond with the situation. 
     The compressed air that is necessary to form the air in layer is added in the shortest possible way and that is because that the jet part that is connected with the angled pipe features an air connector and an air distribution chamber which is connected via axial air channels with a second air distribution chamber in the air pressure regulating nut, whereas a connector for compressed air is intended in the area of the spray head which via a pivotal connector ensures a continuous supply of air and which can be connected between the supporting pipe or the mixer and the medium valves. Due to the positioning of the air chambers it is ensured that with exiting from the exit ring channel an even air layer is being formed so that outbursts of the two component mixture can be prevented. For that, the second air chamber in the air pressure regulating nut is especially important, whereas it is shaped like a half dome and in such a way that the lowest point points toward the exit ring channel so that compressed air is being released in this area and thus exits appropriately. Thus, the compressed air can specifically enter in this area and can exit appropriately. An especially specified and even air layer is put around the coating jet. Thus, it is also thinkable to change the thickness of the wall of the exit ring channel, however, for this the air pressure regulating bolt would have to be equipped with a special feature. Usually, it is sufficient if the once set or pre-determined exit ring channel ensures that a sufficiently thick air coat is created whereas of course the exit speed of the compressed air from the exit ring channel has also to be taken into consideration. The rotating distributor is blown out at or shortly prior to standstill in order to use it again without any problems. Through the rotating connector it is ensured that the compressed air flows continuously and not only when the rotating drive has come to a standstill. This has the advantage—as further explained later in the text—that the connector for the compressed air can also simultaneously be used for the supply of the air jet. 
     The section of piping can advantageously be used for the supply and for the drive of the vehicle by integrating product lines and electrical supply lines in a highly resistant flexible tube thus building the section of piping. At the end facing the vehicle the section of piping is air tightly sealed by a cover or facing the tube spool side it is air-tightly sealed by a cover featuring a terminal block and at the same time it is configured to absorb tensile forces. The product lines which transport the two components of the coating material point towards each other in the outlet opening preceding the mixer which also features a compressed air supply line with an air jet that connects in a right angle to it. Such a designed section of piping makes it possible to pull the required product lines, supply lines and other cable or other similar items into the highly resistant flexible tube and to store them therein. In the event that the 150 m long or longer section of piping shall be used to pull the vehicle through the duct or the pipe, the section of piping or better the highly resistant flexible tube is filled with compressed air and inflated to the extend that the highly resistant wall effectively protects the product lines and supply lines within and also ensures the necessary isolation. Through the air that is built up in the highly resistant tube the product lines are kept at temperature as much as necessary because the air can act as an isolator and thus be supported by the wall of the tube. In addition, tensile forces can be applied without running the danger that the product lines or supply lines can be overly strained and effected by the tensile forces in any way. It is also advantageous that weight can be reduced by omitting a section of piping that fully consists of material. It is especially advantageous that the manufacturing of such a protective coating for the product lines, electrical supply lines and other lines is expressively simple because only a highly resistant tube is necessary which doesn&#39;t require any preparation procedures. It is only fixated through covers at the ends and/or terminal blocks and equipped in such a way that it can on the one hand be connected with the vehicle and on the other hand connected with the roll up device. The coating material is being pumped through the product lines to the vehicle and is mixed here in such a way that the two components are applied at the same time to the inner wall of the pipe or duct. It is followed by a pressure mix with injector effect because the compressed air which is induced at the same time, therefore the mixed or pre-mixed coating material is pressed and pushed into the outlet opening and thus into the jet so that the coating material is thrown onto or sprayed onto the inner wall as a complete mixture. It has been found that with the described design the mixing of both components can happen on short distances and fast so that correspondingly smaller built devices can be used. The individual component material that exits from opposite from each other positioned openings of the product lines is swept away by the air stream and is skillfully mixed and increased in speed so that it can even be applied to pipes featuring larger diameters without bouncing off the inner wall. To fulfill this purpose, the product lines transport the coating material under appropriate pressure. For example, the component material which is required in large quantities is pushed through the section of piping with 100 bar whereas the component material that is required in a lesser quantity is transfer with 50 bar to be joint at the mixer. By changing the pressure the quantity can thus be changed and adapted to meet the individual requirements whereas depending on the applicable situation and the coating material that is to be used the quantity of the component is predetermined and thus also the pressure conditions relating to the two product lines. 
