KR970005450B1 - Apparatus and method of removal of replacement pipe - Google Patents

Abstract

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Description

Installation method, installation device, and removal method of the replacement pipe

1 is a cross sectional view of a conventional thermoplastic pipe, such as a PVC pipe, used according to the invention in its expanded state.

FIG. 2 is a perspective view of the thermoplastic pipe of FIG. 1 and the device for shrinking the pipe in a rounded, collapsed and folded state for storage in a spool.

A cross-sectional view of a folded thermoplastic pipe taken along lines 3-3 of FIGS. 3 and 2.

FIG. 4 is a schematic diagram showing a process of installing the folded and wound thermoplastic pipes of FIGS. 2 and 3 from a manhole into a sewage main body, and reheating the thermoplastic pipes in a roll to install them in an underground pipe to be repaired.

FIG. 5 is a schematic cross sectional view of the main portion of the apparatus for inserting the folded thermoplastic pipes of FIGS. 2 and 3 into an existing main pipeline as shown in FIG. 4 and then inflating and rounding them.

6 is a schematic cross-sectional view showing another structure in which a folded thermoplastic pipe is inserted into an existing conduit and then expanded and rounded.

7 is a schematic cross-sectional view of a typical building sewer pipe extending from a building to a main sewer pipe, illustrating a method of installing a thermoplastic pipe in an existing building sewer pipe in accordance with the present invention.

8 is a cross-sectional view of a preferred form of the thermoplastic pipe of FIG. 1 folded for installation in an existing underground conduit.

9 is a schematic elevation view of an apparatus for manufacturing the thermoplastic pipe of FIG. 1 in a folded form as shown in FIG.

FIG. 10 is an enlarged elevation view of the compensator of the apparatus of FIG. 9 for use in making thermoplastic pipes in the form shown in FIG.

FIG. 11 is a front view of a single correction plate of the compensator of FIG. 10 as seen from line 11-11 of FIG.

FIG. 12 is a plan view of the folded end of the thermoplastic pipe of FIG. 8 with an end clamping device attached to it for use in pushing the pipe into an existing conduit and for constraining the pipe end to pressurize the inside thereof to expand the pipe.

13 is a cross-sectional view taken along the 13-13 line of FIG.

FIG. 14 is a partial schematic plan view of the cable pulley device shown in FIG. 7 in an operating position, used to pull the folded thermoplastic pipe of FIG. 8 into an incoming lateral sewer. FIG.

FIG. 15 is similar to FIG. 14 but with a top view of the device in a folded state for insertion into an incoming lateral sewer.

16 is a partial schematic side view of the device of FIGS. 14 and 15.

FIG. 17 is a side view of a plug mechanism (tool) used to block the end after the longitudinal end of the thermoplastic pipe shown in FIG. 8 is rounded to transfer fluid, heat and fluid pressure into the interior of the thermoplastic pipe .

18 is a front view of the inlet end of the FIG. 17 mechanism.

19 is an elevational view of the thermoplastic pipe end with the plug mechanisms of FIGS. 17 and 18 inserted into the pipe and clamped in place by the chain clamping device.

FIG. 20 is a side view of the chain clamping device of FIG. 19 showing a state before being installed in the pipe and plug of FIG. 19; FIG.

FIG. 21 is a cross sectional view taken along line 21-21 of FIG. 19 showing a state in which the chain clamping device of FIGS. 19 and 20 clamps the thermoplastic pipe end to the plug mechanism of FIGS. 17-19.

FIG. 22 shows the end clamps (clamping device) of FIGS. 12 and 13 installed at the pipe end and the insert inserted inside the round pipe for cutting the clamped end from the rest of the rounded pipe and the rest of the pipe. Some schematic longitudinal cross-sectional view showing the introduction end of the thermoplastic pipe of FIG. 8 with a cutting mechanism according to it.

FIG. 23 is a sectional view of the 22nd pipe and the cutting tool taken along the line 23-23 of FIG.

FIG. 24 shows a state in which a heater (heating) mechanism is installed at the folded end of the thermoplastic pipe of FIG. 8, and is a partial schematic side view of the end heater device used to heat the end for reworking the end of the thermoplastic pipe.

FIG. 25 is a view of the swellable (expandable) end plug mechanism used to block or limit the ends of the thermoplastic pipes instead of the end clamping means of FIGS. 12 and 13 so as to expand and round the folded thermoplastic pipe. Perspective view.

FIG. 26 is a reduced side view showing in cross section a portion of the inflatable pipe of FIG. 25; FIG.

FIG. 27 is a schematic diagram illustrating the installation of the expandable plug mechanisms of FIGS. 25 and 26 in a thermoplastic pipe in an expanded and rounded state.

FIG. 28 is a schematic diagram showing the pipe of FIG. 27 after being folded back with an inflatable plug similar to that of FIG. 27 but in an inflated state.

FIG. 29 is a schematic diagram illustrating the use of the inflatable plug mechanism of FIGS. 25 and 26 during installation of the thermoplastic pipe in the incoming lateral sewer pipe.

30 is a schematic diagram illustrating another method of use of the inflatable plug mechanism of FIGS. 25 and 26.

FIG. 31 is a schematic diagram illustrating the use of the inflatable plug mechanism of FIGS. 25 and 26 according to the method illustrated in FIG. 30.

FIG. 32 is a schematic diagram illustrating another example of using the inflatable plug mechanisms of FIGS. 25 and 26 to insert a folded thermoplastic pipe into an existing underground conduit and then expand and round the pipe.

FIG. 33 is a schematic diagram of a main pipeline section and cross-entry lateral pipeline illustrating another method of pulling the thermoplastic pipe of FIG. 8 into an incoming side tube to be repaired. FIG.

FIG. 34 is a schematic view of the end of the folded thermoplastic pipe of FIG. 8 illustrating one method of releasing the traction cable from the leading end of the pipe after inserting the pipe into the underground conduit.

FIG. 35 is the same schematic view as in FIG. 34 illustrating another method of releasing a rigid cable from the thermoplastic pipe after inserting the thermoplastic pipe into the underground conduit.

FIG. 36 illustrates a method of forming and cutting openings through newly installed thermoplastic pipes for reopening between an incoming lateral pipeline and a main pipeline, wherein the thermoplastic pipe of FIG. 8 is installed and installed in the main pipeline to be repaired. Sectional view of the intersection of the main and incoming side pipelines after expansion.

FIG. 37 is a schematic side view illustrating a method and apparatus for folding a round manufactured thermoplastic pipe for insertion into an existing underground conduit. FIG.

38a-e are schematic cross-sectional views taken along lines 38a-38a through 38e-38e of FIG. 37, respectively.

FIG. 39 is a schematic side view of part of a releasable end clamp (clamping device), attached traction cable and release line for use in clamping the leading end of the pipe during installation of the folded pipe of FIG.

40 is a top view of the end clamp of FIG. 39;

FIG. 41 is a plan view of the release wedge of the end clamp of FIG. 39; FIG.

* Explanation of symbols for main parts of the drawings

10 pipe 12 spool

16: manhole 18: hot box

19: air circulation device 20: truck

21: door 22: gutter

23: roller 28: clamp device

42: pressure gauge 44: relief valve

50: mandrel 60,61: flat roller

70: main pipeline 96,88,89: passage

90: excavation 94: main building

108: vacuum box 118: die

120: pin 122,123: partition plate

130: assembly rod 137: orifice

147: nose portion 150: clamping bolt

152: End Heater

The present invention is directed to an improved method and apparatus for installing replacement pipeline portions in existing underground conduits such as pipeline sections that need to be repaired or replaced. The present invention is particularly applicable in sewer pipes of buildings intersecting with the sewer mains, in other lateral pipelines intersecting with the main pipeline, in pipeline sections including curves and bends, in other pipeline sections intersecting the sewer pipes of the building, and the like. The present invention relates to a method and an apparatus for installing a replacement pipeline part, and also to a connection with a side (side) sewer pipe that is difficult to position after installing a new pipeline part in an existing underground pipeline section.

In the prior art, by installing a flexible plastic membrane or liner in an existing pipeline at a predetermined position in the basement, or inserting a new plastic pipe into the existing pipe, it is possible to use an underground pipe such as a sewage line. Various methods and apparatus for repairing pipelines have been proposed.

As one of them, a method of lining (padding) a pipeline with a flexible plastic such as polyethylene is known. According to this method, the liner is inserted through the insertion hole at predetermined intervals along the pipeline, but it is expensive to implement this method.

As another example, according to the method as described in US Pat. Nos. 3,927,164 and 4,064,211, the flexible tube is inverted when inflated and blown into the pipeline section from one end of the pipeline section. These methods are expensive because they require special equipment, extensive heating, and expensive materials.

Since the above and most other methods use flexible or semi-flexible liners that cannot withstand any external hydrostatic or earth pressure, existing underground pipelines may be damaged at any point. If so, the liner may be retracted, for example, from an external pressure of greater than about 0.28 kg / cm 2 (about 4 pounds per inch 2), making it impossible to properly maintain.

US Pat. No. 4,394,202 to Thomas et al. And US Pat. No. 2,794,758 to Hyper et al. Also disclose a method of inserting a flexible tube into an underground pipeline as an inner surface film for the pipeline. Thomas et al. Disclose a method of attaching a flexible tube to an existing pipeline using an expandable short piece of hard plastic coated with an adhesive. However, Thomas and Harper et al. Have the same drawbacks as described above for other conventional methods using flexible membrane materials in view of the lack of hoop strength required to withstand external soil pressure and fluid pressure. Have

Alternatively, a method of inserting a rigid tube into the inner surface of the pipeline requiring repair has been proposed. For example, in British Patent Application Publication No. 2,084,686, large round rigid plastic tubes are flattened or shrunk at the work site and then inserted into an existing pipeline in a rigid state cooled through large-scale excavation in a manhole.

