FI94283B - Replacement pipe product, method and apparatus for its manufacture and method and apparatus for installing the replacement pipe in an existing underground pipeline - Google Patents

Description

94283

The invention relates to a replacement pipe product, a method and an apparatus for its manufacture and to improvements in methods and apparatus for installing a part of a replacement pipeline in an existing underground pipeline, such as a pipeline in need of repair or replacement. In particular, the invention relates to the installation of a replacement pipeline section within house sewers connected at an angle to main sewers, other side-joining pipelines connected to main pipelines, inside pipeline sections which may have bends and steep bends, and further inside other pipeline sections. related to house drains, side-conveying supply lines that would be difficult to locate after a new pipeline section is installed inside an existing pipeline section.

Various methods and equipment for repairing underground pipelines, such as sewers and the like, have been proposed to allow existing piping to remain in place in the ground, by installing a flexible plastic film or inner tube 2b inside an existing pipe, or by inserting a new plastic pipe into an existing pipe.

In a known process, the pipes are lined with a flexible plastic such as polyethylene. According to said process, the inner pipe is installed from the feed openings 30 at intervals along the pipeline, which makes the process expensive.

According to another process, disclosed, e.g., in U.S. Patents 3,927,164 and 4,064,211, the flexible pipe is inverted after being inflated and blown into a portion of the pipeline at one end thereof. This process is 2,94283 expensive because it requires special equipment, expensive heating, and expensive materials.

The above processes and most others use a flexible or semi-flexible inner tube that cannot withstand appreciable external hydrostatic or ground pressures. Thus, the existing pipe cannot be repaired properly, because if any part of it breaks, the inner pipe may possibly pile up at any pressure, such as a pressure exceeding about 0.28 kp / cm 2.

Both Thomas et al., U.S. Patent 4,394,202 and Harper et al., U.S. Patent 2,794,758, also disclose the insertion of a flexible tube into an existing pipeline to act as an inner membrane in said tube. Thomas presents 15 methods for attaching a flexible wire to an existing wire using an expandable short portion of adhesive-coated rigid plastic. Both the Thomas and Harper processes have the same disadvantages as the above processes compared to other previously known processes 20 which use a flexible diaphragm material so that they do not have sufficient ring strength to withstand external ground and hydraulic pressures. Others have suggested pushing a rigid pipe into an existing pipeline to be repaired. For example, in published GB-25 patent application 2,084,686, an oversized rigid plastic pipe is flattened or otherwise reduced at the workplace and then cold and rigidly inserted into an existing pipe through a large trench through an inspection port. After insertion, the plastic tube is expanded using heat and internal pressure. The plastic pipe will be expanded there. against the existing pipe.

According to GB patent 1,580,438, an existing underground pipe is lined with a plastic inner pipe made of, for example, polyethylene or polypropylene with a memory for plastic. Inner tube

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94283 3 is made in a non-circular U-shape to fit the existing pipe, then inserted in a non-circular form into the existing pipe and then again expanded against the existing pipe in heat and pressure to become 5 round.

Published EPC patent application 0 000 576 discloses that the inside of a semi-rigid plastic pipe is fed into an existing pipe. The semi-rigid plastic tube has sufficient ring strength to withstand all or at least some of the external pressures that may be applied to it.

Most of the above and other known processes using a rigid or semi-rigid pipe for insertion into an existing underground pipe have one common drawback: due to their rigidity or semi-rigidity, they have to be inserted into straight or almost straight existing pipes. This means, for example, in relation to underground sewer pipes, that such known processes are limited to being used in sewer pipes, as they usually have straight pipe sections between the inspection openings.