     Previously in the text it has been indicated that the highly resistant flexible tube is sealed by covers at the ends and that it is also configured to absorb tensile forces. At the same time the necessary also tensile connection between this part and the highly resistant tube is ensured by the fact that the cover or the terminal block is connected with a tube spout which is positioned far into the tube and held by an outer teethed link and which is equipped with corresponding ring grooves to hold an O-ring. The tube spouts with their outer teethed links are inserted into the tube prior to it being pressurized. Thus, a positioning is possible, whereas it is practically impossible to pull out the tube spout due to the outer teethed link and this effect can be increased if necessary by tube clamps. With the appropriate fixation of the tube spouts in the highly resistant tube, the opportunity is created to tightly attach those tube spouts at the cover or the terminal block especially to screw them in. The necessary sealing effect in the area of the cover and the terminal block is created by the O-rings. Thus the area between cover and tube spout is effectively sealed so that the compressed air cannot unintentionally escape. Moreover, the compressed tube or better the tube that is filled with compressed air remains in its secured position so that the other contained supply lines are undisturbed and protected. 
     The tube which is sealed on both ends by the covers or the terminal block is to be inflated when in operation in order to ensure the appropriate safety of the product lines, compressed air line and supply lines and to perfectly absorb the tensile forces. For this the invention intends additionally that the cover on the side of the tube spool features a connector drilling for a low pressure line to add compressed air, preferably ranging from 2 to 4 bar and that the drilling features a sealing coating that works together with the outer wall of the product lines, compressed air line and supply line. With this low pressure line, compressed air is guided into the inside of the tube so that it can inflate due to the fact that it is closed and sealed on both ends with the covers so that therefore it obtains the necessary stiffness or that its stiffness is ensured. The coating can of course also be assigned to the individual supply lines and other lines, however, it is really only necessary in the area of the insertion in the area of the drilling so that it is more useful to equip the inner wall appropriately. The appropriate coating has the additional advantage that an even insertion or pulling through motion of the supply and other lines is facilitated. 
     The section of piping that is being used or the appropriate tube has a total length of 150 meters or more, and it is rolled up on an appropriate tube spool or is rolled off of it depending on which the direction the vehicle moves towards. On the one hand to absorb tensile forces that develop and on the other hand to optimize the flexibility of the tube in the best way it is intended that the wall or the highly resistant tube features a reinforcement whereas this reinforcement does not necessarily have to be designed in a spiral shape but can also consist of rings that are either set on the outside of the tube or are integrated in the tube or are positioned on the inside in order to ensure the appropriate stability. The spiral shaped design as well as the ring shaped design ensures that the tube can be rolled up in any case. 
     The invention distinguishes itself especially by the fact that a method for the interior coating of pipes and similar longitudinally stretched hollow objects has been designed and that in addition a coating system with which the application of the coating material is enabled continuously and in such a fashion that the coating procedures in sections of 150 metes or more have an even and flawless result. The vehicle is pulled evenly through the pipe or duct that is to be coated by the powered section of piping which can absorb the tensile forces and which is to be pulled evenly through the duct or the pipe by the especially designed spool. Loops or entanglements are not possible so that an even supply of the vehicle and the distributor is ensured. The section of piping is simple in design and can be inflated so that the interior product lines and supply lines are very safe and that at the same time it is possible to keep the temperature (warm) so that the coating components can be transferred safely to the distributor even over great distances. The vehicle is always guided in the center of the pipe, can be moved in both directions and allows an immediate supervision of the coating effort so that mistakes can be corrected very quickly and on the shortest distance possible. 
     Additional details and advantages of the invented object can be found in the following description of the corresponding drawings where a preferred design example is depicted with the necessary details and individual parts. It is shown in: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 a coating system to coat the inside of pipes in an extremely simplified drawing, 
     FIG. 2 a vehicle that can be moved inside a pipe, 
     FIG. 3 a distributor in a sectional diagram, 
     FIG. 4 an interior view of the distributor, 
     FIG. 5 a front view onto the vehicle, 
     FIG. 6 a sectional diagram through a section of piping, 
     FIG. 7 a side view of the spool onto which the section of piping is rolled onto, 
     FIG. 8 a view onto the spool from above, 
     FIG. 9 a back view onto the spool, 
     FIG. 10 a side view of the vehicle, partially in a section 
     FIG. 11 a sectional diagram through the section of piping, 
     FIG. 12 an explosion drawing according to FIG. 11 
     FIG. 13 a distributor with air jet 
     FIG. 14 a coating system with camera car in side view 
     FIG. 15 a section of a rotating distributor, 
     FIG. 16 a section of piping with inflatable tube. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBIDIMENT 
     The essential elements of the coating system are explained at first with the overview diagram of FIG. 1. A to be restored pipe  1  is located in the ground and for the restoration process it is divided into individual pipe sections. The pipe sections are separated from each other by pits  2 . Therefore the to be restored pipe section is located between two consecutive pits  2 . 
