DK174554B1 - Hose piece for lining a pipe string, method and apparatus for making the hose piece, and method for repairing an existing main pipeline section by means of the hose piece - Google Patents

Description

in DK 174554 B1

The invention relates to a hose piece for lining a pipe string, in particular a sewer installation, a method and an apparatus for making the hose piece, and a method for repairing an existing main pipe section by means of the hose piece.

From U.S. Patent Nos. 3,927,164, 4,064,211, 4,394,202, and 2,794,758, the United States Patent Nos. 4,014,757

2,084,686 and 1,580,438 and from European Patent Specification no.

10 0576 various methods and apparatus are known for the erection and repair of leaning pipelines, pipelines available only at one end and for repair of sewer mains.

Most of these and other known methods for inserting rigid or semi-rigid pipe sections into an existing underground pipeline present the disadvantage that, due to said rigidity, they must be inserted into straight-line or near-straight-line pipelines.

This means, for example, that such known methods are limited to use in connection with sewer mains because they usually have rectilinear pipe sections extending between manholes. In contrast, these methods are not suitable for use in repairing the numerous plug lines extending from the main sewer lines to the individual buildings. Such plugs often run with curves or bends where a rigid or semi-rigid plastic pipe cannot be used, and in addition, plugs are usually not available via sewer wells at the ends, so that conventional pipe replacement methods requiring access through sewer wells or the like at both ends, are extremely expensive. In connection with the conventional pipe replacement operations, large excavations must be made at one end of the plug line to be created or repaired to make room for insertion of the new rectilinear plastic pipe sections at the replacement. Such a wide excavation next to the building served by the mains cable or at the other mains end where it cuts the sewage mains is often impractical and expensive.

10 Furthermore, most known methods for replacing or repairing existing underground pipelines require access to the pipe section to be repaired at both ends of the section, and this is not possible for a plug line which by definition intersects a main line at one point. that is not normally accessible through a sewer well.

Another disadvantage of the aforementioned known methods is that once the pipe is in place in the existing pipeline, it is very difficult to locate the exact positions where the plug lines intersect the main pipe so that access ports can be cut in the new pipe section. for recording the plug wires. This is especially true if the new pipe section has a sufficient thickness of material and therefore a sufficient curvature to withstand, in itself, typical hydraulic pressures and earth pressures.

The invention has for its object to alleviate said disadvantages 30 of the known methods and apparatus of the specified kind.

3 DK 174554 B1

The invention thus makes it possible to feed an existing pipe string by means of a liner having the shape of a diminished or folded hose piece. The hose piece is substantially rigid at ambient temperature, but is made flexible by heating before installation. By the invention, it is ensured that the tubular shaped casing does not inadvertently expand from said diminished mold and thus make installation difficult in the existing pipe string. This 10 happens by making the liner so it has a memory! In for the diminished form. Thus, when the liner is heated to make it flexible, it will retain its shape during insertion into the pipe string and will only expand toward the pipe string when heat and pressure are applied internally. After cooling, the tubular liner will retain its expanded shape where it abuts the pipe string.

The invention thus provides the following features: 1. A hose piece suitable lining of an existing underground pipeline which is particularly suitable for use in non-rectilinear building sewer pipes and sewer pipe lines intersected by sewer pipes 2. A method and apparatus for manufacturing said hose piece suitable for use in non-straight-line underground pipelines or intersected by plugs, and 3. A method for inserting a new hose piece into an existing underground pipeline, especially a non-straight-line pipeline or a pipeline intersected by plugs.

The invention is further explained below in connection with the drawing, in which: FIG. 1 is a cross-sectional view of a conventional expanded circular tube in expanded circular form; FIG. 2 is a perspective view of the tube of FIG. 1 and an apparatus for clamping the tube for reeling on a coil; FIG. 3 is a cross-section through the clamped tube of FIG.

2 along line 3-3, FIG. 4 is a schematic representation of a method of inserting the tube of FIG. 2 and 3 during flushing and heating through a sewer well to replace a pipe section in an underground pipeline; 5 is a partial section through an apparatus for expanding the clamped plastic tube of FIG. 2 and 3 and flushing of the tube after insertion in the FIG. 4, consisting of 25 sewer mains. 6 shows a modified embodiment of the apparatus of FIG. 5, 30 FIG. Ί is a section through a typical building sewer line extending between the building and a sewer main line, showing a method according to the invention to 5 DK 174554 B1 in FIG. inserting a first tube into an existing sewer line, FIG. 3 is a section through a preferred embodiment 5 of the plastic tube of FIG. 1 in the folded state for insertion into an existing underground pipeline; FIG. 9 is a schematic elevation of an apparatus for producing the plastic tube of FIG. 1 in the FIG. 8 shows the folded shape shown in FIG. 10 is an enlarged view of the calibrator of the apparatus of FIG. 9, 15 FIG. 11 is an elevation of a single calibration plate in the calibrator of FIG. 10, seen in the direction of arrow 11-11, in i: fig. 12 is a plan view of a folded end portion of FIG. 8 shows a plastic pipe with an attached terminal block 20 for penetrating the pipe into an existing pipe and for narrowing the pipe end for pressure application in the pipe interior for expansion. 13 is a cross-section through the stirring portion of FIG. 12 along line 13-13, FIG. 14 is a plan view of an embodiment of FIG. 7 shows a cable / disk apparatus according to the invention for penetration of the folded plastic tube of FIG. 8 in a plug line, shown in working order; FIG. 15 shows the apparatus of FIG. 14 in squeezed condition for insertion into a plug line, 6 DK 174554 B1 fig. 16 is a side view of the apparatus of FIG.

14 and 15, FIG. 17 is a side view of a plugging tool for plugging one end of the one shown in FIG. 8, after rounding the end for use in applying fluid of heat and fluid pressure to the interior of the pipe; FIG. 18 shows the implement of FIG. 17, front view, fig. 19 shows one end of the plastic tube with the implement of FIG. 17 and 18 inserted into the tube and clamped in place by a chain actuated clamping means; 20 shows the chain clamping member of FIG. 19 before its on; fitting to the tube and plug of FIG. 19, 20 FIG. 21 is a cross-section through the clamped chain clamping tool and plastic pipe of FIG. 19 along line 21-21, FIG. 22 is a longitudinal section through the front end portion of the plastic tube of FIG. 8 with end clamp applied in FIG. 12 25 and 13 and with the remainder of the tube in expanded and curved condition, and with a cutting tool according to the invention inserted into the rounded tube portion to separate the clamped tube from the rest of the tube; 23 is a cross-section through the tube and cutting tool of FIG. 22 along line 23-23, FIG. 24 is a side elevational view of an end heating apparatus for heating an end portion of the plastic tube for reworking the end portion, shown inserted on a folded end portion of the plastic tube of FIG. 8, FIG. 25 is a perspective view of an inflatable end capping tool for plugging or narrowing the end portion of the plastic tube instead of the end clamping member of FIG. 12 and 13 for expanding and rounding the folded plastic tube, FIG. 26 is a partial sectional side view of the inflatable tube of FIG. 25, 15 FIG. 27 is a schematic representation of the insert of the inflatable plugging device of FIG. 25 and 26 in the plastic tube in its expanded and rounded condition; 28 is a schematic view similar to FIG. 27, 20 but showing the plastic tube after a new folding with the inner inflatable plugging tool in the collapsed condition; 29 is a schematic representation of the use of the inflatable plugging tool of FIG. 25 and 26 during insertion of the plastic tube into a plug line, in FIG. 30 is a schematic representation of another use of the inflatable plugging device of FIG. 25 and 26, FIG. 31 is a schematic representation of the use of the implement of FIG. 25 and 26 in accordance with the method of FIG. 30, 30 8 DK 174554 B1 fig. 32 is a schematic representation of a third use of the inflatable plugging device of FIG. 25 and 26 for expanding and rounding the collapsed plastic pipe after its insertion into an existing underground pipeline; 33 is a schematic representation of a pipe head conduit section and a cutting line conduit therein, and showing 10 a modified method of penetrating the plastic pipe of FIG. 8 in the repair cord, FIG. 34 is a schematic view of an end portion of the folded plastic tube of FIG. 8 and showing a method for releasing the traction cable from the front end of the pipe after its introduction into an underground pipeline; FIG. 35 is a view of FIG. 34 is a schematic diagram 20 showing another method of releasing the tow cable from the plastic tube after its insertion into an existing underground pipeline; FIG. 36 is a cross-section through the intersection of a main pipe 25 and a plug line after the insertion and expansion of the plastic pipe of FIG. 8 in the repair head pipe and showing a method for locating and cutting an opening through the newly inserted plastic pipe for restoring the connection between the plug pipe and the pipe head pipe; FIG. Fig. 37 is a schematic side elevational view of a method and apparatus for folding a molded tubing made of a profile formed for insertion into an existing underground pipeline; 3SA-E are cross sections through the tube of FIG. 37 along li-: 5 the kidneys respectively. 38A-38A ... 38E-38E, fig. 39 is a side elevational view of a detachable one-terminal and an attached and detachable tow cable for use in clamping the front end of the folded tube of FIG. 8 during its insertion; FIG. 40 is a top view of the end clamp of FIG.

