EP2539128A2

EP2539128A2 - Method for producing a composite pipe

Info

Publication number: EP2539128A2
Application number: EP11710398A
Authority: EP
Inventors: Raimund Rockenbauer
Original assignee: Isoplus Fernwarmetechnik GmbH
Current assignee: Isoplus Fernwarmetechnik GmbH
Priority date: 2010-02-26
Filing date: 2011-02-16
Publication date: 2013-01-02
Also published as: AT509229B1; WO2011103606A2; WO2011103606A3; AT509229A4

Abstract

The invention relates to a method for producing a composite pipe (13) which comprises at least one inner pipe (2), an insulating material layer (8) and a jacket pipe (11), a foamable insulating material being introduced in an insulating material molding section (21) which extends around the inner pipe (2) in an insulating material introduction section by means of a blow gun, the insulating material being molded in an insulating layer molding section to give the insulating material layer (8) and the jacket pipe (11) being applied around the molded insulating layer (8), and the composite pipe being heated in the insulating layer molding section, the insulating material introduction section and the insulating layer molding section being heated or cooled to a defined temperature range.

Description

Method for producing a composite pipe

The invention relates to a method for producing a composite pipe, which comprises at least a core tube, an insulating layer and a jacket tube, wherein in a Dämmstoffausformungsbereich, which extends around the core tube, a foamable insulating material is introduced in a Dämmmaterialinbnngungsbereich by means of pistol, the insulating material in a Dämmmaterialausformungsbereich forms to the insulating layer and the insulation layer is formed in a Dämmschichtformbereich and the jacket tube is applied to the molded insulating layer, wherein the composite tube is heated in Dämmschichtformbereich.

According to the prior art, polyurethane is mostly used as insulating material for the insulation layer. The polyurethane is introduced in fluid form into an area to be filled by means of spray guns and solidified under an increase in volume.

In order to form a uniform insulation layer with respect to the cell structure, the solidification of the sprayed-on polyurethane has to take place within a certain temperature range. If the region in which the insulating layer is formed is too low in temperature, it is almost impossible to provide a high quality insulating layer, i. with a low thermal conductivity in a homogeneous cell construction and at a low specific gravity.

Devices with which compound pipes are produced in prior art processes have the disadvantage that with a "cold" device only after a start-up period the production of high-quality composite pipes can be fully absorbed, in particular in cold regions and In moderately heated production halls, the so-called start-up of a "cold" device is a difficult process.

AT002992 describes a method according to which the foamed insulating layer is formed with heated forming jaws. The invention discussed herein discloses a method which allows for the formation of a uniform, high quality cell structure in the context of manufacturing a composite tube. According to the invention, this is achieved by heating or cooling the insulating material introduction region and the insulating layer molding region to a defined temperature range.

The cooled or heated area in which the insulating layer is formed may be closed by a housing, so that heating or cooling of this area relative to the surroundings can be performed in an effective manner. Compared to prior art methods, the method according to the invention has the decisive advantage that the above-mentioned problems with regard to start-up of a production device no longer exist.

The insulating material can be introduced by means of a gun in the Dämmstoffausformungsbereich. The invention does not exclude that the insulating material is sprayed with other, known in the art devices in the Dämmstoffausformungsbereich or applied to a befindlicher in Dämmstoffausformungsbereich part of the core tube.

A further development of the method according to the invention can consist in that the insulating material layer is formed in its surface area by shaped pieces located in a closed position and the shaped pieces are heated or cooled so that the heated molded pieces heat or cool the insulating material forming area.

The fittings located in a closed position can serve to spatially limit an expansion of the insulating material which cures to the insulating layer. A hardening of the insulating material to an insulating layer may be associated with an increase in volume. The Dämmstoffausformungsbereich, in particular the fittings can be heated or cooled in the context of this invention by a method known in the art and by means of suitable device. A heating of the area or the fittings can be carried out for example by an infrared heater.

Likewise, the device may comprise heating or cooling devices, by means of which heating or cooling media are passed to the fittings. The fittings can also be washed by the heating and cooling media.

Another embodiment of a heater is an electrical resistance heater.

By heating or cooling the Dämmstoffausformungsbereiches or the fittings is substantially that local area in which the hardening of the applied in fluid form insulating material takes place to the insulating layer, heated or cooled to a defined temperature range. The Dämmstoffausformungsbereich can extend in the sense of a progressive production starting from the gun through which the insulation layer is introduced in fluid form, up to the last seen in the direction of production molding.

The formation of the insulating layer of the insulating material preferably takes place in a temperature range of 0 to 100 degrees Celsius, preferably in a temperature range of 10 to 40 degrees Celsius when using polyurethane insulating material to ensure a uniform formation of the cells. A uniform formation of the cells ensures in relation to the material properties of the insulating material very good and on the extent of the insulating layer constant insulation properties. Such an insulating layer further has a substantially constant specific gravity.

As a rule, heating or cooling of the fittings is necessary if the room temperature of the premises is below or above the temperature range in which curing of the insulating material preferably takes place.