     The restoration of the pipe takes place by coating its interior lining. For this, a vehicle  3  is moved through the pipe  1  by pulling it through the individual pipe section by a section of piping  4  that withstands tensile forces and is wear and tear resistant and equipped with supply lines for the vehicle  3 . Thus the vehicle  3  travels from pit  2   a  to pit  2   b  where the vehicle exits from the pipe  1 . Guiding rollers  5  are used to gently guide the section of piping  4  which is finally rolled onto a spool  7  that is mounted on a service vehicle  6 . 
     The service vehicle  6 , e.g. a truck, holds in addition to the spool  7  various supply containers, e.g. two coating agent storage containers of which only one container is depicted on FIG. 1 in order to simplify the overview. The coating agent storage containers contain products that are transported to the vehicle  3  via the section of piping  4  that also serves as a flexible pull element so that they can process the inner coating of the pipe  1  at its location. 
     In order to pull the section of piping  4  to the end of the pipe  1  at the pit  2   a  prior to the coating procedure, the section of piping  4  can temporarily be linked with a rope  9  which is connected with a motorized winch on its other end. By operating the winch  10 , the section of piping  4  with its containing supply lines can be pulled by the rope  9  to the individual end of the pipe. Then the rope  9  will be detached for which corresponding coupling elements  43  on the section of piping  4  and on the rope  9  are intended. Then the vehicle  3  will be connected with the section of piping  4  upon which the coating process can be initiated by pulling the section of piping  4  in an exactly controlled manner. 
     Instead of a direct connection between the section of piping  4  and the rope  9  via the coupling elements on both sides it is also possible to pull the vehicle  3  with the rope in to pipe  1  almost all the way to the pit  2   a  while it is already connected with the section of piping  4 . This case is depicted in FIG.  1 . 
     With FIG. 2, the following details of the vehicle  3  are explained while it is pulled along the inner wall of the pipe. It consists of a casing with six or more skids  11  that extend in radial direction The skids are positioned in equal angles to each other. Via elongated holes  12  and corresponding screws the skids can be move in a radial direction so that the radial distance of the surface  13  of the skids  11  to the longitudinal axis  14  of the vehicle  3  can be set. This can be seen especially well on FIG.  5 . Thus, the effective diameter of the vehicle  3  can be adjusted to fit the individual interior diameter of the pipe. In addition, the skids can be exchanged so that skids with larger radial extensions can be used for larger pipe diameters. The skids feature bevels  15  at both of their ends so that it is ensure that they can glide along the interior wall of the pipe without a problem. Each skid  1  is mounted on springs  16  to allow a certain compensation towards irregularities of the inner wall of the pipe. The length of the skids  1  is at least two thirds longer than the diameter of the pipe  1 . For example, if the pipe measures 300 mm in diameter, the length of the skid is at least 500 mm. 
     An important element of the vehicle  3  is the distributor  18  which is located at one end of the vehicle on centrally positioned drive shaft  17  in the shape of a pot that opens towards the vehicle. The drive shaft  17  is centrally positioned, therefore matching the longitudinal axis  14  of the vehicle  3  and is powered by an air compressor  19  with at least 15,000 to 17,000 revs per minute and up to 30,000 revs per minute. The air supply of the air compressor  19  takes place via the compressed air line  20  which is part of the section of piping  4 . 
     In addition to the compressed air line there are another two product lines  21 ,  22  that lead into the vehicle  3 . The product lines  21 ,  22  are also part of the flexible section of piping  4 . The product lines  21 ,  22  lead to the preferably heated mixer  23  inside the vehicle casing. Here, the two products are mixed to become the desired coating agent. This (mixture) reaches the inside of the pot-shaped distributor  18  via a rigid pipe  24 . 
     As it is visible in FIG. 3, the pipe  24  is located in an offset position to the central drive shaft  17  and features a beveled opening on its free end between 30 and 40 degrees through which the coating material can exit. The beveled edge  25  points outwards to the closest area of the inner wall  26  of the pot as can be seen in FIG.  3 . 