After insertion, the plastic tube is inflated using heat and internal pressure. The plastic tube expands toward the existing pipeline.

According to British Patent No. 1,580,438, existing underground pipes are lined by plastic liner tubes made of plastic, such as polyethylene or polylopropylene, with plastic memory. The liner tube is manufactured into a non-round U shape to fit into the existing pipe inner surface and then inserted into the existing pipe in a non-round shape, and then expanded in a round state toward the existing pipe by heat and pressure.

EPC Patent Application Publication No. 100,000,576 proposes the insertion of semi-rigid plastic tubes into the inner surface of existing pipes. It has sufficient hoop strength to withstand all or part of the external pressure applied to the semi-rigid plastic tube.

a. Repair of bent pipelines and pipelines with entrances only at one end

Most of the above and other prior art methods, such as the use of rigid or semi-rigid tubes for insertion into existing underground pipelines, have the following common drawbacks:

Because of the rigid or near-rigid nature of the tubes themselves, they should only be inserted into existing pipelines that are straight or nearly straight. This means that, for example, with respect to underground sewage lines, this conventional method is limited to use only in sewage mains, since sewage mains usually have a straight pipeline between the manholes. Most of these conventional methods are not suitable for use in the repair of many building sewer pipes extending from the sewer main building. Often such side tubes have curves or bends that cannot be passed through rigid or semi-rigid plastic pipes. In addition, since these side tubes cannot normally enter and exit the manhole at either end, there is a considerable cost in the known method of installing lining or replacement pipes that require manholes or other means of access at both ends. Most known underground replacement pipe installation methods require large-scale excavation to provide a space for insertion of straight (straight) rigid plastic replacement pipes at the ends of the side tubes to be lined or repaired. do. This large excavation at the end of the building adjacent to the sidewall or at the other end where the sidewall intersects the main building is impractical and usually expensive.

Moreover, most known existing pipeline linings or repair methods require doors at both ends of the pipeline section to be repaired. This method is not possible because the side tubes are typically formed to intersect the main building at points where they are not entered by the manhole.

For this reason, the method of lining and repairing underground pipelines cannot simply be applied to building sewer pipes.

b. Repair of sewage main building

Another drawback of using known methods of repairing and lining existing pipeline segments that intersect with building sewer lines using straight rigid or semi-rigid piping is that once the replacement piping is Once located in the section, it is very difficult to establish the exact location at which the incoming side tubes and the main pipeline intersect, in order to cut the entrance to the replacement ducts into the service laterals. This is especially true if the replacement tubing has a sufficient thickness so that its own hoop strength is sufficient to withstand typical fluid and surface pressures.

For the reasons mentioned above, repair and repair of existing underground pipeline sections, in particular, building sewer pipes, other pipeline sections with curves and curves, and pipelines that cannot be easily accessed from both ends of the pipeline section to be repaired. There is a need for improved methods, devices, and tools (tools).

Accordingly, the main object of the present invention is to provide the following.

1. It is particularly suitable for use in repairing and replacing main and intersecting building sewer lines that intersect building sewers, and provides new and improved replacement pipeline products for installation in existing underground conduits.

2. Provides a new and improved method for manufacturing repair and replacement pipeline products that is particularly suitable for installation in existing underground conduits that intersect or not extend straight to the side entry lines.

3. Provide a way to install new or replacement pipeline sections in existing underground conduits that do not intersect or extend straight to the building sewer line.

4. Provide apparatus and tools for making the replacement pipeline products described above.

5. Provide apparatus and tools for installing the aforementioned pipeline products in existing underground conduits that do not intersect or extend straight to the side entry lines.

6. Insert a new or replacement pipe in the folded state, and then reshape (reproduce) a stable round shape in the existing underground conduit, especially the building sewer pipe, to form a new or replacement thermoplastic pipe portion installed in the underground conduit. Provided are tools and tools for reforming.

The present invention is directed to a novel, improved repair and replacement pipeline product that is particularly suitable for installation in existing underground conduits, such as building sewers with bends and curves, and also for the manufacture of the pipeline product, and the existing stretched or curved A series of closely related methods, devices, and tools for installing a pipeline product in a conduit, inserting the product into an existing conduit in the folded state, and then reforming (reproducing) a round shape. The products, methods, apparatus and tools of the present invention are particularly useful when installing the product in a variety of existing underground conduits and building sewers which are crossed by side tubes, have bends or curves, or have access means only at one end of the conduit. Suitable for use on

According to one feature of the invention, the replacement pipeline product is a thermoset plastic material that is extruded and preferentially folded to form a flat shape, so that when reheated, it can maintain a folded memory and easily roll up for storage and use Cross-sectional size can be reduced to facilitate insertion into existing underground conduits, pipelines deep through the basement through manholes or cleaning holes or other small vertical holes and abrupt bends without perforation or damage to plastic materials Hot fluid can be circulated to reheat the entire length despite being folded flat.

According to another feature of the invention, the above-mentioned plastic (plastic) pipe product, for example, after reheating the plastic pipe in a flexible state, the high-temperature flexible plastic pipe is folded to the intersection of the traction cable and the side pipe and the main pipe. It is installed in an existing curved side tube by pulling from the temporarily mounted pulley equipment or the manhole closest to the main tube to the side tube by the cable sheath. It is then rounded (annular) by passing a hot fluid through the pipe in a folded state and heating it over its entire length, blocking or restricting its inlet end (tip) and injecting a pressurized fluid, such as air, to the other end under constant pressure. Reform and expand. Thereafter, the internal pressure is continuously applied to the reshaped round pipe while cooling to stabilize to a round shape.

According to another aspect of the present invention, the opening of the plastic pipe is blocked or restricted to allow the hot fluid to pass through in the folded state and to expand and reform the folded pipe in a rounded shape by applying internal fluid pressure. To provide a variety of means.

According to another feature of the invention, it provides a means for blocking or sealing the leading end of the folded pipe to pressurize the internal fluid of the folded pipe when the folded pipe is inserted into an existing underground pipeline.

According to still another aspect of the present invention, a unique pulley can be pushed through the inlet side tube to the intersection of the inlet side tube and the pipeline, and can be arbitrarily mounted at the intersection by maintaining tension at both ends of the cable; A cable device is provided. One end of the cable is fixed to the leading end of the folded pipeline to be installed, and the other end of the cable is then heated and pulled to pull the folded plastic pipe in the flexible state into the existing side pipe.

According to another feature of the invention, the plastic can be plasticized sufficiently to rework the selected part of the plastic pipe and to insert the plug or to make the entire length of the pipe sufficiently flexible to be inserted into an existing straight conduit. Various means for heating both ends and various other portions of a pipe product are provided.

The above and other objects, features, and advantages of the present invention will become apparent from the following detailed description with reference to the accompanying drawings.

Detailed Description of the Preferred Embodiments

[Repair of sewage main building]

In FIG. 1, reference numeral 10 denotes a pipe used to reinstall, repair or replace an underground pipeline section, such as a sewage pipe, in accordance with the present invention. The pipe is made of a thermoplastic material such as PVC, and especially, when exposed to the basement, it is formed of a hard thick material having sufficient hoop strength enough to withstand external soil pressure and fluid pressure. Such thermoplastic pipes also become flexible when, for example, PVC pipes are heated to a temperature of, for example, 93.3 ° C. (200 ° F.) or more. The properties of the pipe 10 are structurally rigid at typical above-ground atmospheric and underground temperatures, but they become flexible when heated or reheated and can be transformed into various forms. Another property of this thermoplastic material is that it has the following memory. In other words, if a thermoplastic material is made into a special shape such as a round tubular shape, then heated to flatten or fold, then the folded shape is cooled to stabilize and then reheated without restraint, it is returned to the original round tubular shape. . Conversely, if, for example, the pipe is initially produced in the folded form as illustrated in FIGS. 3 and 8, then heated and expanded in a rounded form under internal pressure, then cooled and stabilized in a rounded form, without restriction Subsequent reheating will return to the original folded form. The memory form of such thermoplastic pipes is advantageously used in any embodiment of the present invention.

Conventionally readily available pipes of the type usable in practicing the present invention have a standard dimensional ratio (outer diameter / wall thickness) available for underground pipelines, such as drain lines, constant lines, etc., in the range of 13-65. Polyvinyl chloride (PVC) pipe.

In the most preferred embodiment of the present invention, although the thermoplastic pipe is manufactured in a folded form as shown in FIG. 8 in the manner described for the apparatus of FIGS. 9-11, certain features of the invention are also It can of course be practiced using thermoplastic pipes made in tubular or round form. 2 illustrates an apparatus 11 for reshaping a conventional PVC pipe 10 made in a round shape. 3 illustrates the pipe cross section after reforming (shaping) by flattening and folding the pipe using the apparatus of FIG. 2. In particular, the PVC pipe is heated in a conventional manner by means of heating means 11a, such as a steam box controlled to be thermostatically controlled or a housing containing an electrical heating member controlled to be thermoregulated. By passing the original round pipe 10 through a heating box, ie the heating means 11a, the pipe is heated to a temperature sufficient to be calcined or flexible. It can then be flattened or folded by the folding device 11 to reduce its overall cross sectional size so that it can be easily pulled into an underground conduit with an inner diameter equal to or slightly larger than the original outer diameter of the thermoplastic pipe. A reduced sized thermoplastic pipe 10a is illustrated in FIG. 3.