39, and FIG. 41 is a top plan view of the removable wedge portion of the clip of FIG. 39th

FIG. 1 shows a pipe in the form of a hose piece 10 which is used for rebuilding, repairing or replacing 20 pipe sections in existing underground pipelines, such as sewer pipes, according to the invention. The pipe 10 is made of a thermoplastic material such as PVC, in particular a material having a normal stiffness and wall thickness to be able to provide a sufficient curvature to withstand the external soil pressure and hydraulic pressure to which the pipe can be subjected underground. Such thermoplastic tubes can be made flexible by heating to temperatures of, for example, 94 ° C and above in the case of a PVC pipe. Characteristic of the pipe 10 is that it is structurally rigid at typical ambient above-ground and underground temperatures, but becomes flexible and malleable to various profiles upon heating or reheating. Another characteristic of the plastic material is that it has a shape retention tendency, i.e. if it is manufactured with a separate profile such as a circular tube profile and then heated and squeezed or folded and then cooled to stabilization in the folded state, and then reheated without obstacles, it will seek to regain its original round pipe profile. If the tube is initially manufactured in, for example, squeezed and folded condition of the one in FIG. 3 and 8, and then heated and expanded by applying 10 internal pressure to the rounded profile and then cooled and stabilized in the rounded profile, it will seek to regain its original folded profile, if it is then recovered without obstructions. This property of the thermoplastic tube is advantageously used for certain embodiments of the invention.

A conventional and marketed pipe of a type suitable for use in the invention is a PVC pipe having a standardized dimension ratio (outside diameters divided by wall thickness} within the range 13-65 for use as underground pipelines such as sewer pipes, water pipes etc.

Although in the most preferred embodiment of the invention, the thermoplastic tube is manufactured in the embodiment of FIG. 8, as discussed in connection with the apparatus of FIG. 9-11, certain features of the invention may also be practiced using a thermoplastic tube manufactured in circular tubular form. FIG. 2 shows an apparatus 11 for reshaping the conventional PVC pipe 10 which has been manufactured with a circular profile; and FIG. 3 shows the tube after the reshaping by flattening and folding by means of the apparatus of FIG. 2. The PVC pipe is heated in a conventional manner, such as by means of a heating element 11a, which may be a thermostatically controlled steam box or a housing containing thermostatically controlled * electric heating elements. Passing the original round tube 10 through the heating box 11a heats the tube to a sufficiently high temperature to make the tube plastic or flexible. Thereafter, it is flattened or preferably collapsed in a folding apparatus 11 to reduce the overall cross-sectional dimension of the pipe so that it can easily be pulled into an underground pipeline with the same or slightly larger inner diameter than the original outer diameter of the thermoplastic pipe. FIG. 3 shows the thermoplastic tube 10a after folding.

15 A practical tube folding apparatus is shown in more detail in FIG. 31 and 38A-E, wherein the round tube 10 after passage through the heating box 11a is first flattened by a pair of opposed flattening rollers 60 and 61 and then passed under a folding wheel 62 under the gradual support of three 20 different sets of folding rollers 63, 64 and 65. The fold roll pair 63 is arranged to cooperate with the fold wheel 62 to begin folding the tube 10 into U shape. Thereafter, the three fold rollers 64 continue the folding process arranged in a U half shape to cooperate with the fold wheel 62. Finally, 25 is the set of four fold rollers 65 arranged in a U shape to cooperate with the fold wheel 62 to complete the folding of the tube 10 to the U shape, For example, the collapsed tube is passed through a constricting mold 66 during cooling to stabilize the tube in its U-shape so as to maintain a non-molding tendency. From the mold 66, the collapsed tube can either be stored for prescribed lengths or passed through a steam tube for reheating and bending or making for direct insertion into an existing pipeline.

12 DK 174554 B1

Alternatively, after flattening and before folding, the tube may be flushed in flat state in a heating box 18 as shown in FIG. 4. Thereafter, the flat coiled tube 5 may be reheated in the heating box at the point of use and then withdrawn from the heating box and collapsed as previously described just before insertion into the pipeline to be repaired.

In some applications, it is also possible to insert the thermoplastic tube into an existing pipeline in the flattened state, especially if the thermoplastic tube in its circular state has a substantially smaller outer diameter than the inner diameter of the pipeline to be repaired. However, it is most preferred that the thermoplastic tube be inserted into an existing conduit in an axially folded shape as shown in FIG. 3, FIG. 8 or FIG.

38E. Of all these forms, the shape of FIG. 8 for the reasons set out below.

20

As mentioned, the thermoplastic tube manufactured in circular form has a shape retention tendency that seeks to return it to its round shape when reheated after folding. Therefore, when it is necessary to reheat the folded pipe to make it pliable for insertion into an existing pipeline, the pipe will therefore seek to recapture its circular shape, possibly prematurely, if not prevented therein. Therefore, it is primarily preferred for this reason that the thermoplastic tube is first manufactured in the desired folded form. Then, when the collapsed tube is reheated to make it flexible for insertion into an existing pipeline, the tube will maintain its folded profile until it is fully inserted into the existing pipeline and ready for reshaping into the circular shape.

Whether the thermoplastic tube is manufactured in circular or folded condition, the tube must be folded when ready for insertion into the existing tube | wire. It is also preferred that the thermoplastic tube be coiled in hot state and therefore be made flexible on a bearing coil such as the one shown in FIG. 4 shown in coil 12.

10

The coil 12 with the folded thermoplastic tube is stored in a housing or heating box 18 provided with a thermostatically controlled heater 24 for heating the interior of the box and thus by the coil 12 to make the folded tube material 10a flexible if required. Preferably, the heat case 18 is also equipped with an air circulation system 19 to prevent a heat layer formation in the heat box and thereby ensure that the coil with the folded pipe will be evenly heated. The heating box 18 is preferably mounted portable and 20 is shown in FIG. 4, mounted on the plane surface of a truck 20 for transport to a laying point. A smaller design of the heating box can be wheel mounted and transported manually for use in small inaccessible places of use, such as plugs. In all cases, mechanical means are provided for rotating the coil 12 for winding or unwinding of material on the coil. The heater box 18 is provided with an inlet door 21 and optionally also with a downpipe 22 and a roller 23 to facilitate the insertion of the folded thermoplastic tube into an underground disc duct through a vertical inlet opening, such as a sewer well 16, to the existing underground sewer pipe. -direction 14.

14 DK 174554 B1

According to the invention, the heating box 18 can be transported to an opening at the repair site, such as a sewer well 16, with access to an underground sewer main conduit 14. The end of the constricted pipe 10a is connected to a draw cable 5 26 provided from an adjacent opening in the standing pipeline, such as another (not shown) sewer well, and is connected by a clamping member 28 to the front free end of the new pipe. The new pipe is made flexible by heating the coil 12 in the heating box 18 by means of the heater 24. Thereafter, the pulling cable 26 is activated, for example from a play at the next sewer well downstream of the well 16, to extract the flexible folded pipe 10a from the coil 12. through the downpipe 22 and around the roller 23 into the existing pipeline 14 to 15 the next well. After insertion of the folded new tube, it is heated and expanded to form a substantially circular cross-sectional profile of a tube acting as a thick-walled, rigid workpiece with sufficient flexural strength to withstand external water pressure and soil pressure.