     With the vehicle  3  it is possible to preferably apply a polyurethane coating to the interior wall of the pipe. For this, one product line  21  carries for example Polyol and the other product line carries for example Isozyanat to the heated mixer  23 . 
     Details of the pot-shaped distributor are explained as follows with FIGS. 3 and 4. Besides the drive shaft  17  which is made of steel the entire distributor  18  is made of plastic or aluminum. Due to the shape of the pot it is outwardly closed and features an opening  27  towards the vehicle  3 , which, like the entire distributor  18 , is rotation symmetrical in relation to the longitudinal axis  14 . This prevents imbalances in view of the high number of revolutions. 
     The inner wall  26  of the pot is conically shaped towards its front wall  28 . The inner wall towards the vehicle, on FIG. 3 on the left, is shaped as a cone  28  which however becomes narrower towards the opening  27 . The diameter of the inner wall  26  is therefore less at the open end of the pot than at the axial section of the inner wall from where the outlet openings  29 ,  30 ,  31  are positioned. The outlet openings  29 ,  30 ,  31  extend from a common circle  32  which is defined on the inner wall  26  of the pot. For better display purposes, the circle  32  is sketched with short lines. 
     The outlet openings  29 ,  30 ,  31  are basically cylindrical drillings in the plastic material of the distributor  18 . The outlet openings  29 ,  30 ,  31  are divided into three groups: 
     The first group of outlet openings  29  points forward in relation to the longitudinal axis  14  resulting in the coating jet  29   a . A second group of outlet openings  30  points backwards in relation to the longitudinal axis  14  resulting in a coating jet  30   a . A third group of outlet openings  31  are set in an exactly radial position to set a coating jet  31   a  in a right angle to the longitudinal axis  14 . 
     FIG. 4 shows that by looking at a sectional diagram of the pot, the outlet openings  29 ,  30 ,  31  can have different exit angles. While one outlet opening extends radial and results in a radial coating jet ee, other outlet openings are tangent so that in each case it results in a tangent coating jet  34 . 
     All outlet openings  29 ,  30 ,  31  are evenly distributed over the circumference of the pot whereas the relation between the number of the outlet openings  29 ,  30 ,  31  is 1:1:2. 
     Through the different angles of the three outlet openings  29 ,  30 ,  31  three circles are defined that are off-set in axial positions to each other on the outer circumference of the distributor, in FIG. 3 indicated with the corresponding numbers  35 ,  36  and  37 , and which indicate the axial locations of the mouths of the outlet openings  29  or  30  or  31 . 
     While the vehicle is in operation, the coating material comes through the pipe  24  which is fixated in the casing of the vehicle until it reaches the beveled edge  25  and from there hits the inner wall  26  of the pot which rotates at a high revolution. Thus, the material is distributed evenly onto the inner pot circumference and due to the high centrifugal forces exits through the outlet openings  29 ,  30 ,  31  so that the coating material is flung onto the inner wall of the surrounding pipe and sticks there. 
     FIG. 6 shows a sectional diagram through the section of piping  4  with the product line  21  for Polyol, the product line for Isozyanat and the compressed air line  20 . The two product lines  21 ,  22  together are the supply line that leads to the mixer  23 . Both product lines  21 ,  22  are equipped individually with their own heating system. This consists of a interior Teflon tube and a metal mesh  38  that surrounds it and which carries electricity and an outer protecting tube that in turn is directly imbedded in a vulcanized rubber coating of the section of piping  4 . 
     The heating of the supply line takes place in sections for which a corresponding number of inlets  40  are imbedded into the rubber coating  39 . In addition, sensor lines  41  are imbedded to control an exact, pre-determined temperature of the individual sections. 
     The rubber coating  39  of the section of piping  4  consist of a relative resistant tensile material so that the tensile forces that are necessary to move the vehicle through the pipe can be applied without causing damage to the individual lines inside the section of piping. 
     FIGS. 7 through 14 relate to the rolling up of the section of piping  4  onto the previously described spool. The necessary tensile forces for the pulling of the section of piping  4  however are not a result of the drive of the spool  7  but come from a separate drive which consists of pairs of rollers  42 . In the overview drawing according to FIG. 1, there is only one pair of rollers  42  depicted whereas in the designs according to FIGS. 7 through 9 there are altogether two pairs of rollers  42  present. Each pair of rollers  42  consist of a powered pressure roller  44  and an additional pressure roller  45  which is operated due to the friction connection with the surface of the section of piping  4 . The two pressure rollers  44  can be operated via a common drive  46  via appropriate belts, as can be seen in FIG.  7 . 