Although the apparatus 11 of FIG. 2 schematically illustrates a pipe folding apparatus, a practical leaf folding apparatus and method will be described in more detail in connection with the apparatus of FIGS. 37 and 38a-e. Here, the heating pipe, that is, the round pipe 10 passing through the heater 11a is first flattened by a pair of opposing flat rollers 60, 61, and three different sets of folding rollers 63, 64. It is passed by the folding wheel 62 while being gradually supported by the (65). The pair of folding rollers 63 are arranged to interact with the folding wheel 62 to begin folding the pipe 10 into a U-shape. Thereafter, the three folding rollers 64 are arranged in a semi U-shape to cooperate with the folding wheel 62 to continue the folding process. Finally, the set of four folding rollers 65 is arranged in a U shape to cooperate with the folding wheel 62 to complete the process of folding the pipe 10 in a U shape. The folded pipe then passes through a surviving portion 62 that cools the pipe to a U-shape to have a U-type memory. The folded pipe from the surviving portion 66 is passed through a steam tube to be reheated and flexible to be stored to a predetermined length or inserted directly into an existing conduit.

Optionally, after the flattening process and before the folding process, the pipe may be wound in a flat state in the hot box 18 shown in FIG. The flat wound pipe can be reheated in the hot box at the shop floor, so it is folded as described previously just before it is pulled out of the hot box and inserted into the pipe to be reinstalled.

In some cases, especially if the thermoplastic pipe in a rounded state has an outer diameter smaller than the inner diameter of the pipeline to be repaired, it is possible to install the thermoplastic pipe in an existing pipe in a flat state, but in most cases, thermoplastic Preferably, the pipe is installed in an existing pipeline in a vertically folded form as shown in FIGS. 3, 8 and 38e. However, the form shown in FIG. 8 is preferable for the reason described below.

As mentioned above, thermoplastic pipes made in a rounded shape have a memory that tries to return to a rounded shape when folded and reheated. Thus, if it is necessary to reheat the folded pipe to be flexible for installation in an existing pipeline, the pipe will return to round as soon as there is no restraint. For this reason, it is preferred that the thermoplastic pipe is first manufactured in the desired folded state. Then, when the folded pipe is reheated to be flexible to be inserted into the existing pipeline, the pipe is fully inserted into the existing pipeline and remains folded until the round remodeling process is ready.

Regardless of whether the thermoplastic pipe is made round or folded, the pipe must be folded when it is ready to be inserted into existing piping. It is also preferable that the thermoplastic pipe is heated and wound so that it can bend in a storage spool such as the spool 12 shown in FIG.

The spool 12 of the folded thermoplastic pipe is stored in a housing or hot box 18 equipped with a heater 24 which is controlled to be temperature controlled to heat the interior of the hot box so that the spool 12 can be folded pipe (if desired). Make 10a) flexible. The hot box 18 is also preferably equipped with an air circulation device 19 so as to prevent stratification of heat in the hot box so that the spool of the folded pipe can be constantly heated. Hot box 18 is preferably portable and is shown in FIG. 4 in the cargo compartment of truck 20 for moving to the site. A small form of hot box can be manually moved for use when entering a pipeline that is small and difficult to access, such as building sewers, by means of wheels. In either case, powered or manually operated, means are provided for rotating the spool to wind or unwind the pipe onto the spool. The hot box 18 is equipped with a door 21, and also a trough 22 for easily inserting the folded thermoplastic pipe into the underground pipeline through a vertical entrance opening, such as the manhole 16 of the sewer main pipe 14, and The roller 23 may be mounted.

[How to repair sewage main building]

According to one embodiment of the invention, the hot box 18 is moved to an opening in the work site, such as the manhole 16 of an underground pipe, such as the sewer main pipe 14, to be repaired. One end of the reduced pipe 10a is connected to a traction line 26 made available at an adjacent opening of an existing pipeline, such as another manhole (not shown), and is clamped by a clamp means 28 to It is connected to the free end or the introduction end. The new pipe can be bent by heating the spool 12 in the hot box 18 via the heater 24. The traction line 26 is then actuated by a winch in the next manhole downstream of the manhole 16, for example, to allow the bendable folded pipe 10a from the spool 12 to the existing sewer mains 14. It is towed to the next manhole through 22 and its surrounding rollers 23. After the new pipe is inserted, it is heat expanded to be rounded or generally rounded to provide a pipe that is installed in a rigid shape with a thickness of sufficient hoop strength to resist external hydraulic and surface pressures.

5 illustrates one way to push a pipe of reduced dimensions into the original pipe to be reinstalled or replaced and then expand. According to this method, a pair of plugs 30, 32 are inserted into opposite ends when at least the ends of the folded pipe are in a state where they can be heated and bent. The plug 30 is installed at the rear end of the new pipe section at the insertion end of the existing pipeline. The plug 32 is installed at the leading end or towing end of the new pipe after disconnecting the towing line 26. Each plug 30, 32 is equipped with a detachable peripheral expansion gasket member 34 installed for releasable sealing engagement between the original pipe, ie the sewer main pipe 14 and the new pipe 10a. The gasket member 34 bulges (expands) through a pressure line 36, such as an air pressure line, which is connected to ground control means (not shown). The plug 30 has an inlet conduit 38 for introducing an expansion medium such as live steam or hot water into a new pipe. These conduits are equipped with pressure gauges 42 and relief valves 44 as well as appropriate control valves 40. The plug 32 has a discharge conduit 46 which communicates the area between the two plugs and a properly installed valve 48.

The newly installed folded pipe, with the plug inserted at the opposite end, is heated internally by circulating live steam through a small passage provided in the folded portion of the new pipe, which is clearly shown in FIG. The valve 48 at the downstream end is opened, so that the entire length of the new pipe is heated. The valve 48 is then closed and pressurized steam continues to flow through the plug 30, pressurizing the folded pipe, reshaping it and expanding it in a round shape. If the new pipe is made in a folded form, it must be cooled after obtaining a round shape and maintained at an internal pressure such as cold air pressure, so that the leaves are fixed in a round shape. This last step is not necessary if the pipe is manufactured in a round shape, except for the process of expanding or straightening the original diameter beyond the original diameter.

If the new pipe is not provided with an internal passage as in the case where the new pipe is folded completely flat as shown in FIG. 3, before the new pipe is inserted into both ends of the plug 30, 32, Just as the live steam is circulated through the existing pipe, it must be heated outside the new pipe. Then, for a new pipe heated over its entire length, the plugs 30, 32 are easily inserted into the opposite ends, the valve 48 is closed and the live steam and hot water are plug 30. It is introduced through to expand the folded pipe and reshape it into a round shape.

6 shows another form of a device for expanding a collapsed pipe. This device consists of a mandrel 50 with heating means 52 capable of heating the new pipe in a flexible state. The mandrel 50 is connected to a traction cable 54 or other means for drawing a new pipe through the original pipe. Upon heating the mandrel and tensioning the traction cable, the mandrel is drawn through the original pipe, expanding the new pipe to the desired diameter. As can be seen from this method, the traction cable 54 is inserted into the new pipe before folding to insert the new pipe into the existing pipeline.

A third method of heating, rounding and expanding a new pipe is hot water or steam down the existing pipe to be repaired alongside the new pipe until the desired temperature is obtained at the downstream end of the new pipe which is installed but still folded. It includes the process of supplying. The new pipe is then pressurized with hot water or steam and expands under pressure into a round shape to the desired diameter.

[Yes]

In a specific pipe reforming process, conventional PVC pipes have an outer diameter that is smaller by about 3.8 cm than the inner diameter of the pipe to be repaired. PVC pipes, as mentioned above, have a wall thickness of a standard size ratio to the outside diameter. The PVC pipe is heated to at least 93.3 to 98.9 ° C. (200-210 ° F.), shrinking to the form shown in FIGS. 3, 8 or 38e. The folded pipe can be transported to the job site while stored in a large spool. During installation in underground conduits and the like, it is desirable to be reheated in the hot box 18 so that it can be draped down vertically through the deep manhole and bent and easily drawn horizontally through the conduit. When the folded pipe is installed in a predetermined section of the existing conduit, it is plugged, heated and rounded. If necessary, it can be inflated beyond the original or designed round diameter and can be inserted snugly against existing pipeline sections.

[How to find the location of the connection of the building sewer pipe]

The advantage of expanding the newly installed thermoplastic pipe beyond its original design diameter has been illustrated in connection with FIG. 36, where the existing pipeline section to be repaired intersects with at least one building sewer pipe or other incoming side pipe. In FIG. 36, the main pipeline 70 intersects at the inlet 72 with an incoming side pipe 74, such as a building sewer pipe. When a new thermoplastic pipe is installed in the main main pipeline 70 and rounded and expanded or straightened beyond the original rounded diameter to fit tightly to the inner wall of the main pipeline 70, the expansion or dimple ( 76 is formed in the opening or the connecting portion 72 of the main pipeline and the inlet side pipe. In effect this expansion 76 is an indicator of the exact location of the opening of the inlet side tube leading to the main pipeline. Passing the television camera through the main pipeline determines the exact location of the inflation or dimple and the exact location of the opening in the inlet side tube. Thereafter, a remote controlled cutting mechanism 78 can be introduced through the main pipeline into the correct position of the inflation portion and used to cut the inflation portion 76 from the new pipe 80, leading to the main pipeline. The entrance and exit of the bystand 74 is resumed.