FIG. Figure 5 shows a method for expanding the reduced-dimension tube after the tube is drawn into the original pipeline to be repaired. According to this method, a pair of plugs 30 and 32 are inserted at each end of the folded tube when at least the tube ends are in the heated flexible state. The plug 30 is inserted at the front end of the new pipe section or pulling after the separation from the draw cable. Each of the plugs 30 and 32 is provided with circumferentially expandable packing rings 34 arranged for releasably close closure engagement with the original pipeline 14 and the new pipe section 10a. The gaskets 34 are inflated via pressure lines 36, for example compressed air lines, which are connected to (not shown) control means above the ground surface. The plug 30 has a continuous inlet channel 38 for introducing into the new pipe section an expandable medium such as fresh steam or hot water. The duct 5 33 is provided with a suitable control valve 40 and a pressure gauge 42 and an expansion valve 44. The plug 32 has a through discharge duct 46 which communicates with the area between the two plugs and is provided with a valve at 48.

10

The newly inserted folded pipe section with inserted plugs at the opposite ends of the pipe is then heated internally by passing fresh steam through the small ducts provided by the folds in the new pipe section as shown in FIG.

8. The valve 48 at the downstream end of the pipe section is opened so that the entire stretch of the new pipe section is heated. Then the valve 48 is closed and steam is continued to be pressurized through the plug 30 to pressurize the folded tube and reshape it and expand into a circular shape. If the new tube is made folded, it should be cooled or cooled after assuming its circular shape while maintaining internal pressure such as the cooling air pressure so that the tube assumes its circular shape. This step is not necessary if the tube is produced with a circular profile unless the tube is expanded or extended beyond its original diameter during the re-forming process.

If no internal ducts are provided in the folded 30 new pipe, for example when the new pipe as shown in FIG. 3 is folded to absolute flatness, the new pipe must be heated externally, for example by passing fresh steam through the existing pipe, before plugs 30 and 32 are inserted at the ends of the new pipe. Once the entire stretch of the new tube is heated, the plugs 30 and 32 can be easily inserted into the opposite ends of the tube, the valve 48 is closed, and fresh steam or hot water is introduced through the plug 30 to expand the folded tube and reshape into circular shape.

FIG. 6 shows another embodiment of an apparatus for expanding the cross-sectional reduced tube. The apparatus 10 here comprises a mandrel 50 with an internal heating means 52 for heating the new pipe section to a flexible state. The mandrel 52 is connected to a pulling cable 54 or other means for pulling the mandrel through the existing pipeline. By appropriately heating the mandrel 50 and 15 by exerting the voltage on the pulling cable 54, the mandrel is drawn through the original pipeline while expanding the desired diameter of the new pipe section. By this method, it is clear that the traction cable 54 is adjusted in the new pipe section before being folded for insertion into the existing pipeline.

In a third method of heating, rounding and expanding the new pipe section, hot water or steam is flushed down the existing pipeline to be repaired, along the inserted, with still folded new pipe sections, until the desired temperature is reached at the downstream end. Then, the new pipe section is pressurized with hot water or steam and expanded under pressure to the rounded shape and to the desired diameter.

By way of example, a conventional large PVC pipe whose outer diameter is approx. 1.3 cm smaller than the inner diameter of the main pipe. Further, the PVC-17 provides the aforementioned standard dimension ratios of wall thickness with respect to the outer diameter. The PVC pipe is heated to at least 93-98 ° C and narrowed to that of FIG.

3, FIG. 8 or FIG. 38E. Then, the 5-fold tube is stored on large coils so that it can be driven on the truck to the point of use. During insertion into an existing underground pipeline, the new pipe section is heated again, preferably in the heating box 18, so that it becomes flexible and capable of being easily drawn substantially vertically downward through a deep well and then substantially horizontal through the existing pipeline. . After insertion into this plug, the folded tube is heated and rounded. If desired, it can also be expanded beyond the original circular diameter of the pipe to fit closely to the existing pipeline.

An advantage of expanding the newly inserted thermoplastic tube beyond its original outer diameter is shown in FIG. 36, wherein the existing pipe main conduit 70 to be repaired is cut by at least one sewer plug conduit 74 at the site 72. The new thermoplastic pipe 80 is inserted into the main conduit 70 and rounded and expanded or extended beyond its rounded diameter to closely engage the existing one. In the inner wall of the main conduit 70, a bead or recess 76 is formed at the intersection 72. Fill stone 76 actually indicates the exact location of the opening of the plug conduit to the main conduit. By passing a television camera through the main line, it is possible to determine the exact location of the bead or recess, thereby opening the connector line. Then, a remote controlled cutting tool 78 can be guided along the main conduit 70 to the exact position of the bead 76 and used to cut it from the new pipe section 80 to regain access from the conduit 74 to the main conduit.

Rounding and expanding or stretching of the just inserted thermoplastic tube is provided by the methods already described or as further described below in connection with other embodiments.

Even the flattened and folded thermoplastic tubes as shown in FIG. 3 and FIG. 38E are useful for use in the installation process described, the preferred embodiment of the folded tube 10 is that of FIG. 8. The thermoplastic tube 10 of FIG. 8 is prepared essentially in the folded form shown. It is essentially a collar tube folded along a substantially curved bead length 82 to form a pair of overlapping branches, comprising a long branch 83 and a shorter branch 84. The long branch 83 terminates by a curved or bead-like branch. free end 85 for defining a narrow longitudinal channel 86 through the folded tube. The shorter branch 84 is also terminated at a curved or bead-free end 87 which also defines a longitudinal channel 88 through the tube. Further, the gently folded portion 82 25 defines a channel 89 along the inside of the fold from one tube to the other.

The described bead-like folds and branches are essential to prevent the folding portions of the tube from tearing in the collapsed condition, which might otherwise be the case when the tube is folded completely flat as shown in FIG. 3, especially if the tube is thick-walled. The ducts 86, 88 and 89 are also essential for providing longitudinal ducts for steam or other hot fluid along the entire folded tube for reheating and thus reworking after the folded tube is inserted into an existing underground pipeline. Without such access to the interior of the folders, reheating would be a slow process and very difficult to finish.

The folded tubular shape of FIG. 8 is particularly suitable for use in replacing pipe sections in a sewer line 90 10 as shown in FIG. 7, leading from an inner sector 92 of a pipe main 94 to a building 96. The insertion of a replacement pipe section into such sewer pipes presents special problems due to the nature of the pipes.

15 First, such plugs present difficult access conditions because they often extend under lawns, trees and shrubs and are not accessible via wells. An excavation of the existing power cord for use in repair will therefore be very costly. When inserting 20 a new plug line into an existing underground plug line, there is usually only access from a single narrow vertical excavation off the building, as indicated by 98 in FIG. 7. Such an excavation creates little space for maneuvering or for a larger amount of equipment.

25

Second, sewer lines usually have a much smaller diameter than the mains, and often exhibit sharp curves or bends unlike the mains, which usually extend the rectangle from well to 30 wells. For example, the plug line 90 has a bend at 100 which makes it impossible to insert a rectilinear rigid tube into the existing plug line. In FIG. 7, the sewer pipe 90 extends beneath a lawn 102 to the main pipe 94 at a substantial depth below a street portion 104.

The methods and apparatus described below are particularly suitable for resolving these particular problems by inserting a replacement plug line section into an existing 5 underground plug line from a single small, normal vertical access port. For this purpose, the one shown in FIG.

S shows the fused configuration of the thermoplastic tube.

10 In FIG. 9, 10 and 11 are the folded thermoplastic tubes of FIG. 8, made using a conventional plastic pipe extruder 106 with a vacuum box 108. Tensile means 110, comprising a series of opposing clamping rollers 111 and 112, downstream of the vacuum box 108, pull the extruded and shaped material out of the vacuum box under tension and introduce it into a steam tube. 114 for reheating to a flexible state so that the resulting folded tube can be wound in the folded state on a storage coil 116 which may typically be placed in the heating box 20 18 of FIG. 4th

A press 118 and a mandrel 120 are disposed at the outlet of extruder 106. An air gap 121 of approx. 30-60 cm consists between the downstream end of the press 118 and the inlet to the vacuum box 25 108.