     The spool  7  is also equipped with a drive  47 , preferably also with a belt  48 . An appropriate, electric control ensures that the roll up speed of the drive  47  operates with the same speed than with which the pair of rollers transport the section of piping  4 . In order to operate the speed control in very small increments the pulling of the section of piping  4  however takes place exclusively via the pairs of rollers  42  which allow for a very precise speed control with high tensile forces due to their small diameters. The drive  47  of the spool  7  therefore only operates as a lagging drive. 
     FIG. 8 shows that the individual windings of the section of piping  4  are rolled up so that they are located next to each other on the spool  7 . In order to avoid an overlay of the individual windings, the pair of rollers  42  are located on a carriage  50  that can be moved in parallel direction to the axis of the spool  49 . The movement of the carriage  50  parallel to the axis of the spool  49  is coordinated with the transport speed of the pressure rollers  44  which means the carriage operates with such a speed that the individual windings of the section of piping  4  come to rest exactly next to each other on the circumference of the spool  7 . For this, the drive of the carriage  50  is coupled with the drive of the pressure rollers  44  via a gear system  51 . 
     The powered pressure rollers  44  as well as the non-powered pressure rollers  45  can be equipped with a runner coating to increase the friction so that a higher friction and thus higher tensile forces can be applied onto the section of piping  4 . 
     Because the section of piping  4  and the lines and supply lines within end inevitably at the spool  7 , pivotal inserts are required at this point. FIG. 9 shows that the spool axis  49  is equipped on both ends with sealed pivotal connections  52 ,  53  which extend from the spool axis. At the fixated part of the pivotal connections there are connectors attached whereas the connectors  54  lead to the coating material supply containers  8 . A double line is connected with the pivotal part of the pivotal connector  52  which first leads along the spool axis  49  and then extends into the product line  21  or the other product line  22  of the section of piping  4 . 
     The addition of compressed air for the air compressor takes place via a corresponding pivotal connector  53 . Finally, pivotal contacts  55  are intended via which electricity runs to the heated sections as well as with which the electric sensor lines are checked. 
     FIG. 10 shows a pipe  1  in a cross section in which a vehicle  3  can be moved evenly. For this, only the indicated section of piping  4  is used which also serves to bring the required media or components. Not shown is a roller that changes the direction which leads through the pipe  1  to a vertical channel in order to be rerouted above ground or to the area of the street where a service vehicle is located which is also not depicted and on whose spool the section of piping  4  is rolled onto. 
     The vehicle features a number of gliders  11 ,  93  preferably six of such gliders which are pushed onto the interior wall via telescope fixtures  94  that hold the gliders. The telescope fixtures  94  that hold the gliders which feature springs that are not depicted, is positioned via pressure rollers  95  which can be moved via pneumatic cylinders in such a way that they push the gliders  11 ,  93  either against the inner wall  58  or that they enable a retraction of the telescope fixtures  94  that hold the gliders. 
     Number  18  identifies a distributor which is here designed as a spray gun  60  which is continuously turned on the shaft  61  via a pivotal drive  62 . The pivotal drive  62  is equipped with an air compressor  19  which is supplied with the necessary energy via the compressed air line which will be explained in greater detail at a later point. The compressed air line is identified with  20  whereas the product lines that carry the components are identified with  21  and  22 . The mixer which here features a special shape, is identified with  23 ′ whereas it is located in the head piece of the spray gun  60 . The outlet opening is identified with  29  where the coating jet  30  exits and is guided evenly onto the inner wall of the pipe. 
     The entire vehicle  3  is moved on the gliders  11 ,  93  via a drive usually in the shape of the appropriate spool which is not depicted. During the procedure both components and the compressed air are guided into the vehicle  3  via the section of piping  4  where they will be inserted into the pivotal part via the media through put as shown in FIG.  1  and in FIG.  4 . For this, the media through put  64  features a lengthwise extended cylinder casing  65  with the component connectors  66  and  67  as well as the compressed air connector  68 . The compressed air connector  68  is connected with the compressed air powered pivotal drive whereas it is here indicated in the form of the air compressor  19 . At any rate, this air powered pivotal drive ensures that the shaft  61  turns evenly and that it moves the spray gun  60  so that the coating jet  30  gradually covers the wall of the pipe. At the same time, the compressed air flows via the outer ring channel  70  and the axial drilling  71  all the way to the air gun  60  but also to other parts that are regulated or controlled-by compressed air. The two component connectors  66 ,  67  are connected with the outer ring channels  72  and  74  and guide the individual component via the axial drill hole  73  or  75  to the spray gun  60  where the mixing of the two components takes place in the mixer  23 ′. 