The process of rounding, expanding or unfolding the newly installed thermoplastic pipe is evident by the following description of the method or further embodiments already described.

[Preferable Shape of Folded Pipe]

Although the flat folded thermoplastic pipes of FIGS. 3 and 38e are suitable for use in the installation process described above, the preferred form of such folded pipe 10 is shown in FIG. The thermoplastic pipe 10 of FIG. 8 is manufactured in the folded form shown. The pipe is folded along a convex longitudinal fold 82, into a pair of top and bottom legs that include a long leg 83 and a short leg 84. The long leg 83 forms a small longitudinal passage 86 through the folded pipe ending at the curved or convex free end 85. Short leg 84 also ends at the curved or convex free end 87 that penetrates the pipe to form longitudinal passageway 88. Moreover, the flexible folded portion 82 defines a passage 89 from one end to the other end of the pipe along its interior.

The ends of the convex folds and legs as described above are important in preventing the folds from breaking if the pipes are folded flat in the manner shown in FIG. 3, especially if the walls of the pipes are thick. Passages 86, 88, and 89 are also important for passing steam or other hot fluids over the entire length through the folded pipe for reheating and reworking after the folded pipe is installed in the underground conduit. Without this passage inside the fold, reheating would be a long slow process and difficult to achieve.

In the repair of a building sewer pipe, such as the building sewer line 90 shown in FIG. 7, the pipe of the folded form as shown in FIG. 8 is introduced into the building 96 from the intersection 92 with the main pipeline 94. It is particularly suitable for use as a replacement pipe. The installation of replacement pipes in such building sewers creates special problems due to the nature of such sewers. First, entry and exit problems, because these side tubes often pass under grass, trees, and shrubs and cannot be accessed by manholes. Excavation to repair existing side tubes is very expensive. In the case of inserting a new sidewall into an existing sidewall in the basement, its entry and exit is normally only done in a single small vertical excavation 98 adjacent to the building, as shown in FIG. These excavations have little room for moving large scale equipment.

Secondly, building sewer pipes usually have a much smaller diameter than the main building and sometimes have sharp bends or bands, unlike the main building which typically extends straight from the manhole to the other manholes. For example, building sewer 90 has a bend at point 100, making it impossible to insert a straight rigid pipe into an existing side pipe. In FIG. 7, the building sewer 90 entering and exiting the vertical excavation 98 adjacent to the building 96 extends down the grass 102 to the main building 94 at a significant depth below the road 104. The method and apparatus to be described are particularly suitable for solving the unique problem associated with installing replacement side pipes from a single, generally vertical, single entry and exit opening into an existing side pipe underground. This method and apparatus utilizes the form of manufacture of the folded thermoplastic pipe shown in FIG.

[Method and apparatus for manufacturing thermoplastic pipe in folded form]

9-11, the thermoplastic pipe folded as in FIG. 8 is produced using a conventional plastic pipe extruder 106 that extrudes into a vacuum box 108. Traction means 110, consisting of a series of opposed pinch rolls 111 and 112 downstream of the vacuum box, draw the steam tube 114 to pull the extruded material under tension from the vacuum box and reheat it to a deflectable state. The folded pipe obtained is immersed in a folded form on the author spool 116 located in the hot box 18 of FIG.

Die 118 and pin 120 are located at the outlet of the extruder. Between the downstream end of die 118 and the inlet to vacuum box 108 there is a gap 121 of about 30.48 to 60.96 cm (12 to 24 inches).

The vacuum box is divided into three sections internally by the partition plates 122 and 123. All three sections are filled with water up to level 124 in the box. The upstream or first section of the box is connected to a vacuum source 125. Although the entire vacuum box is under negative pressure because of this connection, the maximum negative pressure is in the upstream section of the box. Correction means 126 is provided in the first section of the vacuum box. The correction means, when the extruded plastic material is cooled and solidified, mold and hold the material to a desired folded shape. The water in the vacuum box functions to cool and the vacuum applied to the box cooperates with the correction means to keep the plastic material in the desired folded shape until it can maintain such shape without restraint through cooling.

10 and 11, the correction means comprise a series of correction plates 128, which are arranged in a spaced state, assembled together by an assembling rod 130, and the spacers between the plates ( spacer 132). Assembly rods 130 are screwed at both ends and fastened by nuts 134. The compensator plate 128, which is closer to the inlet end of the compensator, is more tightly spaced apart from each other than downstream compensators because of the superior plasticity and flowability of the compensator at the inlet end, thereby increasing the need to maintain the extrusion shape in the compensator of that portion. The compensator also has a central tube 136 with an orifice 137 that delivers cooling water between the plates for more rapid cooling of the plastic material.

In FIG. 11, each compensating plate 128 has an opening 138 formed and retained in the compensating plate and precisely cut to fit the shape and external size of the folded pipe. Comparing FIGS. 8 and 11, the opening 138 of the compensating plate has a short leg 138a corresponding to the short leg 84 of the folded pipe, and a fold 82 rounded along the length of the pipe. In addition to the round fold portion 138c corresponding to the long leg portion 138b corresponding to the long leg portion 83 of the pipe.

In making the pipe of FIG. 8, the raw plastic mixture, such as polyvinyl chloride, is extruder 106 through feed funnel 107 where the material is heated to a high temperature of, for example, about 182 ° C. (360 ° F.). The plastic (flexible) material, which is fed to the die, and is extruded through the die 118 where it is very hot, encounters the fin 120. Dies and pins are standardized to mold the plastic material into the shape and final size of the desired tube. This plastic material is fed along the gap 121 to the first section of the vacuum box 118 and passes through the calibration plate. The compensating plate molds and holds the plastic material (material) in the shape and size determined by the opening 138.

Since this plastic material first enters the compensator, it can be very hot and rather fluid, so that the compensator plate 128 keeps the desired shape very close to each other at this point. The vacuum in the box supports the plastic material about the outer periphery of the opening 138 when the coolant cools the plastic material. If desired, the internal passages 86, 88 of folded plastic material in order to ensure that the compressed air injected from the vacuum source 140 to the fin 120 maintains the tubular shape of the pipe without the plastic material being fully folded. ), 89 can be passed downstream. The plastic material may be shaped at itself under the tension caused by the traction roll 110 at a time point reaching the downstream end of the compensator 126. This roll pulls the folded plastic material out of the vacuum box into a continuous strip shape. From the compensating plate, the strip moves gradually through the second and third chambers of the vacuum box installed. The strip is cooled at the time it leaves the vacuum box and is in the form of rigid (i.e. hard) shown in FIG. Traction roll 110 adjusts the thickness and other numerical factors of the wall of the folded pipe by pulling the strip or flow of plastic material from the extruder under tension.

The folded strip is fed from the traction roll 110 to pass through the steam tube 114, which is connected to a steam source 115 through an inlet opening 117 to supply steam to bend the strip. Reheating allows the strip to be wound onto storage spool 116.

The number and spacing of compensating plates used in the compensator are a function of the extrusion rate as determined by the roll and the desired wall thickness of the finished pipe.

As described above, the spool 116 in which the folded pipe 10 is stored is preferably installed in the hot box 18 shown in FIG. 4 for movement in the field.

Method, apparatus and apparatus for installing thermoplastic pipes in side tubes

7 not only illustrates the sewer side pipe as described above, but also illustrates a method, apparatus and mechanism for inserting the folded thermoplastic pipe of FIG. 8 into the side pipe. Firstly, the vertical excavation 98 is preferably dug as close as possible to the building 96 introduced by the side tube 90 to provide an entrance through the existing side tube 90.

The length of the lateral sewer pipe to be repaired or replaced is determined by inserting the flexible fiberglass rod into the lateral sewer pipe at the excavation and feeding the rod through the lateral sewer pipe until it intersects the main pipe 94. In this way, the length of the rod in the side tube can be indicated on the entrance and exit, and then the rod is taken out to measure the length to determine the length of the plastic pipe 10 required for the operation. Knowing the length of a series of lateral sewer pipes to be repaired, the folded pipe 10 can be cut in advance to correspond to the measured length in a manufacturing plant or other location away from the work site. It is then transported to the work site to install a pipe of precut length.

Alternatively, the required length can be cut at the work site from the spool 116 or 12 (FIG. 4) in the hot box 18 taken to the work site. If the truck 20 equipped with the hot box 18 is not accessible as an excavation for the lateral sewer pipe to be repaired, the plastic pipe 10 of the required length is a small wheeled hot box that can be moved to each excavation. Stored in a small spool). A small mini hot box 140 with a spool 142 of folded pipe 10 is shown in FIG.

Alternatively, instead of measuring and cutting the plastic pipe 10 folded to a length corresponding to the length of the lateral sewer pipe to be repaired, a new folded pipe is heated in the hot box 140 to intersect with the main pipe 94. After supplying to the side sewer pipe to the part, you may cut in a spool.

In addition, if the folded plastic pipe 10 is cut in advance in the factory by length, it is moved to various work sites according to the precut length, and heated by the steam tube 114 shown in FIG. 9 to be inserted into the side sewer pipe. It may be. The steam tube can be made of canvas or metal or equivalent and has a flexible fabric or equivalent end that can be wrapped around a folded plastic pipe to retain steam on its inner surface. These tubes are light and can be easily carried to the field and can be more than 20 feet (6.1 m). Canvas vapor tubes are preferred over metal tubes because of the weight considerations required in the field of use.