The vacuum box 108 is internally divided by partitions 122 and 123 into three sections. All three sections are filled with water to a water level 124 in box 108. The first section of box 108 is connected to a vacuum source 125. Although the entire vacuum box 108 is under negative pressure due to such a connection, a maximum negative pressure in the box's upstream section 21 DK 174554 B1. A calibration means 126 is disposed in the first section of vacuum box 108. Calibration means 126 designs and maintains the extruded resin material in its desired collapsed form during the cooling and curing of the material. The water in the vacuum box 108 acts as a cooling means, and the vacuum supplied to the box cooperates with the calibration means to maintain the plastic material in its desired folded form until after cooling it is able to maintain the mold without coercion.

10

As shown in FIG. 10 and 11, the calibration means 126 comprises a series of calibration plates 128 arranged in sequence and assembled by means of connecting rods 130 and separated by spacers 132 between the individual plates.

The rods 130 are threaded at the ends and secured by nuts 134. The calibration plate 128 closest to the inlet end of the calibrator is positioned closer together than the more downstream plates due to the greater plasticity of the plastic and the flowability at the inlet portion where it is most needed. to maintain the shape of the extruded material in that calibration member portion. Optionally, the calibration means 126 may also comprise a central tube 136 with apertures 137 for transmitting cooling water to and between the plates 128 for faster cooling of the plastic material.

As shown in FIG. 11, each calibration plate 128 includes an accurate cut-out aperture 138 corresponding to the exact outer shape of the dimension of the shaped and folded tubes retained in the calibration plates. Each plate 128 of the calibration means has exactly the same dimension and shape of the aperture. By comparing FIG. 8 and 11, it is noted that the opening 138 of the calibration plate 128 comprises a short branch 138a corresponding to the short branch 84 of the folded tube and a long branch 138b corresponding to the long branch 83 of the folded tube as well as a rounded one. folded portion 138c corresponding to the longitudinal round fold 82 in the tube.

5

For preparing the tube of FIG. 8, a raw material mixture, such as polyvinyl chloride, is fed to extruder 106 through an inlet funnel 107 where the material is heated to a high temperature of e.g. 180 ° C, after which it is extruded through the press 118, where the very hot plastic material meets the mandrel 120. The press and mandrel are sized to mold the plastic to the desired final dimension and shape of the desired pipe. The plastics material is fed through the air gap 121 into the first section of vacuum box 108 and then through the calibration plates 128. The plastics design and maintain the plastics material in the shape and dimension of the calibration plate apertures 138.

20 At the first inlet of the plastic material into the calibration means, it is very hot and rather fluid, which is why the calibration plate 128 here is quite close together to maintain the desired shape. The vacuum in the mold box holds the molding material against the outer periphery of the aperture 25 138 during the cooling water cooling of the molding material. If desired, compressed air can be injected from a source 140 into the mandrel 120 and thence through the inner ducts 86, 88 and 89 of the folded plastic tube to ensure that the plastic material does not completely collapse and to maintain the tube shape. At the time the mold material reaches the downstream end of the calibration means 126, it is cooled to a significant degree and can maintain its own shape under the tension produced by the pull rollers 110. These rollers pull out the folded plastic pipe from the vacuum box as a continuous strip. From the calibration plates, the strip migrates through the second and third chambers of the vacuum box where the material gradually hardens. At the time the strip 10 leaves the vacuum box 108, it is cooled, rigid and has essentially the same as in FIG. 8. The rollers 110 control the thickness and other dimensional parameters of the folded tube.

10 From the pull rollers 110, the collapsed strip is passed through the steam tube 114, where a source of steam 115 is fed through an inlet opening 117 for reheating the strip to a flexible state so that it can be rewound on the storage coil 116.

15

The number and spacing of the plates used in the calibration means is a function of the rate of extrusion as determined by the drawbar and the desired thickness of the finished pipe.

20

As previously mentioned, the storage spool 116 for the folded tube 10 can be placed in the position shown in FIG. 4 to be transported to and used in a place of use.

25 For inserting the FIG. 8, a thermoplastic tube shown in an existing sewer pipe 90 is first provided, as shown in FIG. 7, a vertical excavation 98, preferably as close to the relevant building 96 as possible, to expose the plug conduit.

Then, the length of the plug line section to be replaced or repaired is determined by inserting a flexible fiberglass rod into the plug line at the excavation site 98 and passing the rod through the plug line until it intersects the sewer head line 94. the rod inside the plug line at the inlet opening, after which the rod is retracted and measured 5 to determine the length of the plastic tube 10 required for the repair work. If you know the lengths of a number of plugs to be repaired, the folded pipe 10 can be pre-cut corresponding to the respective lengths, either at the manufacturing site or some other distance 10 from the place of use. Then, the pre-cut lengths can be transported to the current insertion point of use.

Alternatively, the required lengths may be cut at the work site from the coil 116 or 12 (Fig. 4) within the heat box 18 transported to the work site 18. If the excavations 98 are not available for the truck 20 on which the heat box 18 is mounted, they may be required. lengths of the plastic tube 10 are stored on other smaller coils within (not shown) smaller wheel mounted heat boxes and driven to the respective places of use. Such a "mini heat box" 140 is shown in FIG. 7 and accommodating a coil 142 for the folded tube 10.

Alternatively, the prior measurement and cutting of the required lengths of the folded plastic tube 10 can be avoided by simply heating the folded tube within the heating box 140 and passing it into the existing plug line until the new folded tube reaches the intersection site. with the sewer head line 94, after which the pipe 30 can be cut off at the coil.

If the folded plastic pipe 10 is pre-cut to specific lengths at the manufacturing site, the cut lengths of pipe can be transported to the different applications and heated there for introduction into the existing plug line in a steam pipe as in FIG. Pipes 114 can be made of canvas or metal with flexible 5 ends of textile or equivalent materials which can be bonded around the folded plastic pipe to hold the steam within the steam pipe. Such pipes are lightweight and easy to transport to a place of use and can be 6 m long or more. For use in the field, a canvas vapor tube is preferred over metal for weight reasons.

If the sewer line is rectilinear and its access opening at the excavation site is close enough to the ground surface, or if the excavation is wide enough, it may be possible to insert the required length of the folded plastic tube 10 into the existing plug line by simply pushing the new pipe section into the existing plug line until the front end reaches the main line. However, this is usually not possible because the new pipe must be able to pass a bend at the excavation site or along the plug line or both places. In these cases, it is necessary to heat the normally rigid folded plastic tube to make it longitudinally flexible to pass the bends and to be able to pull 26 DK 174554 B1 | For example, a cable is connected to the front end of the new plug line. The cable is routed around a disk at the connection point between the plug line and the main line and then back to the input line of the plug line. By exerting a traction force on the traction cable from the inlet opening at the excavation 98, the new pipe can be drawn along the full length of the existing plug line. This approach requires the use of specialized tools. First, the front end of the new plug line must be clamped to 10 to limit the size of the ones shown in FIG. 8, to provide an internal pressure setting on the folded tube after its insertion into the existing plug line and so that hot fluid can still flow through the folded tube 15 to heat it over its entire length and thereby making it pliable for expansion and rounding. To produce this constriction, an end clamp member 144 as shown in FIG. 12 and 13 and FIG. The end clamp member 144 comprises a pair of rigid metal plates in the form of a top plate 145 and a bottom plate 146. Both plates have forward projecting nose portions 147 with confluent cable, connecting holes 148. A second pair of confluent holes 149 extends through the two plates behind the cable hole 148 for receiving a clamping bolt 150 which also extends through confluent boreholes 151 through the folded plastic tube 10.

For mounting the end clamp 144 on the front end of the folded plastic tube 10, it is heated to make it flexible, for example in an end heater 152 as shown in FIG. The end heater 152 comprises a thin-walled rigid tube 154, one end of which is closed by an end plate 156 with a central inlet port 157 with a damoslana connection 158. The upper heat spring 152 opposite 27 DK 174554 B1 connection 158. The opposite end of the heater 152 comprises a flexible fabric wrapper 160 with a connection band 162 for enclosing the tube 154. The free end of the shroud 160 can be bonded around the folded plastic tube 10 so that 5 can escape steam at the connection site 164 so that the entire end portion of the tube can be heated to a desired temperature by injecting steam into the tube through the length of the tube 152 is approx. 60 cm for most applications, but may be shorter or longer a total of 10 after use.