     The individual outer ring channels  70 ,  72 ,  74  are sealed against each other via the sealing rings  7  which are tightly positioned on the inner wall  78  of the cylinder casing  65  in the individual ring groove  76 . The inner wall of the pipe  89  meaning the inner wall of the inner cylinder casing part  65  is made smooth enough so that an effective seal via the sealing rings  77  is ensured. 
     In the area of the final radial wall  79 , buffer chambers  80 ,  81  are design on both sides. Those buffer in chambers can be intended to reduce the weight of the entire device, but they can also be connected with the air compressor meaning the compressed air connector  68  in such a way that this area is continuously pressurized so that at the same time it is ensured that the components or other parts cannot get into the way of the turning shaft  61 .  63  indicates by the way the ball bearing which is to ensure an even turning of the shaft  61  in the cylinder casing  65 . 
     The cylinder casing  65  consists of two flange pipes  82 ,  82 ′ whose flanges  83 ,  83 ′ are used to effectively link both parts. An appropriate screw fixing is indicated whereas the outer flange pipe  82 ′ features a flange  82 ′ on both sides whereas the inner flange pipe  82  features a flange  82  on only one side. On the opposite side a special flange  83 ″ is utilized to connect both parts with each other. Appropriate details are shown on FIG.  10 . Here, it is also visible that the outsides  84  of the sealing rings  77  close off a chamber  85  or  86  which are connected with the outer atmosphere via exchange drillings  87 ,  88 . Should component material get into those chambers  85  or  86  due to sealing rings  77  that are no longer tight, it can be released through the exchange drilling  87 ,  88 . 
     The shaft is turned by the pivotal drive  62  or the air powered pivotal drive  69  whereas a rope connector  93  for the rope pulling into the opposite direction  92  is attached to the free end  90  of the spray gun  60 . This rope connector  91  is shaped as a pivotal head which prevents the rope that is pulling into the opposite direction  92  from twisting. Through this rope that is pulling into the opposite direction  92  first of all an even movement of the vehicle  3  is possible as well a correction if the spray gun  60  does not sit in the exact correct spray position. Due to the rope pulling into the opposite direction  92  the entire vehicle  3  can be moved backwards into the appropriate, correct position. 
     The telescope fixtures  94  that hold the gliders are designed to extend and retract. The pressure rollers  95  are put into either a horizontal brace position or in a release position via the pneumatic cylinders  96  so that a fixation of the vehicle  3  at the inner wall  58  of the pipe  1  is possible as well as a correction if the shaft  61  or the spray gun  60  is not exactly in the predetermined position which is necessary to ensure an even spraying of the two components onto the inner wall  58 . 
     The FIGS. 11 and 13 show a section of piping  4  in a sectional drawing. The section of piping  4  consists of the two partial shells  98  and  100  which are connected with each other via a groove-spring-connection  108 ,  109  enclosing a middle piece  99 . In the partial shells  98  and  100  as well as in the middle piece  99  there are channels  101 ,  102  or partial channels  103 ,  104 ,  105  where the product line  21 ,  22  as well as the compressed air line  20  can be placed as well as additional supply lines  106 . By choosing an appropriate material it is thus possible to apply the necessary tensile forces via the section of piping  4  as well as proved the appropriate isolation that is necessary to create the product lines  21 ,  22  in such a way that he two components can be carried all the way to the spray gun  60  keeping the appropriate temperature. 
     The set up is facilitated by the special design according to FIG.  11  and FIG. 12 whereas the two partial shells  98 ,  100  can be pushed into each other after the insertion of the product line  21 ,  22  together with the compressed air line  20  as well as additional supply lines  106  for which they feature the groove-spring-connection  108 ,  109 . This groove-spring-connection can be designed so that based on its shape a first connection of joints takes place which for example can be permanently connected by inserting a glue or a plastic compound material. 