If the lateral sewer pipe is straight and the entry and exit opening of the lateral hot pipe at the rig is sufficiently close to the surface or the rig is wide enough, simply insert the new pipe into the existing lateral sewer pipe until the leading end of the new pipe reaches the main building. By pushing in, it is possible to insert the required length of the folded plastic pipe 10 into the lateral sewer pipe. However, this method is sometimes impossible because of the need to pass a new pipe along the bends of the excavation, side drains, or both. In this case it is usually necessary to heat the rigid folded plastic pipe to bend in the longitudinal direction to pass the bend, and it is better to tow the lateral sewer pipe than to push the new folded pipe. With no access opening at the main end side of the lateral sewer pipe, towing the flexible folded plastic pipe to the lateral sewer pipe presents a special problem mentioned in the present invention.

How to pull a new side tube from an entry opening into an existing side tube

One method of inserting a new lateral sewer into an existing lateral sewer by traction involves using a traction cable attached to the leading end (tip) of the new lateral sewer. The cable passes around the pulley at the connection of the main and side sewers and is led back to the inlet of the side sewers. By applying traction to the traction cable from the entry and exit opening in the excavation 98, the new pipe can be towed over the entire length of the existing lateral sewer pipe. This method uses special tools.

First, the inlet end of the new lateral sewer pipe should be clamped to limit the size of the through-holes 86, 88, and 89 shown in the eighth, so that after the pipe is inserted into the existing lateral sewer pipe, While pressurized, the hot fluid can be passed through the folded pipe and heated over its entire length, thus allowing it to deflect for expansion and rounding. To achieve this limitation and end clamping, an end clamping device as shown in FIGS. 12 and 13 is used. A side view of the end clamping device is also shown in FIG. 22. Referring to the above three figures, the end clamping device 144 has a pair of rigid metal plates. The plate consists of a top plate 145 and a bottom plate 146 opposite it. Both plates have nose portions 147 through which the centered traction cable connecting holes 148 penetrate in a row and protrude forward. The pair of centered holes 149 extend through the bottom plate and the top plate toward the rear of the cable connecting hole 148 to accommodate the clamping bolt 150. The bolt 150 also extends through the perforated hole 151 to be centered through the folded plastic pipe 10.

In order to install the end clamping device 144 at the leading end of the folded plastic pipe 10, the leading end of the pipe is heated to be able to be bent, for example by the end heater 152 shown in FIG. 24. The end heater 152 includes a thin rigid pipe 154, one end of which is closed by an end plate 156 having a central inlet 157 with a steam hose connection 158. The opposite end of the heater includes a flexible canvas or other suitable fabric wrap 160 that is bound to the pipe 154 at the connection band 162. The free end of the wrap 160 is bound to the pipe 10 so that steam can escape from the folded plastic pipe 10 and the wrap's connection 164 so that the entire end of the pipe is connected to the steam through the connection 158. When sprayed into a pipe, it is heated to a desired temperature. The length of the pipe 154 can be long or short, depending on the conditions of use, but is preferably approximately 0.61 m (2 feet).

After allowing the leading end of the pipe 10 to bend, the plates of the end clamping device 144 are fastened to the ends of the pipe, and the bolt 150 penetrates and tightens the bolt holes 151 to face the opposite plate 145. ), 146 tightens the middle portion of the folded pipe in a more flat state, so that the folded pipe reduces the size of passages 86, 88, 89 at the ends. The width of the clamping plates 145, 146 is narrower than the overall width of the folded pipe 10 so that the passage 89 at the fold and the passage 86 at the end of the long leg restrain the folded pipe. It should be noted that when applied, it is not completely closed. When such a restraining force is applied, the fluid can pass completely through the clamped end of the pipe, and the size of the passageways is small enough to create a pressure such that the internal pressure of the folded pipe can expand and round the pipe.

It will be apparent from the following description that the above end heaters are useful for other purposes.

[Releasable End Clamp]

Another form of end clamp device that can be used in place of the end clamping device 144 is the releasable end clamp device 250 shown in FIGS. 39-41. The clamping device 144 introduces a pipe 10 when inserted into a conduit that is difficult to see without cutting the clamped end of the conduit using a special remote automatic cutting mechanism, as shown in FIG. 22 to be described later. The drawback is that it cannot be removed from the end. However, the releasable end clamp device 250 can be remotely released from the clamped end of the new pipe, if desired, and towed by a cable in an existing conduit.

The releasable clamp device 250 includes an upper jaw 252 pivoted at point 254 relative to the lower jaw 256. The lower jaw 256 includes a tip protrusion 258 that extends to attach the traction cable 262 and has a traction cable hole 260. Jaws 252, 256 have forceps ends 263, 264 that compress and grip the leading end 266 of folded plastic pipe 10 that is heated to bend.

The bolt 268 passes through an opening 270 in which the bolt is larger than the head 269 and extends through a small bolt hole 272 that is centered in the lower jaw 256. Bolt hole 272 is smaller than nut 273 and head 269 of bolt 268. The bifurcated release wedge member 276 forms a slot 280 and has parallel arms 277, 278 that are coupled to a vertically formed wedge body 282. The flexible release cable or cord 284 is attached to the body 282 through the body hole 286. The wedge member 276 is designed to be wedge fixed between the head 269 of the bolt 268 and the upper surface of the upper jaw 252, and the arms 277, 278 extend below the head and have a slot ( 280 receives a bag of bolts. The bolt head 269 is thus arm 277, 278 without passing through the upper jaw opening 270 when the bolt is tightened to clamp the jaw ends 263, 264 to the pipe 10. ).

After the new pipe is towed to the existing lateral sewer using the traction cable 262, and after the new pipe is rounded except the clamp end, the release cable 284 is towed to release the clamp device from the new pipe. do. Thus the wedge member 276 is pulled under the nut 273 if the bolt head 269 (or the nut end of the bolt is above the upper jaw), causing the bolt head to fall through the large opening 270 in the upper jaw 252. The jaws release the pipe ends so that the pipe ends are open The wedge member and the clamp device are pulled from the side sewer or main pipe using their respective traction cables.

[Poly and Cable Frog]

Other mechanisms used to pull the new folded lateral sewer pipe from the entry opening 98 into the existing lateral sewer pipe are pulleys and cable means called frogs shown in FIGS. 14 to 16. The frog 152 includes a cable pulley wheel 154 rotatably mounted in the pulley housing 156 on the shaft 157. A pair of angled legs 158 is attached to opposite sides of the open trailing end of the pulley housing. Each leg includes a front leg 158a and an integral rear leg 158b. Hanging backward from the rear leg 158b is a pair of leg guide bands 160 made of flexible steel twisted inwardly at the rear end 161. The pivot connection 162 of the leg 158 to the housing 156 is spring-loaded to push the leg outward as shown in FIG. However, the legs can be pivoted inwards towards the position shown in FIG. 15 so that the legs and the entire assembly can move through the lateral sewage.

A pair of generally triangular arms 164 are pivoted at the joints of the front and rear legs 158a, 158b at the biased (spring-forced) pivot connection 166. The biased pivot connection 166 causes the arm 164 to be in the extended position at right angles to the rear leg 158b when in the extended position as shown in FIG. However, arm 164 can be folded in response to spring pressure, such as the folding value shown in FIG. 15, in which case the frog is moved to its destination through the lateral sewer pipe. Traction cable 168 with both ends returning to the entrance opening 98 travels around pulley wheel 154.

With the traction cable 168 installed and both ends of the cable returning to the entry and exit 98, the frog is inserted into the existing axial sewer pipe using a flexible fiberglass push rod (not shown). . When the frog reaches the intersection of the lateral sewer pipe and the main building, the housing 156 and the pulley connected thereto are pushed into the main building and the front leg 158a enters the main building, the arm 164 is moved by elasticity. It is pivoted outward from the position shown in FIG. 15 to the open position shown in FIG. In the open position of the leg, the rear leg 158b and the guide band 160 connected thereto are pressed against the inner wall of the existing side sewer pipe. At this point, both ends of the traction cable 168 are towed to securely mount the frog at the junction of the side sewer pipe and the main pipe.

While continuing to apply tension to the traction cable so that the anchored frog is held in place, one end of the traction cable is either end clamping device 144 (FIGS. 12-13) or releasable end clamp device 250 (first 39-41). The other end of the cable, which is still in the entrance opening 98, is towed to the leading end of the folded pipe 10, which is heated and deflectable, until the lateral sewer pipe where the prog 152 is located and the main building reach the intersection. Pull the plastic pipe 10 folded to pass around the side sewer pipe and the bend 100. Traction force can be applied to cable 168 using manual or power winch 170 (FIG. 7) at entrance opening 98. FIG. Since it is a triangular arm 164, the vertical movement of the frog due to the tensile force applied to the cable 168 is prevented.

After the new folded plastic pipe has reached the prog in the main building, the cable connection to the pipe end clamp device is released and the end of the cable is towed through the pulley to drop the prog into the main building. The cable is then drawn out of the inlet line at the inlet opening and the frog is recovered from the main building after a short time using conventional drawing methods. At this time, the folded plastic pipe 10 is completely inserted into the side sewer pipe to be repaired, together with the introduction end clamped in the main pipe. The folded plastic pipe is ready to be reheated and expanded in a round shape in an existing incoming lateral sewer.

Before discussing the expansion and rounding process applied to the incoming lateral sewer, the means and methods of releasing the traction cable 168 from the end clamping device 144 will be described so that the traction cable 168 can be towed through the frog. . This is accomplished in several ways, for example as shown in FIGS. 34 and 35.