When the front end of the pipe 10 has become pliable, the clamping plates 145 and 146 are attached to the end of the pipe and the bolts 150 15 are passed through the holes 151 and tightened so that the opposing plates clamp an intermediate portion of the folded pipe to a more flattened condition to reduce the width of channels 86, 87 and 89 at the end of the folded tube. It should be noted that the width of the clamping plate 20 145 and 14 6 is substantially smaller than the entire width of the folded tube 10, so that the channels 89 at the fold of the tube and 86 at the end of the long branch of the tube are not completely closed by applying clamping force to the folded tube. . Thus, when squeezed, fluid can still pass completely through the clamped end of the pipe, however, the ducts are so narrow that an internal pressure can be built up in the folded pipe for expansion and rounding of the pipe.

The described end heater is also useful for other, for the purposes described.

An altered embodiment of the end clip 144 is a releasable end clip 250 of the one shown in FIG. 39-41.

28 DK 174554 B1

The clip 144 has the disadvantage that it cannot be removed from the front end of the tube 10 when inserted in a blind in conduit without cutting off the clamped end of the conduit using a special remote controlled cutting tool 5 as shown in Figs. 22 and 23 and further described below.

The releasable clamping end 250, on the other hand, can be released by remote control from the clamped end of the new tube if desired and pulled out of the existing conduit by a cable.

10

The releasable clamp 250 comprises an upper jaw 250 pivotally hinged at 254 to a lower jaw 256. The lower jaw 256 comprises a front end projection 258 with a pull cable hole 260 for attaching a pull cable 262.

The jaws 252 and 256 have gripping ends 263 and 264, respectively, for gripping and compressing the front end portion 266 of the folded plastic tube 10 when heated and flexed.

A bolt 268 extends through a wide aperture 270 larger than the bolt head 269 and through a confluent smaller bolt hole 272 in the lower jaw 256. The bolt hole 272 is smaller than the bolt nut 273 and the head 269. A fork-joint releasable wedge piece 276 has parallel branches 25 277 and 278 defining an intermediate slot 280 and connected to a vertical wedge-shaped body 282 to which a releasable flexible cable 284 is secured by passing the cable through a wedge hole 286. The wedge piece 276 is intended for wedging between the bolt head 269 and 30, the upper surface of the upper jaw 252 at the arms 277 and 278 below the bolt head 269 and the slot 280 receiving the bolt shaft. Hereby the bolt head 269 is drawn against the arms 277 and 278 instead of through the wide opening 270 of the upper jaw 252 as the bolt 268 is tightened to clamp the jaw ends 263 and 264 against the tube 10.

To release the clamp 250 from the new pipe after it is retracted into the existing sewer line using the pull cable 262, and after the new pipe has been wound up except by the clamped pipe, a release cable 284. Pull the wedge piece 276 away from the bolt head 269 (or the nut 10 273 if the nut nut of the bolt is above the upper jaw 252) so that the bolt head 269 may fall down through the wide opening 270 of the upper jaw 252 to open the jaws and thereby release the pipe end. The wedge piece 276 and the clamp 250 can be pulled away from the plug wire or the main wire by their pull cables 284 and 262 respectively.

Another tool for pulling the new collapsed plug lead into the existing plug lead from the inlet opening 78 is designed as the one shown in FIG. 14-16, "seeds" 20 152 comprising a cable disc wheel 154 mounted rotatably in a disc housing 156 on a shaft 157. At the opposite sides of the open rear end of the disc housing 156, a pair of angularly bent arms 158. Each arm comprises a front arm portion 158a and an associated rear arm portion 158b, from which extends a pair of flexible steel bands 260 with inwardly curved rear ends 161. The arms 158 are hinged to the housing 156 and spring biased to bias the arms outwardly as shown. in FIG. 14. However, the arms can be turned inwardly to those of FIG. 15 when the arms and the entire structure are to be passed through the plug line.

30 DK 174554 B1

A pair of substantially triangular arms 164 are hinged to the connection points between arm portions 158a and 158b by spring biased hinge connections 166 which bias the arms 164 to theirs in FIG. 14 extends perpendicular to the arm portions 158b. However, the arms 164 can be turned in against the spring pressure of theirs in FIG. 15 when the structure has to travel through the plug line to the point of use. A pulling cable 168, both ends of which are led back to the inlet opening 98, is guided around the disc 154.

In this state, the "frog" 152 is inserted into the existing plug line and pushed through it by means of a (fiberglass flexible pressure rod) (not shown). As it reaches 15 to the intersection of the connector line and the main line with the housing 156 and the disc 154 as well as the front arm portions 158a located in the main line, the arms 164 extend outwardly from theirs in FIG. 15 to their positions shown in FIG. 14, the rear arm portions 20 158b and the bands 160 connected thereto press against the inner wall of the existing plug line. Here, a pull is applied at both ends of the pull cable 168 to anchor the "frog" 152 at the intersection of the plug lead and the main lead.

25

While continuing to apply tension to the traction cable 168, one end of the traction cable is attached to the terminal 144 (Figs. 12-13) or the releasable end clamp 250 (Figs. 39-41}. The other end of the cable, which is still at the access opening 98, is drawn to pull the heated folded plastic tube 10 through the plug conduit and around its bend 100 until the forward end of the tube 10 reaches the intersection of the plug conduit and the main conduit at the "frog" 152, the pulling force on the cable 168 can be provided. manually or using a winch 170 (Fig. 7) at the inlet opening 98. As a result of the triangular profile of the arms 164, the traction exerted on the cable 168 prevents the "seed" from moving upwards or downwards.

After the new folded plastic tube has reached the "frog" in the main conduit, the cable connection to the tube-clamp is released and one end of the cable is pulled through the disc, whereby the "frog" falls into the main flue. Then, the cable is pulled from the plug line through the inlet opening and the "seed" can be re-collected from the main line at a later time by conventional pickup technique. Thereafter, the folded plastic tube 10 is fully inserted into the plug line to be repaired, with its sun-clamped front end at the main line, and it is now ready to be reheated and expanded to a rounded profile in the existing plug line.

20

The method and apparatus for releasing the pulling cable 168 from the end clamp 144 so that the cable can be pulled through the "seed" 152 can be provided, for example, as shown in FIG. 34 and 35.

25 In FIG. 34, a slack end 168a of the pulling cable 168 is attached to a slightly ruptured cable 172 which is again secured by adhesive tape 173 to a front portion of the folding tube 10 to be inserted into the existing plug line.

From the slack end of the cable 168, in the form of loose loops 168b and 168c, it is applied through the cable hole 148 in the end clamp 144 and thence through the "seed" disc 154. The cable end of the cable remains at the access opening 98 to the plug line. If no end clamp is used, the cable hole 148 can be drilled directly through the folded front end of the plastic tube. During play 140 of pulling the cable through the "frog" to unwind the folded new tube in the existing connector, cable 172 maintains a moderate voltage at the cable end 168a. When the front end of the folded new tube reaches the "frog", the pulling end of the cable is severely shaken to rupture the cable 172 and release the slack end 168a of the cable 10 through the cable hole 148 so that the cable can be retracted.

In the embodiment of FIG. 35, the pull cable 168 is passed through the existing plug line SO to the 15 "frog" and back to the input port. Here, the blanking portion 168a of the cable must be longer than the new tube 10 to be inserted. While pulling the new tube into the existing plug line, a moderate voltage is maintained at the slack end to retract the folded new tube into the 20 plug line. When the new tube is properly inserted into the existing plug line, the slack end 168a of the cable is released at the entrance opening 98 so that it can be pulled free from the front end of the newly inserted tube through the cable opening of the terminal in ησ 148.

25 When the folded new pipe is in place in the existing plug line, it is ready to replace the existing plug line as a functioning new plug line. At this point, the front end of the folded new tube 10 is already narrowed by an end clamp 144 or 250 so that the folded tube can be applied internally via a fluid and yet allow hot steam or other fluid to pass through it. This allows the entire length of the inner tube of the folded tube to be heated to a flexible state for expansion. At this point, of course, the rear end of the newly inserted folder tube is of course also encapsulated to allow the introduction of hot steam or other fluid into the tube for heating and expansion. Such an enclosure member or plug is shown in FIG. 17-21.