Most, if not all, such known processes are not suitable for repairing many house drains that extend from the main sewer to the buildings. Often, such side-joining wires have bends or bends in which a rigid or semi-rigid plastic pipe does not yield. Such side-to-side wires are not normally accessible at either end of the inspection openings, and therefore prior art methods of installing an inner tube or repair tube that require an inspection opening or other access at each end are prohibitively expensive. When installing most known underground replacement pipes, large excavations must be made at the end of the connecting pipe to be re-piped or repaired to make room for the insertion of a straight, rigid plastic replacement pipe. When such a large excavation is adjacent to building 94283 4 when connecting a side-joining pipe or at another end where the connecting pipe joins the main pipe, the solution is often impractical and usually expensive.

Furthermore, most of the previously known processes for renewing or repairing the inner pipes of existing underground pipes require access to the part of the pipeline to be repaired from each end of said part. This is not possible in the case of a connecting pipe which, by its very nature, is connected to the mains pipe at a point 10 which is not normally accessible from the inspection opening.

For the reasons explained above, the previously known underground pipeline inner piping and repair processes are simply not applicable to house sewers.

15 Another disadvantage of using known repair and interior piping processes for existing pipe sections involving domestic sewer lines using straight, rigid or semi-rigid pipes is that when the pipes are in place in the existing pipeline section-20, it is very difficult to locate the precise points where the side-joining pipes join the main pipe so that access openings to the exchange pipes can be cut to access the side-coming pipes. This is especially true if the replacement pipe is thick enough and therefore has sufficient tire strength to withstand the typical hydraulic and ground pressures itself.

For the reasons set out above, there is a need for improved methods, equipment and tools to repair existing underground pipeline sections, and especially when house drains and other pipeline sections have bends and curved sections of pipeline that cannot be easily accessed by a repairable section of pipeline. from either end.

Thus, the main objects of the invention are to provide the following: 94283 5 1. A new and improved replacement pipe product for installation in an existing underground line which is particularly suitable for use in repairing and replacing existing non-straight house sewers 5 and when power lines are cross-connected to house drains ; 2. A new and improved method of manufacturing a repair and replacement pipeline product that is particularly suitable for installation in underground lines that are not straight or are connected by side connection lines.

10 3. Method of installing a new or replacement pipe piece in an existing underground line, and in particular one that is not straight or cross-connected to the domestic sewers.

4. Apparatus and equipment for making a replacement piping product-15 as described above.

5. Apparatus and equipment for installing the pipeline product as described above in an existing underground line, and in particular in a line that is not straight or joins the side connection lines; and 20 6. Apparatus and equipment for repairing a new thermoplastic or replacement pipe section installed in an existing underground pipeline, and in particular a house drain, after the new or replacement pipe section is installed in pleated form, by reshaping it into a permanent rounded shape within the existing pipeline.

The set objects are achieved by an exchange tube product characterized by the features of the characterizing part of claim 1; a method and apparatus for manufacturing an exchange tube product, characterized by the features of the characterizing part of claims 5 and 12; . and a method and apparatus for installing a replacement pipe, characterized by the features of the characterizing part of claims 15 and 22.

The invention is a new and improved repair and replacement pipe product, particularly suitable for installation in an existing 94283 6 underground pipeline, such as a house sewer with bends and bends, and a series of closely related methods, apparatus and means for making said product, 5 wire, whether straight or curved, and to reshape said product into a rounded shape after being inserted in a folded, pleated form into an existing wire. The product, processes, apparatus and instruments of the invention are particularly intended for use in installing the product in house drains and other existing underground conduits accessible only from one end of the conduit or having bends or bends or associated side supply conduits.

According to one aspect of the invention, the exchange tube product is a thermoplastic plastic material such as PVC that is first extruded and shaped into a unique pleated and flattened shape so that it retains its pleated memory when reheated so that it can be wound on a roll for storage and use. , so that its cross-sectional size is very small so that it can be easily inserted into an existing underground line, so that it can be inserted into deep pipelines through excavation holes, cleaning holes or other vertical holes without excavation or damage to plastic material, and blade « around the bends and so that, despite its flattened shape, the hot liquid can be passed through it to reheat it along its entire length.