34 illustrates a cable release scheme called a break scheme. In this method, the slack end 168a of the traction cable 168 is attached to a breakable string or cable 172 of relatively low strength, the cable 172 being folded into a lateral sewer pipe 10. ), Followed by tape or the like at 173. At the slack end 168a, the traction cable 168 is loosely wound through the cable hole 148 in the end clamp into the loose loops 168b, 168c, as shown, and pulled through the pulley of the frog. The towing end of the cable is held from the entry opening to the lateral sewer pipe. If no end clamp is used, the cable hole 148 may be drilled directly through the folded leading end of the plastic pipe. The string 172 receives the appropriate tension on the slack end 168a of the cable as it pulls the cable through the frog to position the new pipe with the winch folded in the entry and exit into the existing lateral sewer. When the leading end of the folded new pipe reaches the frog, the tensioned end of the cable suddenly acts to break the string 172 and release the slack end 168a of the cable through the cable hole 148 to release the cable. Can be withdrawn.

35 illustrates a cable release method similar to the manual cable release method. This method is loosely wound twice through the cable hole 148 at the leading end of the new folded pipe 10 so that the slack end 168a of the cable 168 forms a double loop 168b, 168c. . The traction cable 168 is then introduced into the program through the existing lateral sewer pipe 90 and back to the inlet opening. The slack end 168a of the cable should be longer than the length of the new pipe 10 to be inserted. When the winch seals the new pipe into the existing side sewer, the appropriate tension is maintained at the slack end 168a of the cable, pushing the new folded pipe into the side sewer. When the new pipe is properly inserted into the lateral sewer pipe, the slack end 168a of the cable is released at the inlet opening and is towed freely at the leading end of the newly inserted pipe through the cable opening 148.

Method and apparatus for expanding and rounding folded pipes in side tubes

With the folded new pipe located in the existing side pipe, the pipe is ready to be expanded and rounded to replace the side pipe with a new incoming side pipe. At this time, since the introduction end of the folded new pipe 10 is already restrained (suppressed) by the end clamp devices 144 and 250, the folded pipe can be pressed internally by the fluid, and also hot steam or Other fluids can pass through it. This allows the folded pipe to be heated to a state in which the entire inner length can be bent for expansion. Of course, at this time, the trailing end of the newly inserted folded pipe is covered to introduce hot steam or other fluid for heating and expansion. This capping means or plug is shown in FIGS. 17-21.

A so-called topedo plug 176, conical plug, has a conical portion 178 having an orifice 180 at its inlet end. Cone 178 extends rearward to a short cylindrical portion 182 covered by trailing end plate 184. End plate 184 has an inlet 186 and a hose connection 188 that couples a steam or hot water supply hose so that hot pressurized fluid enters the interior of the folded pipe. A hose connection, such as an air hose connection, may be provided through the end plate 184 to maintain the air pressure in the expanded pipe when using the air pressure to expand the pipe or to restore the pipe to its expanded state. Can be.

By allowing the tail end of the folded pipe 10 heated using the end heater 152 described above to bendable, the cone of the topedo plug 176, as shown in FIG. Until the new pipe is in contact with the end edge, it is pushed into the trailing end of the pipe 10 to inflate the end of the new pipe in a round shape that matches the outer diameter of the cylinder 182. The adjustable chain clamp 190 is used to clamp the expanded end of the new pipe against the cylindrical portion 182 of the torpedo plug to seal the pipe against the plug.

The chain clamp 190 is shown in detail in FIGS. 20 and 221. The chain clamp includes a clamping plate 192 having a curved pipe engagement surface 193. On the convexly curved outer surface of the plate is mounted a U-link (clevis) 194 in which the nut member 195 pivots between. The nut member 195 houses a threaded rod 196 having a wrenching end 197. Clamping chain 198 is connected to the opposite end of the rod. The chain is preferably a transmission chain or a bicycle chain. The chain is adjustablely connected to the anchor post 199 on the outer surface of the clamping plate 192.

With the end of the pipe 10 heated and bendable, with the torpedo plug 176 inserted at that end, the clamping plate 192 is located on the round pipe end and the chain 198 is a cylindrical pipe end. It is wound around and secured to anchor post 199 by hand as tight as possible. Clamping pressure is applied by rotating the screw rod 196 in a direction to shorten the effective length of the clamping chain 198 using a wrench mechanism (tool) applied to the wrenching end 197 of the rod. Since plastic pipes tend to deform when heated, it is important to clamp the clamps easily, and the clamps must be tight enough to be in place during the heating and rounding process of the new pipe.

With the topedo plug clamped in place at the trailing end of the newly inserted pipe, the steam hose is connected to the plug connection 188. The hot steam is forced through the length of the folded pipe, in particular through small passages through it, causing the entire length of the pipe to heat up. At the same time, the constraint that the folded pipe is exerted by the end clamp at the inlet end causes the pipe to be pressurized internally to about 24 PSI (1.68 kg / cm 2). As the pipe is heated and pressurized, it expands and rounds in a cylindrical shape over its entire length except for the clamped end.

When the new pipe is rounded to the desired dimensions and rounded against the inner wall of the existing side sewer pipe, the plastic pipe is newly rounded, for example by cooling while maintaining the internal pressure through the inflow of air under constant pressure. Is stabilized. When the new pipe is stabilized, the chain clamp is released at the trailing end of the pipe and the toppedo plug is also removed.

How to remove the clamped end of a new pipe

The next process is to remove the folded and clamped inlet end and the end clamp of the new pipe from the remaining rounded parts of that pipe. This is accomplished by cutting the introduction end folded and clamped from the new pipe which has been expanded and rounded as shown in FIGS. 22 and 23.

22 and 23 show cutting means for cutting the folded and clamped inlet end of the pipe 10 which has been expanded and rounded in the existing pipe. The cutting means consists of a cutting mechanism 200 which is powered. The cutting mechanism includes a small high speed motor or air motor 202 embedded in a cylindrical motor housing 204 that is smaller than the inner diameter of the rounded plastic pipe 10. The flexible air hose or power cord 206 powers the motor 202 from the power source floating at the inlet opening to the existing incoming lateral sewer. The rotor 210 is mounted on the motor drive shaft 208, and a pair of cutting or flailing braids 212, 213 is pivotally mounted on the pivot connecting portion 214 adjacent to the outer end of the rotor. .

The motor housing 204 is housed in an inflatable rubber sleeve 216 that, when inflated, secures the cutting device in place in a round plastic pipe. The flexible air supply hose 218 supplies compressed air to inflate the sleeve 216.

Although the illustrated braids 212 and 213 are made of steel, they may be made of chains or cables. In addition, as the rotor 210 rotates, the braid is designed to extend outward under centrifugal force, thereby cutting the plastic pipe 10.

In use, the cutting device 200 is pushed downstream through the pipe 10 after the new plastic pipe 10 is installed and rounded. Pushing is accomplished by the flexible fiberglass rod and the retracted rubber sleeve 216. The cutter is pushed into the existing side sewer until it reaches the folded and clamped inlet end. At this point, the sleeve 216 is inflated to allow the cutting device to be centered and mounted in the round plastic pipe. With the sleeve inflated, power is supplied through the air hose or power cord 206 to drive the motor 202. The motor rotates the rotor 210 to drive the foil braids 212, 213 until the braid cuts the ends of the clamped and folded plastic pipe. The cut end is dropped into the main tube and then can be drawn out by conventional methods.

After cutting the leading end of the pipe, the sleeve 216 is retracted and the cutting device is simply pulled out of the rounded plastic pipe by pulling the power cord 206 and air hose 218 from the inlet end of the new pipe. It is sunrise. The new lateral sewer pipe is installed in the existing lateral sewer pipe, connected to the side sewer pipe introduced into the building 96 (FIG. 7), and then is ready for use.

Other methods and apparatus for installing and expanding new pipes in existing side tubes.

FIG. 33 illustrates another method of pulling the folded plastic pipe 10 through the entrance opening 98a and into the existing side sewer 90a that intersects the main pipe 94a at the intersection 92a. At a point spaced apart from the intersection portion 92a by a predetermined distance, the main building 94a is provided with a manhole 216 for entering and exiting the main building 94a. Cable location 218 is fixed to manhole 216. The introduction end of the traction cable 220 is guided from the entry opening 98a to the existing side sewer 90a by a flexible fiberglass rod having an introduction end equipped with a gripper for gripping the introduction end of the traction cable. , It is pushed to the intersection portion 92a downstream of the side tube.

When the leading end of the push rod has reached the intersection, it can be bent by turning the corner to the main building. At this time, the push rod continues to push the traction cable 220a through the main pipe until the introduction end of the traction cable reaches the manhole 216 as shown by reference numeral 220a. The leading end of the towing cable is attached to the cable winch at position 219. The trailing end of the traction cable 220 still in the entry opening 98a is connected to the leading end of the folded new pipe 10 using one of the cable release methods described above. The new pipe is heated to bend, for example in hot box 18, and then pulled into existing side tube 90a by cable 220 using winch 218 in manhole 216. This towing continues until the leading end of the new pipe 10 reaches the intersection 92a. The traction cable 220 is then released at the leading end of the new pipe using one of the methods described above. The new pipe is ready to be expanded and rounded in the existing side tube 90a using the rounding method or other method described above.

[How to round pipes using inflatable plugs]

Another method and apparatus for inflating a newly installed plastic pipe in an existing incoming side canal is shown in FIGS. 25-29. This method is known as using an inflatable (expandable) plug. The inflatable plug 222 used in this method is shown in FIGS. 25 and 26. In this method, instead of the end clamp device 144 (FIGS. 12-13) or the end clamp device 250 (FIGS. 29-41), which limits or seals the leading end of a new plastic pipe that is difficult to enter or exit. By using plugs, these pipes can be pressurized, rounded and expanded. The plug is designed to accommodate air pressure of at least 25 PSI (1.75 kg / cm 2) to expand the outer diameter of the plug to the size of the inner diameter of the new rounded pipe, but does not rupture if not constrained by the new pipe. The plug must also be designed to withstand temperatures in excess of about 93.3 ° C. (200 ° F.).