A substantially tapered plug 176, referred to as a "torpedo plug," comprises a substantially tapered front portion 178 with an aperture 180 at the front end. The tapered portion 178 extends rearwardly to a short cylindrical portion 182 which is covered by a rear end plate 1S4. The plate 184 has an inlet port 186 and a hose connection 188 for connection to an inlet hose for steam or hot water so that a hot fluid under pressure can be introduced into the interior of the folded tube. Other hose connections may also be provided through the end plate 184, such as an air hose connection, for expansion of the tube by air pressure or by maintaining air pressure in the expanded tube during its curing in the expanded rounded state of the tube.

When the rear end of the folded pipe 10 has been heated, for example by means of the above-mentioned end heater 25 152, and is made flexible, the conical portion 178 of the torpedo plug 178 is driven into the pipe end as shown in FIG. 19 until the end cap 184 comes into contact with the tube end for expansion and rounding thereof corresponding to the outer diameter of the cylindrical plug portion 182. An adjustable chain-clamp 190 is used to clamp the expanded end portion of the tube to the cylindrical plug portion 182 for the sealing of the tube. .

34 DK 174554 B1

As shown in FIG. 20 and 21, the chain clamping bracket 190 comprises a clamping plate 192 with a curved tube-enclosing surface 193. On the outer convex surface of the plate 192 there is a forked bracket 194, between whose branches a nut 195 can pivot. The nut 195 takes up a threaded rod 196 with a twisting end 197, A clamping chain 198 is connected to the opposite end of the rod 196. The chain 198 may be a transmission chain or bicycle chain arranged for adjustable connection with an anchor pin 199 on the outer surface of the plate.

The clamp plate 192 is placed on the rounded tube with the inserted plug 176 and the chain 198 is wrapped around the cylindrical tube manually as tightly as possible and anchored 15 on the pin 199. Then, a clamping pressure is applied by rotating the threaded rod 196 in the shortening direction of the chain 198 a wrench via rod end 197. It is essential that the clamp be easily clamped because the plastic tube seeks to deform by heating and the clamp should be able to be clamped in place during the heating and rounding of the new tube.

Then, a steam hose is connected to the plug connection 188 and hot steam is pressed through the entire length of the folded tube 25, more specifically through the small channels along the tube, to heat the entire tube length. At the same time, the one-clamp effect on the folded tube may allow to provide an internal pressure in the tube of up to approx. 172 kPa. During the heating and pressure setting of the pipe, it expands and is rounded to a cylindrical shape over its entire length, except at the clamped pipe portion.

DK 174554 B1

After the new tube is expanded and wound to the desired dimension, usually against the inner wall of the existing plug conduit, the plastic tube is allowed to cool while maintaining the internal pressure by introducing, for example, 5 air under pressure to stabilize the new tube in a rounded shape. Then the chain clamp is released from the rear end of the pipe and the torpedo plug is removed.

In the next working step, the end clamp bracket and the still folded and squeezed rear end portion of the tube 10 must be removed from the remaining rounded portion of the tube. This is done by cutting the folded front end of the tube from the expanded and rounded tube as shown in FIG. 22 and 23.

The cutting means comprises a mechanically driven cutting tool 200 comprising a small electric motor or air motor 202 with a large orbital number located in a cylindrical motor housing 204 having a substantially smaller diameter than the inner diameter of the rounded plastic tube 10. A flexible 20 air hose or electric conductor 206 supplies driving force to the motor 202 from an outside source at the inlet opening to the existing plug line. On the drive shaft 208 of the motor, a rotor 210 is mounted with a pair of knife blades 212 and 213 pivotally mounted around pivot pins 214 at the outer ends of the rotor.

Motor housing 204 is arranged in an inflatable cage sleeve 216 which in expanded condition centers and anchors the cutting unit in place in the rounded plastic tube. A flexible 30 air supply hose 218 supplies pressurized air to inflate the sleeve 216.

36 DK 174554 B1

The knife blades 212 and 213 shown are made of steel, but they can also be made of chains or cables, and are adapted to extend outwardly under the centrifugal force produced by the rotation of the rotor 210 to tear and cut the plastic tube 10.

In use, the cutting unit 200 is pushed down through the new plastic tube 10 after it has been inserted and rounded. The impression can be made by means of a flexible fiberglass rod and with slackened cautery sleeve 216. The cutting unit 200 is pushed through the existing plug line until it reaches the clamped front end of the pipe. At this point, the bush 216 is inflated to anchor and center the cutting unit 200 in the rounded plastic tube 10, the motor 202 is actuated via the hose or conductor 206, and the motor rotates the rotor 210 to actuate the blade blades 212 and 213 until they cut off the clamped and folded plastic tube end. The cut end falls into the main conduit and can be reinvented later in conventional manner.

After cutting the front end of the pipe, the pressure in the sleeve 216 is relieved and the cutting unit 200 is removed from the rounded plastic pipe by simply pulling the air hose 218 and in the conductor 206 from the new pipe's inlet end. The new power cord is now placed in the existing power cord, and after being connected to the portion of the power cord leading up into building 96 (Figure 7), it is ready for use.

FIG. 33 shows another method for pulling the folded plastic tube 10 through an inlet opening 98a through an existing connector line 90a which cuts a tube head line 94a at an intersection 92a. At some distance from the intersection 92a, the main conduit 94a has a sewer well 216 for access to the main conduit. A cable reel 218 is disposed in the sewer well 216. The front end of a pull cable 220 is inserted into the existing connector line 90a through the access opening 98a and is pushed down through the connector line to the intersection 92a by a flexible fiberglass rod, the forward end of which is provided with a gripper means for gripping the front end of the traction cable 220 10.

The forward end of the thrust bar is also curved so that when the bar reaches the intersection point 92a, the bar can be guided around the sharp corner and into the main conduit 94a. The push rod now continues to push the pulling cable 220 15 through the main line as indicated at 220a until the front end of the cable reaches the sewer well 216, the end being attached to the play 218 cable at 219. The trailing end of the pulling cable 220, which is still at the access opening 98a to the connecting line 90a, is connected to the forward end of folded tube 10 by practicing one of the previously mentioned cable release methods. After heating the new pipe, for example in the heating box 18, to make it flexible, the pipe is drawn into the existing plug line 90a by winding the cable 220 by means of the pin 218 in the sewer well 216. The pipe drawing is continued until the front of the new pipe 10 end is reached at the intersection site 92a, after which the pull cable 220 is released from the front end of the new tube by the practice of one of the previously mentioned methods. The new tube is now ready for expansion and rounding in the existing plug line 90a by practicing either the previously described rounding method or another method which will be described in more detail below with reference to FIG.

38 DK 174554 B1 25-29, and which is known by the name "inflatable prop" method.

Here, as shown in FIG. 25 and 26, an inflatable plug 222 in place of end clamp 144 (Figs. 12-13) or end clamp 250 (Figs. 39-41) to close or narrow the inaccessible forward end of the new plastic tube so that the tube can be pressurized. , rounded up and expanded. The plug 222 is designed to withstand 10 air pressures of at least 172 kPa and expand to an outer diameter the size of the inner diameter of the curved new tube, but not to burst if it is not enclosed by the new tube. The plug 222 is also adapted to withstand a temperature greater than 93 15

The inflatable plug could well be made of a single layer of a flexible material, if such was found to meet the requirements mentioned, but such a suitable material has not been found so far. Therefore, for the time being, a two-layer structure of the plug is used. Here, the stopper comprises a canvas outer tube 224 or other textile product which is folded, closed and seamed at its front end 225. The outer tube 224 has an expanded diameter corresponding to the desired inner diameter of the new tube after rounding. The rear end 226 of the textile tube 224 remains open. An expandable inner tube or bladder 228 of cautiously ill is placed within the textile tube 224. The total length of the plug 222 may vary from about 1 to about 2 inches. 0.3 m to 6 m, depending on the application. The rear ends of the tubes 224 and 228 are contracted around a pipe nipple 230 with an air hose connection 232 to an inlet hose 234 for air or steam for supplying a fluid under pressure to the interior of the tube 228. The two tubes 224 and 228 are clamped around the tube nipple 230 by a clamp 236 to prevent leakage of pressure fluid from the inner tube 228.