According to another aspect of the invention, the above-mentioned molded lever product is mounted on an existing curved side pipe, for example by reheating the plastic pipe to a flexible state, then pulling the hot, flexible, pleated plastic pipe into an existing side supply line with a traction cable and either a pulley head. and 94283 7 to the main line junction or with a cable winch from the nearest inspection opening in the main line. The pleated, installed tube is then heated along its entire length by passing hot liquid through it, sealing it or restricting its front end, and spraying pressurized such air at one end to reshape and expand the tube into a rounded shape. Then, by continuing to apply internal pressure to the reshaped rounded tube, it is allowed to cool and thus stabilize in its rounded shape.

According to another aspect of the invention, there are various devices for closing or restricting the front end of a plastic tube so as to cause hot liquid to pass through it when it is pleated, and further to allow the pleated tube to expand and reshape into a round shape by applying internal liquid pressure.

According to another aspect of the invention, there is provided a device for closing and sealing the inlet end of a pleated pipe in order to obtain an internal liquid pressure in the pleated pipe when it is supplied to existing underground piping.

According to another aspect of the invention, the device includes a unique pulley-cable device that can be inserted through the supply line into its corner connection with the main pipe and temporarily anchored there by maintaining tension at each end of the cable. The other end of the cable is anchored to the front end of the pleated pipe to be installed; then the opposite end of the cable is pulled to pull the pleated plastic tube into the existing supply side tube with the plastic tube in a heated flexible state.

According to another aspect of the invention, the apparatus includes various means for heating opposite ends of the plastic tubular product and various other portions so as to cause selected portions of the tube to re-press, insert plugs or make the entire length of the tube 94283 8 flexible enough to be inserted into such an existing conduit. , which is not straight.

The above and other objects, features and advantages of the invention will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings.

Figure 1 is a cross-sectional view of a conventional thermoplastic pipe, such as a PVC pipe, used in accordance with the invention in its expanded rounded form; Figure 2 is a perspective view of the thermoplastic tube of Figure 1 and an apparatus for reducing the tube from its circular state to a folded and pleated state for storage on a reel;

Fig. 3 is a cross-sectional view of the thermoplastic tube of Fig. 2 after it has been folded folded along line 3-3 of Fig. 3;

Fig. 4 is a schematic view showing a process of installing the pleated and coil-wrapped thermoplastic pipe of Figs. 2 and 3 within a sewer main pipe from a inspection hole, which pleated thermoplastic pipe is stored on a roll and reheated during installation in an underground pipe;

Fig. 5 is a schematic cross-sectional view showing a detail of an apparatus for expanding a pleated ter-moplastic tube according to Figs. 2 and 3 and rounding after being inserted into the bulk main tube as shown in Fig. 4.

Fig. 6 is a schematic cross-sectional view showing an alternative structure for expanding and rounding a pleated thermoplastic tube after it has been inserted into an existing conduit; *

Fig. 7 is a schematic cross-sectional view of a typical house sewer extending from a building to a connected main sewer line and illustrating a method of installing a thermoplastic pipe 35 in an existing house sewer in accordance with the invention; 94283 9

Figure 8 is a cross-sectional view of a preferred form of the thermoplastic tube of Figure 1 when pleated for installation in an existing underground conduit;

Fig. 9 is a schematic side view of an apparatus for manufacturing the thermoplastic tube of Fig. 1 in a pleated form according to Fig. 8;

Fig. 10 is an enlarged side view of the calibration device of the apparatus of Fig. 9 for use in making a thermoplastic tube in the form shown in Fig. 8; Fig. 11 is a side view of one calibration plate of the calibration device of Fig. 10 taken along line 11-11 of Fig. 10;

Fig. 12 is a plan view of a pleated end portion of the thermoplastic tube of Fig. 8 having a gripping device attached to pull the tube into an existing conduit and shrink the tube end to allow internal pressurization of the tube for expansion;