The inflatable (inflatable) plug can be composed of a single layer of flexible material, as long as it meets the above specifications. However, no suitable material has yet been found. Therefore, two-layer plugs are currently used. The plug is folded, blocked and sewn at the front end 225 to consist of a closed outer canvas tube or other fabric tube 224. The flexible outer canvas tube 224 has an expanded diameter where the new pipe, when rounded, corresponds to the desired inner diameter. The trailing end 226 of the canvas tube remains open. An inner brader or inner tube 228 of inflatable rubber is located on the inner surface of the outer canvas tube 224. The total length of the plug may vary from about 0.305 m (1 ft) to 6.1 m (20 ft) depending on the application. The trailing ends of the outer canvas tube and the inner rubber tube are gathered around a pipe stem 230 that provides an air hose connection 232 for the air or vapor supply hose 234 that supplies the fluid under pressure into the inner tube. . The trailing end of the inner and outer tubes are gathered around the pipe stem 230 and tightly coupled by the band clamp 236 to prevent leakage of pressurized fluid from the inner tube.

An inflatable plug as described above is typically used when installing and routing (rounding) a new incoming side tube, thus eliminating the need for the end clamps and end cutters described above. A typical method of using an inflatable, ie, inflatable plug is as follows.

The desired length of the folded plastic pipe required for the retraction side tube to be repaired is, for example, heated and rounded in the workplace using the steam tube described above. A hose 234 for pressurizing the plug is inserted through the length of the round plastic pipe connected to the plug until the inflatable plug is positioned at the leading end of the round plastic pipe.

At this time, the round plastic pipe of the predetermined length is reheated and folded again with the contracted plug and hose inserted inside. FIG. 27 shows a state where the air hose and the plug 222 contracted and connected thereto are inserted into the round plastic pipe 10. FIG. 28 illustrates folding the pipe 10 again with the contracted plug 222 and the hose 234 inserted into the folded pipe inner surface.

At the site, the plastic pipe is heated, folded into the side tubes to be repaired and inserted with flexibility. Once fully inserted, the folded plastic pipe is heated like a plug that shrinks as steam passes through it. When the entire length of the installed plastic pipe is heated, the plug 222 is inflated and expanded through the air hose 234, and the inlet end of the plastic pipe 10, which is still hot and deflectable, surrounding the plug, can be completely blocked. Will be. After the plug is inflated, the plastic pipe on the top of the plug is compressed by heated compressed air, ie along the hose 236 which is introduced into the topedo plug 176 at the trailing end of the new pipe in the entry opening 98. Pressurized, rounded and expanded by air.

The new plastic pipe is completely rounded to the desired diameter in the existing side tube 90, inflated and then cooled, so that the plug 222 is retracted and drawn out of the newly rounded pipe 10 by the air hose 234. . The newly installed plastic side tubes are ready for use.

[Other ways to use inflatable plugs]

30-32 illustrate another method of using the inflatable plug just described above.

A slight variation in the method illustrated in FIGS. 27 to 29 is the use of inflatable plugs as sliding plugs in the process of rounding pipes. According to this variant, the inflatable plug 222 and its air hose in FIG. 30 are installed in a pre-rounded plastic pipe 10 as described and folded with the pipe, but the plug is at the leading end of the pipe. It is located about 15.24 cm (6 inches) from 238 and allows such an introduction end to be folded as compactly as possible for easy insertion into existing side tubes. The folded pipe 10 with the contracted plug 222 on the inner surface is folded and installed before being inserted into the existing side pipe. The trailing end of the new pipe is covered by a toppedo plug 176 with an air hose 234 extending through the seal in the topedo plug.

With the inflatable plug 222 retracted, the folded pipe is heated by steam passing through it to bend over its entire length. The air hose 234 extending from the topedo plug 176 is pulled tight, and the clamp 240 is positioned in the hose about 30.48 cm (12 inches) past the trailing end of the topedo plug.

If the folded new pipe becomes hot, the inflatable plug is inflated. The new, folded pipe between the inflated plug 222 and the topedo plug 176 is also pressurized with compressed air blown through the air line 236 and through the topedo plug. Pressurization of the new pipe causes the inflated plug 222 to slide toward the inlet end 238 of the new pipe until the clamp 240 abuts on the rear end of the topedo plug and stops. At this time, the introduction end is completely rounded like the rest of the newly installed pipe. The inflated plug 222 is retracted and drawn from the newly installed pipe.

FIG. 32 illustrates another method of blocking, rounding and inflating a new pipe using an inflatable plug 222 in an existing sidewall or other conduit having an entrance only at one end.

According to this method, the new pipe is inserted into the lateral tube using one of the aforementioned insertion methods and folded without the inlet end clamp or inflatable plug for constraining or sealing the inlet or downstream end of the pipe. However, the remaining length of at least about 3.05 m (10 feet) of the folded plastic pipe is left to be exposed at the entry end to the existing side tubes. The folded pipe is internally steam heated to allow it to bend over its entire length. When hot, the outer clamp 242 is applied to the folded pipe about 3.05 m downstream of the topedo plug 176. The top 3.05 m of the plastic pipe between the clamp and the toppedo plug is then rounded by injecting steam from line 236 into the top 3.05 m of the folded pipe through the topedo plug. The rounded 3.05m pipe is cooled in a rounded state.

The topedo plug 176 is removed and the inflatable plug 222 is inserted with at least some bulge to facilitate insertion of the new pipe into the rounded portion. Toppedo plug 176 is inserted back into the end of the rounded portion of the new pipe with an air hose 234 extending from the inflatable plug through the toppedo plug. The clamp 242 is removed from the new pipe and the inflatable plug 222 is retracted. The new pipe can be steam heated internally over its entire length and bend again. When the new pipe is heated, the inflatable plug 222 is partially inflated. The internal pressure in the new pipe, which may be steam or air pressure, is increased, and the partially inflated plug 222 is pushed through the new pipe, where the new pipe is partially unfolded and partially rounded. When the inflatable plug 222 reaches the downstream or inlet end of a new pipe, it is fully inflated to block the end. The new pipe is pressurized with fluid, completely rounded, cooled and secured round. When a new pipe is installed, the inflated plug 222 is contracted and pulled out of the completely round pipe.

[Remote End Pipe Seal]

There is a method and means provided for sealing the space between a new round pipe and an existing pipe intersecting this opening, whether manhole or other pipe. A typical pipe intersection would be at the downstream end of the building sewers entering the sewer mains.

The seal is a compressible rubber sleeve that surrounds the cross end of the folded new pipe. Its thickness is about 0.635 cm to 0.318 (1/4 to 1/8 inch) but may have a predetermined constant thickness. The length is about 30.48 cm to 60.96 cm (12 to 24 inches) but may have any desired length.

If the leading end of the folded new pipe is installed and accessible from a manhole or the like, the sleeve can slide over the folded end surface before the end is rounded. During the rounding of the pipe end (rounding), the sleeve is also rounded. The new pipe is expanded during the rounding process until the rubber sleeve is extruded tightly to form a fluid sealing seal between the new pipe and the existing pipe. Other methods are used to seal the downstream ends of building sewer pipes that are far away and inaccessible. An adhesive rubber sleeve is used. The leading end of the folded new pipe is heated, straightened and rounded before being inserted into the existing pipe. The sleeve with the adhesive applied is attached to the rounded end, which is folded back with the sleeve attached. The folded new pipe is then inserted into an existing pipe using one of the methods described above.

Using the inflatable plugs described above is a preferred method of rounding and inflating the remote end to be sealed. By such a plug, the expansion and thus the sealing is more reliable and complete than other methods.

How to remove installed thermoplastic replacement pipes from existing underground conduits

As can be seen from the foregoing, the thermoplastic pipe 10 is preferably manufactured in the folded shape shown in FIG. Since it is primarily cooled and set to such a folded shape, the thermoplastic pipe maintains a memory about such a shape that tries to return to the original folded shape whenever it is reheated and not restrained. The memory for this folded shape can be advantageously used to remove the damaged surface of such pipes from existing underground conduits.

To remove the damaged thermoplastic pipe from the existing pipeline inner surface, the damaged pipe is heated by passing live steam and, if possible, by passing live steam around its outer surface. When heated, the damaged pipe section to be removed will retract into its original folded shape. This dent and refolding is accelerated by connecting a vacuum pump inside the pipe to lower its internal pressure. When collapsed and folded, the heated plastic pipe is pulled out of an existing pipeline by a cable winch with a traction cable attached to the accessible end of the collapsed pipe.

[How to Heat and Form Thermoplastic Pipes for Insertion]

It is particularly important to heat the folded thermoplastic pipe to be easily inserted if it must pass through a bend in an existing pipe or conduit or if a new pipe must be fed down through a small deep vertical hole. Several methods for insertion have been described above, including the use of hot boxes or long steam tubes. Another method is to heat the inner surface of the existing pipeline into which the thermoplastic pipe is to be inserted. According to this method, a short section of a pipe having a steam connection is connected to the trailing end of an existing pipe to be repaired. The canvas closure on the trailing end of the steam pipe section is locked around the folded new pipe as it is fed into the existing pipe through the steam pipe connection to heat the new pipe during the insertion process. This method can also be effectively used with the other heating methods described above.