The invention does not exclude that the heating or cooling of the fittings is limited to a limited period of time. Such a period can For example, be that period in which the production of composite pipe is started according to the inventive method on a plant. This period may be limited by the time at which the room temperature and parts of the apparatus for producing the composite pipes is heated to a defined temperature range by those heat of production which arises during the production of the composite pipes.

The inventive method is characterized in that the composite pipes, which are characterized by a high-quality insulation layer, can be produced even at low temperatures. A plant for carrying out the method according to the invention can be formed in that the Dämmstoffausformungsbereich and / or the fittings in Teilbreichen have different temperatures. The different temperatures can be defined by the different states of aggregation of the insulating material or the insulating layer made of the insulating material.

The method of the present invention may include placing a release liner around the core tube and defining the insulation curing area as a space extending between the inside of the release liner and the outside of the core tube such that the insulating material is introduced into the space in fluid form. A release film can prevent, for example, a bond between the insulating layer and the fittings. The insulating material may include adhesive substances, which may cause at least partial bonding with the fittings during curing of the insulating material.

The release film can thus be formed into a tube, wherein a compound of the longitudinal edges of the release film is produced by welding and / or gluing.

Preferably, such a shaping of the release film to a hose takes place immediately after the transfer of the release film around the core tube and before the introduction of the Dämmmaterials in the space defined by the release film and the core tube. The invention also includes that the release film in the form of a tube is placed around the core tube.

The insulating layer in its surface area and optionally the release film can be formed by the fittings smooth or wavy. By heating the fittings is achieved that the curing of the insulating material proceeds substantially under optimum environmental conditions. The ambient conditions essentially relate to the temperature, in a broader sense dependent parameters such as the humidity.

The curing of the insulating material in a preferred temperature range can also facilitate a shaping of the insulating layer in the surface region and optionally the release film. Possible shapes of the insulating layer in the area subjected to the process and the release film is a wavy or smooth shape. The shaping can be predetermined by the subsequent storage on a cable reel in a rolled-up state of the composite pipe or in a substantially unbent state.

The invention discussed herein does not exclude that the surface of the insulating material layer and optionally the surface of the release film having formations such as notches at predefined intervals. A special form of a wavy shape of the surface of the insulating layer or optionally the surface of the release film may be a half-wave shape.

The insulation layer in its surface area and optionally the release film can be formed in a first sub-step and in a first sub-area, in a further sub-step in a further sub-area. The invention also relates to methods according to which the insulating layer is formed in its surface area and optionally the release film in a continuous process.

The jacket tube can be applied to the molded insulating layer or optionally to the molded release film. The inventive method may be characterized in that the jacket tube is applied in fluid form to the molded insulation layer or optionally on the molded release film, the jacket tube on the insulation layer or optionally solidifies on the release liner and the outer surface of the jacket tube has a similar surface shape as the surface of having molded insulation layer or optionally the molded release film.

The jacket tube may for example be made of a material which is applied in fluid form to the molded insulation layer or optionally to the formed release film and solidifies on the molded insulation layer or on the molded release film. In composite pipes for district heating, the jacket pipe is made of polyurethane or a similar plastic. The inventive method may be characterized in that by forming the insulation layer and optionally the release film, the insulating layer and optionally the release film has a preferred temperature range for applying the material of the jacket tube in fluid form, so that the material of the jacket tube to the shape of the molded insulating layer or the shaped release film adapts.

The jacket tube can be applied for example by means of extrusion on the molded insulating layer or optionally on the molded release film.

By heating or cooling the fittings, the process parameters and thus the formation of the insulating layer of the insulating material can be influenced.

By heating the fittings, the formation of the insulating layer of the insulation material can be accelerated or delayed.

In the context of this description, the production rate is mentioned as a process parameter.

The invention discussed here also relates to an apparatus for carrying out the production of a composite pipe, wherein the apparatus comprises at least one Storage drum, a roller system, a supply spool, a gun, fittings, a Mantelrohraufbringeinheit and a strip trigger, the device comprises a heated or cooled Dämmmaterialeinbringungungsbereich and / or Dämmmaterialausformungsbereich The Dämmstoffausformungsbereich can be essentially defined by a housing, which is the method according to the invention To be produced composite pipe passes through openings. The housing, in a preferred embodiment, includes prior art devices to optionally occlude the openings. The device according to the invention can be characterized in that the fittings are heated or cooled. The fittings are preferably placed within the housing defining the area.

The heating or cooling of the fittings and / or the Dämmstoffausformungsbereiches done by a heat or cooling source. With respect to the entire manufacturing process, heating of the region or of the shaped parts by means of infrared appears to be particularly advantageous.

The device may also include other heat sources through which the core tube and / or optionally the release film is heated. Such heat sources may be integrally formed in elements of the device, such as guide elements. To heat the release film, for example, the funnel can be heated.

FIG. 1 shows a cross-sectional view of an embodiment of a composite tube produced by the method according to the invention.