5 The described inflatable plug 222 is typically used for insertion and rounding of new plug wires, whereby the previously mentioned end clamps and end cutting devices will be avoided. A typical use of the inflatable plug 222 is as follows: 10

The required stretch of folded plastic pipe for an existing plug pipe is heated and rounded at the workshop using, for example, the steam pipe previously described. The pressure hose 234 is inserted through the stretch of the rounded plastic tube attached to the inflatable plug 222 until the plug is positioned at the front end portion of the rounded plastic tube.

At this point, the pre-cut length 20 of curved plastic tube is reheated and refolded with a closed plug and the connected air hose folded inside for on-site use. FIG. 27 shows the introduction of the air hose and the associated pressure quenched plug 222 into the rounded plastic tube 10. FIG. 28 shows the refolding of the pipe 10 25 with the pressure quenched plug 222 and the hose 234 within the folded pipe.

At the point of use, the plastic tube is heated and inserted into the folded and flexible state in the plug line to be repaired. When the tube is fully inserted, the folded tube is heated with a still extinguished plug by passing steam through the tube. When the entire stretch of the inserted plastic tube has been heated, the plug 222 is inflated by means of air 40, the hose 234 for expanding the plug and thus of it | still the front end portion j of hot and flexible plastic tubing around the plug to completely plug it. After inflating the plug, for example, by means of compressed air, upstream of the plug pressure is applied to the plastic tube which is rounded and expanded, by supplying air through a hose 237 to the plug 176 at the rear end of the new pipe at the inlet opening 98.

10 After the new plastic tube has been fully coiled and expanded to the desired diameter in the existing plug line 90 and then cooled, the pressure in the plug 222 which is withdrawn from the tube 10 by the plug air hose 234. is extinguished. 15 plastic sockets are now ready for use.

FIG. 30-32 show other uses of the above-mentioned inflatable plug 222.

20 In FIG. 30, the inflatable plug 222 and its air hose are inserted into a pre-formed plastic tube 10 and folded into the tube as before, but with the plug positioned approx. 15 cm from the front end 238 of the pipe so that it can be folded as tightly as possible for easy insertion into the existing plug line. The folded tube 10 with the pressure-extinguished plug 222 located in the tube is inserted in the folded state as before in the existing plug line. The rear end of the new pipe is plugged by means of a torpedo plug 176 with the air hose 234 extending through a gasket 30 in the torpedo plug.

With the plug 222 in the off state, the folded pipe is steamed internally along the entire length of the pipe to make it foldable. When the air hose 234 protrudes from the torpedo plug 176 it is tightened and a clamp 240 is placed on the hose approx. 30 cm behind the rear end of the torpedo plug. When the folded new pipe has been heated, the inflatable plug 222 is inflated, and furthermore, compressed air is injected via the air hose 237 between the inflated plug 222 and the torpedo plug 27 6. This pressure in the new pipe will slide the inflated plug 222 forward towards it. the front end 238 of new pipes until the plug 10 is stopped when the clamp 240 hits against the rear end of the torpedo plug 176. At this point, the front end of the new tube, like the rest of the tube, will be completely rounded. Thereafter, the pressure in the plug 222 is quenched and it is withdrawn from the tube just inserted.

15 In FIG. 32, the new tube is inserted into the existing plug line in the folded state using one of the methods described above and without a clamp on the front end of the tube or an inflatable plug to close or 20 narrow the front or downstream end of the tube. However, at least approx. 25 cm extra length of the folded plastic tube at the inlet end of the existing plug line. The folded pipe is steam heated internally to make it pliable along the entire length of the pipe. In the hot state, an external clamp 242 is placed on the folded tube approx.

3 m downstream of the torpedo plug 176. Then the plastic pipe stretch of approx. 3 m between the clamp and the torpedo plug by injecting steam from line 237 through the torpedo plug into the upper 3 m of the folded pipe, which is then cooled to its rounded state.

'42 DK 174554 B1

Thereafter, the torpedo plug 176 is removed and the inflatable plug 222 is inserted in at least partially inflated condition for easy insertion into the new tube's rounded cross-sectional profile. The torpedo plug 176 is reinserted at the end 5 of the rounded section of the new tube with the air hose 234 from the inflatable plug 222 extending through the plug 176. Now the clamp 242 is removed from the new tube and the pressure is quenched in the inflatable plug 222. The new tube is reheated internally with steam along the entire length of the pipe to make it pliable. When the new pipe is hot, the pressure is partially increased in the inflatable plug 222. The internal pressure of the new pipe, caused by steam or air, is increased and the partially inflated plug 222 is propelled through the new pipe, which at this point is partly unfolded and partly rounded. When the inflatable plug 222 reaches the front or downstream end of the new tube, it is fully inflated to be able to plug the end. The new tube is now supplied with fluid under pressure, fully rounded and cooled and thereby stabilized in an upright state. When the new pipe is cured, the pressure in the inflated plug 222 is released, which is pulled out from the fully rounded pipe.

The invention also provides a method and apparatus for sealing the gap between the new rounded pipe and the existing pipeline, where such pipes intersect another opening, either a well or another conduit. A typical pipe intersection will be at the downstream end of a building sewer line where it enters a sewer main line.

The sealing closure is a simple compressible rubber socket that encloses the intersecting end of the folded new tube. The thickness of the bush is typically 3-6 rooms and its length is typically 30-60 cm.

When the front end of the folded new tube is inserted and extensible, such as at a well, the bushing can be pushed over the folded end of the new tube before rounding. During the rounding of the pipe end, the bushing is also rounded. The new tube is expanded during the rounding process until the rubber socket is tightly compressed between the new tube 10 and the existing tube to establish the fluid-tight closure. For the closure of the remote and inaccessible downstream ends of building sewer plugs, another method is employed using an adhesive reinforced rubber socket. The front end of the folded new pipe 15 is heated, unfolded and rounded before insertion into the existing pipeline. The adhesive-reinforced sleeve is applied to the rounded tube which is retracted with the sealed sleeve. Then, the folded new tube is introduced into the existing pipeline by the practice of one of the methods mentioned above.

The preferred method of rounding and expanding the distal end of the tube to be closed is the use of the aforementioned expandable plug.

With such a plug, the expansion and thus the closure becomes more complete and safer than with the other methods mentioned.

As previously mentioned, a preparation of the thermoplastic tube 10 in the embodiment of FIG. 8. Once cooled and cured in the folded state, the tube retains a tendency to recapture the particular shape to which the tube seeks to return at any time it is reheated and not prevented therein.

This shape retention tendency of the tube in the folded state can advantageously be used to remove a damaged section of such a tube from an existing underground pipe.

When the damaged thermoplastic pipe is to be removed from the inside of an existing pipe, the pipe is heated by passing fresh steam through the pipe and, if possible, along the outside of the pipe 10. In heated condition, the damaged pipe section will collapse to its original folded shape. This collation and refolding can be accelerated by connecting a vacuum pump to the inner tube to lower the internal pressure in the tube. In collapsed and folded condition, the hot plastic pipe can be pulled away from the existing pipeline by means of a cable play with the tow cable attached to an accessible end of the collapsed pipe.

It is important to heat the folded thermoplastic tube 20 for easy insertion, especially when consideration is given to bends in the existing pipeline or when the new tube is to be passed down through a narrow and deep vertical hole. Several methods of heating for introduction are described above using a heat box or a long steam tube. Another method is to heat the inside of the existing pipeline into which the thermoplastic tube is to be inserted.

According to this method, a short pipe section connected to a steam source is connected to the rear end of the existing pipeline to be repaired. A cover of textile at the rear end of the steam pipe section is wound around the folded new pipe during insertion through the steam pipe joint and into the existing pipe 45 DK 174554 B1 for heating the new pipe during insertion. This method can also be used advantageously in connection with the other heating methods described.

5 The embodiment of FIG. The flattened folded shape of the rigid thermoplastic tube shown in Figures 3 and 8 is also significant because this profile gives the tube certain properties that cannot be achieved with other tubes which are only partially or completely collapsed to reduce their total cross-sectional diameter for insertion into the an existing pipeline:

First, the folded shape shown in heated and flexible condition can be conveniently and compactly stored for long or short lengths on a coil. The coil can again be used for storing, reheating and feeding the pipe in a pipeline.