The flat folded form of the rigid (rigid) thermoplastic pipe 10 shown in FIGS. 3 and 8 is also important, because it is intended to reduce the overall cross sectional dimension for insertion into existing pipes. This is because it provides the pipe with properties that could not be achieved with other pipes folded or partially folded. First, the flat folded form shown when heated and bendable is conveniently and compactly stored in a long or short length on the spool. The spool can be used to store, reheat, and feed conduits one after another.

Second, in the case of being heated and able to bend, the shape of the illustrated pipe can be inserted into the pipeline rapidly around the bend from a small vertical entrance opening like a manhole, and can be installed in the pipeline around the sudden bend. have. For example, rigid PVC pipes having a thickness-to-diameter ratio within the ranges described above have a minimum bending radius versus rounding when heated in a flat, folded and bent manner in the unique form shown in FIG. 3 or FIG. The ratio of outer diameters will be between 1 and 2. That is, if a typical 10.16 cm (4 inch) diameter rigid PVC pipe is bendable and folded flat as shown in FIG. 3 or 8, it may be about 10.16 cm without damaging the pipe wall depending on the pipe wall thickness. And a curve having a radius of between about 20.32 cm. This minimum bending radius can never be obtained in other known forms of other known rigid thermoplastic pipes which are in a bendable state.

Third, in the case of being heated and able to bend, the folded pipe form shown in FIGS. 3 and 8 can be easily reshaped in a round form and installed so as to be structurally rigid in spite of the aforementioned advantages. Become strong enough to support surface pressure and fluid pressure. The thermoplastic pipe of the present invention thus installed is not just a liner for a damaged existing pipe but a genuine replacement pipe.

While the subject matter of the present invention has been described in terms of several preferred embodiments and variations thereof, those skilled in the art will recognize that many modifications may be made without departing from the spirit of the invention. Preferred embodiments of the invention and all variations and other equivalents thereof will be protected from the following claims.

Claims (14)

A method of installing a replacement pipe made of a thermoplastic material which is rigid at an ambient temperature in an existing pipeline, wherein the maximum size when it is reduced is smaller than the inner diameter of the existing pipeline 14; 70; 990; 90a. Replacement pipes (10; 10a; 80) manufactured in a collapsed and collapsed form to retain a memory for the expanded form of a tubular form expandable in tubular form with a predetermined outer diameter approximately equal to the inner diameter of the existing pipeline. Providing at the entrance to and exit from the existing pipeline (16; 98); Heating the replacement pipe (10; 10a; 80) of a predetermined length so as to be flexible in a longitudinal direction in a reduced form; Inserting an inlet end of the replacement pipe (10; 10a; 80) into the existing pipeline (14; 70; 90; 90a) in a heated and bendable state; Placing the replacement pipe (10; 10a; 80) in the existing pipeline (14 70; 90; 90a); Applying a heat and an internal pressure to the replacement pipe (10; 10a; 80) to round (round) the replacement pipe in a reduced form into a tubular shape; And cooling the replacement pipe to secure it in the form of a tube. 2. The existing pipeline according to claim 1, wherein the existing pipeline is a lateral pipeline (90) connected to the main pipeline (94), and the replacement pipe (10) removes the main pipeline (94) from an entrance opening (98). Is inserted into the lateral pipeline 90 and is disposed in the existing pipeline using pulleys and cable means, so that the first end of the cable means 168 from the entry opening 98 is connected to the main pipeline ( Traction in a direction away from 94 so that the second end of the cable means (168) pulls the leading end of the replacement pipe towards the main pipeline. The replacement pipe (10; 10a) according to claim 1, so as to increase the fluid pressure in the replacement pipe (10; 10a) and to allow hot fluid to pass therein along the length of the replacement pipe (10; 10a). Limiting the flow capacity of the fluid from the opening of the inlet end of the replacement pipe (10; 10a) before applying an internal pressure for reforming the pipe; Injecting heated fluid into the replacement pipe from the trailing end of the replacement pipe (10; 10a) at a temperature and pressure sufficient to expand to form. 4. The fluid flow of claim 3 wherein the fluid flow from the inlet end of the replacement pipe (10; 10a) is to a collapsible and expandable (expandable) flexible plug (222) carried into the folded replacement pipe. By blocking the inlet end thereby. 2. The replacement pipe (10; 10a) of claim 1 further comprises: extruding a thermoplastic pipe material through a die (118) in a hot plastic state to form a tubular shape of a desired size; The openings 138 of the compensating plate 128 of the series of compensators 126 formed to a size that can be collapsed into a desired, reduced form before the high temperature thermoplastic material extruded in a plastic state is subjected to substantial cooling. Applying a partial vacuum to the thermoplastic material at a temperature above which imparts a memory to the thermoplastic material while feeding through; Cooling the shunt pipe while pulling the folded pipe through the compensator plate 128 of the compensator 126 to maintain (solidify) the folded pipe in a reduced form; Reheating the folded pipe so as to have the flexibility to bend the folded pipe in the longitudinal direction but remain below a temperature that can change the memory properties of the thermoplastic material; Produced in a folded state in which the pipe, which is flexible in the folded form, is stacked. 2. The replacement pipe (80) according to claim 1, wherein the replacement pipe (80) is rounded by applying sufficient heat and internal pressure to form a dimple (expansion portion: 76) in the replacement pipe portion corresponding to the position of the connection portion (72) with the side pipe (74). And remove the dimple of the replacement pipe to locate the dimple (76) and create an entry and exit opening for the connection (72) with the lateral tube (74). The method according to claim 1, wherein the inlet end of the replacement pipe (10; 10a; 80) is rounded, an inflatable sealing sleeve is attached around the rounded inlet end, and the replacement pipe (10; 10a; 80) is attached. Refold the inlet end before inserting into the existing pipeline 14 70; 90; 90a, and after installing the replacement pipe 10; 10a; 80 and the existing pipe 10; 10a; 80 And heating and roundly expanding the replacement pipe (10; 10a; 80) so that the sealing sleeve between the pipelines (14; 70; 90; 90a) is tightly compressed. Way. In the apparatus for installing a replacement pipe inside an existing pipeline, a reduced form in which a fixed length of the rigid thermoplastic replacement pipe 10; Storage means (12; 116; 142), comprising: a housing (18; 140) surrounding the stored replacement pipe (10; 10a); Heating means (24) for heating the interior of the housing (18 140) to change the rigid pipe (10; 10a) to a flexible state; Means for drawing the leading end of the flexible folded pipe (10; 10a) out of the housing (18; 140); Insertion means (22, 23, 26, 28; 144; 250, 262, 276, 284) for inserting the leading end of the replacement pipe (10; 10a) into the existing pipeline (14; 70; 90; 90a) in a heated and flexible state; And pressurizing means for expanding the replacement pipe (10; 10a) inserted into the existing pipeline (14; 70; 90; 90a) from the collapsed state to the rounded state, and inside the folded replacement pipe (10; 10a). Limiting means (32, 34, 46, 48; 222) installed at the inlet end of the replacement pipe (10; 10a) to allow the heated fluid to pass through the full length of the folded replacement pipe to increase the internal pressure of the And pressurizing means comprising means (38, 40, 42, 44; 176, 188) for supplying heated fluid from the trailing end of said replacement pipe (10; 10a) into the pipe (10; 10a). Installation device of the replacement pipe, characterized in that. 9. The thermoplastic replacement pipe (10) according to claim 8, wherein the thermoplastic replacement pipe (10) can be folded flat and manufactured in a collapsed state and expanded in a predetermined rounded state, whereby the replacement pipe (10) maintains the memory in the collapsed state. How to feature. 9. The tube according to claim 8, wherein the pressing means is a flexible and non-elastic material that is closed at the front end 225 and is located within the outer canvas tube 224 and the outer tube 224 and rounds the outer tube under fluid pressure. A resilient tubular inner tube 228 expandable to form a shape, and connecting means located at the rear end of the inner tube 228 for connecting the interior of the inner tube 228 to a hydraulic source ( 230,232,234). 9. The reduced shape of the replacement pipe (10) is folded along its length so that one round and convex portion (82) is formed at one side and interconnected to the round and convex portion (82). And a cross section in which second leg portions 83 and 84 are formed, and the first and second leg portions 83 and 84 are rounded and convex free forming fluid passages 86 and 88 along the length of the folded pipe. Ends at ends 85 and 87, one of the first and second leg portions 83 and 84 is longer than the other, so that the convex ends of the short leg portions overlap one another behind the convex ends of the long leg portions. How to feature. Method according to claim 1, characterized in that the replacement pipe (10, 10a; 80) is made of polyvinyl chloride. 9. A heating device (152) according to claim 8, characterized in that it comprises heating means (152) for heating the end of the replacement pipe (10) to a flexible state to facilitate the insertion of the end plugs (32; 176) that restrict fluid flow. Device. In a method for removing a certain length of a rigid thermoplastic replacement pipe 10 installed in an existing pipeline and manufactured in a reduced shape of the entire diameter to maintain a memory for the reduced shape of the entire diameter, the replacement pipe ( The replacement pipe in the existing pipeline 14, 70, 90, 90a such that 10 returns at least partially in a reduced form with a size less than or equal to the inner diameter of the existing pipeline 14, 70, 90, 90a. Heating (10) to a temperature at which flexible; Removing the replacement pipe 10 in at least partially reduced form from the existing pipelines 14, 70, 90, 90 a while maintaining the replacement pipe 10 in a heated flexible state. Removal method of replacement pipe.

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