Figure 2 shows a cross-sectional view of another embodiment of a composite tube, which was prepared by the process according to the invention. Figure 3 shows a schematic representation of a plant for producing a composite pipe according to the inventive method. FIG. 1 shows a sketch of a composite tube 13 which comprises at least one core tube 2, an insulating material layer 8 arranged around the core tube 2 and a jacket tube 11 arranged around the insulating material layer 8. The core tube 2 is connected to the insulating material layer 8, the insulating material layer 8 with the jacket tube 11. The insulating material layer 8 facing surface of the core tube 2 and / or the jacket tube 1 1 may be structured so as to produce a bond between the core tube 2 or casing tube 1 1 and the insulating material layer 8.

FIG. 2 shows an embodiment of a composite pipe comprising a release film 5. To the core tube 2, the insulating material layer 8, the insulation film, a release film 5 to the release film 5, the jacket tube 1 is arranged. The release film 5 is arranged as a tube 6 in the composite tube 13. The insulating layer 8 or the release film 5 facing surface of the core tube 2 and / or the jacket tube 1 1 may be structured so as to produce a composite of the core tube 2 and the jacket tube 1 1 with the insulating layer 8 and the release film 5.

FIG. 3 shows a device 50 for carrying out the method according to the invention, wherein in a preceding method step the core tube 2 is unrolled from a supply roll 1. For this purpose, a roller system 3 is used to drive the core tube 2.

The release film 5, which is mounted on a supply reel 4, is unrolled from the supply reel 4 and formed into a tube 6 by an openable in an upper portion, heatable funnel shape 22, wherein the one elongated side edge 20 with the other not shown in Figure 3 elongated side edge of the pulled through the funnel shape 22 separating film 5 is connected. In the Dämmstoffausformungsbereich 21, the insulating material is introduced by means of a heated gun 7, which is positioned in the upper portion of the open funnel shape, in the extending between the release film 5 and the core tube 2 space. In a molding press 14, which is formed by a top arranged circumferential belt 16 together with upper moldings 9 and a bottom arranged circumferential belt 17 together with lower moldings 10, the Insulating layer 8 is formed in its surface area by the molds 9, 10 located in the closed position and by the fittings 9, 10 which are cooled or heated, cooled or heated. The surface of the insulating material layer 8 is formed smooth by the fittings 9, 10. The formation of the surface of the insulating layer takes place in a continuous process.

According to the invention, an insulating material forming region 21, which extends from the gun 7 to the last molding seen in the production direction in the closed position, is heated or cooled to a temperature in a defined temperature range of 0 to 100 degrees Celsius, preferably 10 to 40 degrees Celsius.

In the device 50 shown in FIG. 3, the insulating material forming region 21 is defined as the region viewed in the production direction from the mold pieces 9, 10 located in the gun 7 and by the last closing position.

The fittings 9, 10 can be heated by a heat source, whereby a temperature range is created in the region 21, which is optimal for forming the insulating layer 8. In this case, the fittings 9, 10 can also be heated or cooled to different temperatures of the temperature range. By the respectively located in the closed position upper mold piece 9 and the lower mold 10, the tube 5 and the insulating layer 8 is formed, wherein the surface 18 may have a corrugated or smooth shape after molding in the molding press 14. The device 50 shown in FIG. 3 permits continuous shaping of the tube 6 and the insulating material layer 8.

By means of an extruding unit 12, the jacket tube 11 is applied to the tube 6. The surface 19 of the jacket tube 11 is similar to the surface 18 of the release film. The strip trigger 15 forms the surface 19 of the jacket tube 11 and ensures the movement of the composite tube thirteenth

Instead of the heat source, a cooling device can be used as needed.

Claims

1. A method for producing a composite pipe (13) comprising at least one core tube (2), an insulating layer (8) and a jacket tube (1 1), wherein in a Dämmstoffausformungsbereich (21) which extends around the core tube (2) in that a foamable insulating material is introduced by means of a gun in an insulating material application area, the insulating material is formed in an insulating material forming area to the insulating layer (8) and the insulating layer (8) is formed in an insulating layer forming area and the jacket pipe (11) is applied around the molded insulating layer (8) is, wherein the composite pipe is heated in Dämmschichtformbereich, characterized in that the Dämmmaterialeinbringungungsbereich and Dämmschichtformbereich is heated or cooled to a defined temperature range.

2. The method according to claim 1, characterized in that the insulating material is introduced by means of a heatable gun (7) in the Dämmmaterialeinbringungsbereich.

3. The method according to claim 1 or 2, characterized in that the

Heating or cooling of Dämmmaterialeinbringungsbereiches and / or Dämmschichtformbereiches by the heated or cooled moldings (9) by means of thermal radiation.

4. Device (50) for carrying out the production of a composite pipe (13) according to one of claims 1 or 2, comprising at least a storage drum (1), roller system (3), a supply reel (4), a pistol (7), fittings ( 9), a jacket pipe application unit (12), a tape stripper (15), characterized in that the apparatus (50) comprises a heated or cooled insulation material introduction area and a heated or cooled insulation material formation area.

5. Device (50) according to claim 3, characterized in that the

Pistol (7) is heated.

6. Device (50) according to any one of claims 4 or 5, characterized in that the device (50) comprises a further heat source through which the core tube (2) and / or optionally the release film (5) are heated or cooled.