     In FIG. 13 a coating system is depicted which is intended for the restoration of a pipe  1  here in the shape of a duct. To coat the inner wall  58  of the pipe  1 , a distributor  18  is intended which forms the end piece of the spray gun  60 . This spray gun  60  or the distributor  18  is rotated via a rotary drive  62  so that the coating jet  30  which exits the outlet opening  29  always can be applied to the inner wall  58  in an axial direction. A mixer  23  is located inside the distributor  18  to mix the two components of the two component mixture sufficiently enough that they can be applied onto the inner wall in form of a quick hardening resin or Polyurethane. The supply is controlled by the media valves  115 ,  116 ,  113  indicates the spray head of the spray gun  60 . 
     The distributor  18  first of all features a support pipe  17  which contains the mixer  23  and which corresponds with the spray head. When leaving the mixer  23 , the two component mixture is guided through the angled pipe  118  with its specially stream supporting inner walls  119  into the area of the second mixer  120 . The second mixer  120  ensures that the two component mixture exits from the outlet opening  29  in the area of the atomizer air jet  110  in a optimal composition or better in the optimal mixture due to the second mixing process. 
     The atomizer air jet  110  is equipped with an air adjustment nut  112  with a correspondingly adjusting media exit  111 . 
     In the event of disturbances or shortly prior to turning off the distributor  18  compressed air can be lead into the distributor  18  via the connector  114  and thus into the supporting pipe  117  and the angled pipe  118  so that the remains of the two component mixture are pushed out and to thus prepare the distributor  18  for the next job. 
     The atomizer air jet  110  consists of a jet part  122  which is fixated with the angled pipe  118  and the moveable or pivotal jet part  123 . For this, both jet parts  122 ,  123  feature a thread  124 . 
     The required compressed air is added through the air connector  125  and first reaches the air distribution chamber  126  in the jet part  122  and then gets to the air distribution chamber  129  via the air channels  127 ,  128 . This air distribution chamber  129  itself is shaped like a half dome so that the compressed air can exactly hit the area of the exit ring channel  130 . The exit ring channel  130  ensures that the compressed air wraps around the coating jet  3  in form of an air layer and ensures that it forms an exit angle that is best suited for the inner wall  58 . A useful positioning of the air connector  125  is the air connector  125 ′ which is linked with the connector  114  by the connecting line  132 . The connecting line  132  is accordingly integrated in the supporting pipe  117  and the angled pipe  118 . 
     The exiting air supply stream  133  forms as indicated a type of protecting and guiding layer around the coating jet stream  30 . 
     FIG. 14 shows a pipe  1  in a longitudinal section that is to be restored whereas a vehicle  3  can be seen that can move into the longitudinal direction of the pile  1 . This vehicle  3  is pulled via the section of piping  4  in longitudinal direction whereas the only indicated guiding gliders  11  ensure that it also is kept in the same central position. A rotating distributor  18  with a preceding mixer  23  is located in the front of the vehicle  3 . It (the mixer) features an outlet opening  29  pointing towards the inner wall  58  of the pipe  1 . The rotating distributor  18  is depicted in enlarged format in FIG. 15 where it is powered by a pivotal drive  62  and in the shape of a spray gun  60  is equipped with a mixer  23 . Depicted is a so called Kennex mixer, whereas other kinds of rotating distributors  18  can also be used. On the end, an outlet opening  29  can be seen with an appropriate jet. 
     Not shown in detail is the fact that the section of piping  4  holds a compressed air line  20  as well product lines  21 ,  22  and in addition also electrical supply lines  136  as well as a low pressure line  137  if necessary whereas the latter will be further discussed at a later point. 
     The different media which are carried by the section of piping  4  are guided through a media through put  64  of a special design into the area of the spray gun  60 . 
     With the rotating distributor  18  and the outlet opening  29 , the coating material  135  is evenly applied onto the inner wall  58  of the pipe  1 . Corresponding facts can be gathered from FIG.  14 . Outside of the rotating distributor  135  there is the ‘new’ wall which is identified with  135 . It ensures that the pipe  1  or the corresponding duct can fulfill its full function for a long time to come after the completion of the restoration process. 
     In the design according to FIG. 14, a camera car can be seen with a lens  143  that extends towards the rotating distributor  18 . This camera car  142  is connected with the rotating distributor  18  via a pivotal frame  140  so that it can turn together with the distributor  18 . The outlet opening  29  can therefore apply coating material  135  onto the inner wall  58  without being hindered by the pivotal frame  140 . A corresponding connector  141  which ensures the turning motion features a quasi connection with the pivotal drive  62 . The camera car  142  itself is attached onto the pivotal frame  140  by a pivotal eyelet  145  so that the pivotal frame  140  can turn without influencing the position of the camera car  142 . A rope  144  is attached at the opposite end of the camera car  142  so that the camera car  142  and therefore the entire coating system also can be pulled back into the restored area of the pipe  1 . Thus, a reworking of the wall is indeed possible if this is deemed necessary for whatever reason. 