Second, the particular design can be introduced into a pipeline around a sharp bend from a narrow vertical inlet port, such as a well, and can be inserted around sharp bends into the existing pipeline itself. For example, a rigid PVC pipe having a typical thickness-to-thickness ratio within the previously mentioned area, when flattened and folded to that of FIG. 3 or 8, 25 and heated to a flexible state, exhibit a ratio of the minimum bending radius to the rounded outer diameter of between 1 and 2, i.e., a typical rigid PVC pipe of 10 cm diameter in the embodiment shown in FIG. 3 or 8 can handle a curve with a radius of 30 between 10 cm and 20 cm, depending on the wall thickness, without damaging the pipe walls. Such a small bending radius is unattainable with the conventional known designs of rigid thermoplastic tubes in their flexible state.

in 46 DK 174554 B1

Third, in FIG. 3 and 8, notwithstanding the advantages mentioned above in the heated and flexible condition, are readily reshaped into a rounded profile and hardened to render the tube structurally rigid and sufficiently strong to withstand external soil pressure and water pressure.

Thus, the inserted thermoplastic tube according to the invention is not merely a casing for a damaged existing pipeline, but a real replacement tube.

Claims (34)

A hose piece of a thermoplastic resin material for insertion into and lining of an existing pipe string, characterized by:; the hose piece assumes a diminished, non-circular shape, 10 that the hose piece is rigid at ambient temperatures and relatively thick-walled, so that it can withstand external pressure, that the hose piece is flexible at a predetermined high temperature, that all of the hose pieces cross-section dimensions are smaller! than the diameter of the hose piece after the hose piece is heated and brought to assume a tubular shape, and 20 that the hose piece has a memory to maintain the diminished non-circular shape when the hose piece is made flexible by heating to the high temperature. Hose piece according to claim 1, characterized in that the hose piece is made of polyvinyl chloride i. (PVC). Hose piece according to claim 1, characterized in that the hose piece in the reduced form has a flat 30 and longitudinally folded shape comprising a first and a second branch connected by a round bead-shaped elongated fold part. DK 174554 B1 4 8 Hose piece according to claim 3, characterized in that the first and second branches of the folded hose piece are terminated with rounded bead-shaped free ends defining fluid channels along the length of the folded hose piece. Hose piece according to claim 4, characterized in that one branch is longer than the other, so that the beaded end of the shorter branch rests behind and on the beaded end of the longer branch to minimize the total thickness of the folded hose piece. A hose piece according to claim 5, characterized in that it is wound on a bearing coil. 15 A method of making a thermoplastic hose piece, which hose piece is intended to be inserted into a desired non-circular collapsed and folded mold into an existing tube string to feed it, characterized in that the thermoplastic material is extruded through a nozzle to molding the plastic material into a tubular shape of the desired size, forming the extruded tubular material from the die at a temperature above the temperature at which the material can bend to the desired non-circular collapsed and folded shape, and extruded material is cooled in its non-circular collapsed form after shaping, whereby the hose piece has a memory for the desired non-circular collapsed and folded shape so that the hose piece, when heated to make it flexible, retains the desired non-circular shape. collapsed and folded shape. Method according to claim 7, characterized in that the cooled hose piece is reheated in the non-circular collapsed and folded form to make the hose piece flexible in a longitudinal direction so that it can be assumed to take a suitable shape for storage. . Method according to the preceding claim, characterized in that the hose piece is wound on a bearing coil in the non-circular collapsed and folded form, being withdrawn from the reheating step. Method according to claim 7, characterized in that the hose piece is reheated by passing the hose piece through a heating chamber. 20 Process according to claim 10, characterized in that the heating is carried out by supplying steam to the heating chamber. A method according to claim 7, characterized in that the shaping includes passing the extruded thermoplastic material through a non-circular orifice calibrator to impart the size and shape of the extruded thermoplastic material to the desired non-circular and folded shape. DK 174554 B1 Process according to claim 12, characterized in that the thermoplastic material is subjected to a partial vacuum in the calibrator. Method according to claim 12, characterized in that the shaped hose piece is removed from the calibrator in the desired non-circular collapsed and folded shape by applying a pull. Method according to claim 7, characterized in that during the provision of the non-circular collapsed and folded form, longitudinal inner passages are formed along the hose piece, in addition injecting liquid under pressure into the interior of the thermoplastic material during shaping. Process according to claim 7, characterized in that the plastic material is formed by flattening and folding the tubular shape longitudinally. 20 Process according to claim 7, characterized in that the plastic material is formed by flattening the tubular shape and folding longitudinally to form a short branch and a long branch and a rounded fold part. 25 Method according to claim 7, characterized in that the cooled thermoplastic material is reheated in the flattened and folded form to make it flexible longitudinally so that it can be assumed to take a suitable shape for storage. DK 174554 B1 Process according to claim 18, characterized in that the thermoplastic material is wound on a bearing coil. Process according to claim 7, characterized in that the thermoplastic material is PVC. 21. Apparatus for making a piece of one in the main! the case rigid thermoplastic hose having a diminished flat and 10 folded shape intended to be inserted into an existing pipe string to carry it, all the cross-sectional dimensions of the hose piece in the diminished shape being smaller than the diameter of the hose piece assuming a tubular shape; characterized by: an extrusion means for extruding a length of a thermoplastic material having a substantially hollow tubular cross-section, and 20 forming means by vacuum to bring the extruded thermoplastic material from the tubular mold to assume the desired reduced flattened and folded shape, wherein all dimensions are smaller than in the tubular form, and to maintain this diminished shape, 25 means for pulling the hose piece from the shaping means, and reeling means for spooling the hose piece in the diminished flattened and folded state, whereby the hose piece retains its diminished shape subsequently reheated f or to make the hose piece pliable. DK 174554 B1 Apparatus according to the preceding claim, characterized in that the calibrator means comprise calibrator plates with mutually arranged openings 5 for shaping the extruded material to the desired shape. Apparatus according to the preceding claim, characterized in that the openings in each calibrator plate 10 have a short branch and a long branch and an intermediate rounded fold part. Apparatus according to claim 21, characterized in that it further comprises pressure means for holding the shape of the extruded material in the calibrator means. Apparatus according to the preceding claim, characterized in that the pressure means applies a partial vacuum on the outside of the extruded hose piece. 20 Apparatus according to claim 24, characterized in that the pressure means is a source of pressure fluid injected into the internal passages of the extruded tubing. 25 Apparatus according to claim 21, characterized by cooling means for cooling the hose piece. Apparatus according to claim 21, characterized in that the pulling means comprise rollers. ! Apparatus according to claim 27, characterized by reheating means for reheating the cooled hose piece in the diminished flattened and folded form after removal from the cooling means to make the hose piece flexible to make it suitable for storage. Apparatus according to the preceding claim, characterized in that the reheating means comprise a steam chamber. Apparatus according to claim 29, characterized by 10 means for storing the reheated tubing in a layered relationship. Apparatus according to claim 29, characterized by rewinding means for rewinding the flexible material 15. reduced form. A method of repairing an existing main pipeline section having at least one side branch pipe, characterized in that a piece of a substantially rigid thermoplastic casing tube is inserted from one end of the main pipeline section to be repaired. a diminished shape and whose cross-sectional dimensions are less than that of the main pipe until the hose piece is at least coincident with the length of the main pipeline section to be repaired, that the hose piece is heated to a temperature where a rounded shape can be provided, while the hose piece is hot and malleable, an internal fluid pressure is applied to the hose piece to expand it so that it assumes a rounded shape within the main pipeline section, and by continuing to apply said fluid pressure to the hose piece while hot and malleable, to extend the hose piece so that it is close to the main pipeline section, and to cause the hose piece to bulge into the side branch tube by the side branch tube to allow an exact location of the side branch tube 10 from the interior of the tube section. A method according to the preceding claim, characterized in that the exact position of the side branch tube occurs by observing the location of the bulge with a television camera passing through the tube section and by cutting an opening into the side branch tube at the tube section. cutting off the bulge using a remote controlled cutting means 1 operating within the hose piece. 20 The method according to claim 33, characterized in net, the hose piece is manufactured in a flattened and longitudinally folded form. The method according to claim 34, characterized in that the hose piece is made of PVC.