     The section of piping  4  features a tube  138  which makes up the outer wall, whereas appropriate details can be seen on FIG.  16 . Here, the entire section of piping  4  is depicted which can reach a length of 150 meters and more. The wall  139  of the tube  138  is designed so that it can absorb the necessary tensile forces but also that on the other hand an inflation between the cover  148  on the side of the vehicle and the cover  149  on the side of the tube spool is possible. The cover  149  on the side of the tube spool is supported by the terminal block  150  so that an effective fixation with the tube spool, which is not depicted here, is possible. 
     FIG. 16 also shows the front part of the rotating distributor  18 . The compressed air line  20  as well as the product lines  21 ,  22  lead into the front head, which means into the mixer  23 , whereas the two product lines  21 ,  22  come in exactly opposite from each other. The mixer has a ball shaped mixing chamber  153  into which the individual connecting spouts  154 ,  155  or the compressed air line  20  lead into. Opposite of the compressed air line  20  a jet line  56  leads to the outlet opening  29  with an appropriate jet which is not further discussed here, so that the components which enter through the connecting spouts  154 ,  155  are mixed intensively in the ball shaped mixing chamber  153  and then are whisked away by the air stream that exits from the air jet  152  and are applied through the outlet opening  29 . The materials that have been extensively mixed with each other are then applied onto the inner wall  58  by an appropriate beam depending on the jet. 
     The tube that is identified by  138  is connected with the cover  148  on the side of the vehicle and the cover  149  on the side of the tube spool featuring a terminal block  150  via tube spouts  157 ,  158  whereas these tube spouts  157 ,  158  with their outer teeth are pushed appropriately far into the tube  138 . The shape of the outer teeth  159  is especially shown on FIG. 8 where it is visible that after the insertion of the appropriate tube spout  157 ,  158  into the tube  138  it is practically impossible to pull it back out especially when the tube  138  is inflated. Not depicted are tube clamps which also prevent the involuntary back or outwards movement of the tube  138 . 
     The tube spouts  157 ,  158  feature connecting screws  170  with which they can be connected on the one hand with the terminal block or with the appropriate covers  148 ,  149 . An O-ring  162  is positioned between the terminal block  150  and the cover  148  on the side of the vehicle whereas both parts feature a ring groove  160 ,  161 . In its mounted position, the O-ring  162  is set tightly so that compressed air cannot exit at this point. 
     The individual covers  148 ,  149  feature drillings  163 ,  164  to take in product lines  21 ,  22  or the compressed air line  20  or other lines  136 ,  137 . Thus, the appropriate lines are bundled or inserted into the tube  138  in an orderly fashion so that it cannot lead to overlapping or twisting when the tube  138  is inflated and filled with compressed air. For this, a low pressure line  137  is intended which as can be seen reaches into the area of the tube  138 . Compressed air is inserted via the low pressure line  137  so that the tube  138  inflates and so that an appropriate security and insulation of the lines  20 ,  21 ,  22 ,  136 ,  137  is ensured. The fact that the corresponding lines are equally positioned in both covers  148 ,  149  a clear positioning of the lines inside the tube  138  even with lengths of 150 meters and more is given. 
     The low pressure line  137  leads through the connecting drill hole  165  whereas the connecting drill how  165  as well as the drill holes  163 ,  164  feature a coating material which corresponds with the outer wall  166  of the lines  21 ,  22 ,  20 ,  136 . Thus an effective seal is ensured also in this area and an advantageous predetermination of the individual lines is ensured. 
     The tube  138  can feature a reinforcement  168  in order to establish an additional strengthening of the tube  138 . The reinforcement  168  does not hinder the tube  138  to be rolled up. The reinforcement  168  can be positioned on the outer coat, on the inner wall or inside the wall  139  of the tube  138 . It can have a ring shape or spiral shape. 
     The low pressure line is identified with  137  but also with  169  in order to show that pressure of 2 to 4 bar can be applied but it can also operate with higher pressures if this is deemed necessary. 
     All listed characteristics which are also depicted on the drawings, individually or in combination with each other are being considered essential for the invention.