Fig. 13 is a sectional view taken along line 13-13 of Fig. 20;

Fig. 14 is a somewhat schematic plan view of a cable-pulley apparatus according to the invention, also shown in Fig. 7, for the purpose of drawing the pleated thermoplastic tube of Fig. 8 to a connecting line, which device is shown in its operating position; Fig. 15 is a view similar to Fig. 14, but the apparatus of Fig. 14 in a collapsed form ready to be inserted into the access line;

Fig. 16 is a roughly schematic vertical view of the apparatus of Figs. 14 and 15;

Fig. 17 is a vertical side view of a closure means for plugging an end of a length of the thermoplastic tube shown in Fig. 8 after said end has been made round, for use in supplying liquid, heat and liquid pressure into the thermoplastic tube.

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Fig. 18 is a vertical side view of the front end of the tool of Fig. 17;

Fig. 19 is a view 5 of the end of the thermoplastic tube shown in Figs. 17 and 18 with a closure means inserted into the tube and pressed into place by a chain pressing device?

Fig. 20 is a view of the chain press apparatus of Fig. 19 prior to mounting on the tube and plug of Fig. 19; Fig. 21 is a cross-sectional view taken along line 21-21 of Fig. 21 showing the chain pressing apparatus of Figs. 19 and 20 which compresses the end of a thermoplastic tube into the closure device shown in Figs. 17-19;

Fig. 22 is a somewhat schematic longitudinal sectional view across the front end of the thermoplastic tube of Fig. 8 with the end press of Figs. 12 and 13 attached to the end of the tube with the end of the tube expanded and rounded and the cutting tool fed to the rounded tube according to the invention; a section to cut the compressed end from the rest of the pipe;

Fig. 23 is a sectional view of the tube and cutting tool of Fig. 22 taken along line 23-23 of Fig. 22; Fig. 24 is a roughly schematic vertical side view of an end heater used to heat an end portion of a thermoplastic tube to reshape the end portion, the heating means shown mounted on the pleated end portion of the thermoplastic tube of Fig. 8;

Fig. 25 is a perspective view of an expandable head closure used to close or contract the end portion of a thermoplastic tube instead of the end press of Figs. 12 and 13 to allow expansion and rounding of the pleated thermoplastic tube; 94283 11

Fig. 26 is a front elevated side view, partially in section, of the expandable tube of Fig. 25;

Fig. 27 is a schematic diagram showing the installation of the expandable closure device 5 of Figs. 25 and 26 in a thermoplastic tube in an expanded and rounded form;

Fig. 28 is a schematic view similar to Fig. 27 but showing the tube of Fig. 27 after refolding with the expandable plug 10 in an internally unexpanded form;

Fig. 30 is a schematic view showing another use of the expandable closure device of Figs. 25 and 26;

Fig. 31 is a schematic diagram further showing the use of the expandable closure of Figs. 25 and 26 according to the process shown in Fig. 30;

Fig. 32 is a schematic diagram showing yet another use of the expandable closure tool of Figs. 25 and 26 for expanding and rounding a pleated thermoplastic tube after it has been fed into an existing underground conduit;

Fig. 33 is a schematic view of a main pipe section and an expandable cross-connect pipe connecting to it, illustrating an alternative method of drawing the thermoplastic pipe of Fig. 25 8 into the pipe to be repaired;

Fig. 34 is a schematic view of the end portion of the pleated thermoplastic tube of Fig. 8 illustrating a method of disconnecting a traction cable from the front end of a tube after it has been inserted into an underground conduit;

Fig. 35 is a schematic diagram similar to Fig. 34 illustrating yet another method of disconnecting a traction cable from a thermoplastic pipeline after it has been inserted into an existing underground pipeline; Fig. 36 is a cross-sectional view of the corner junction of the main pipeline and the side-connected pipeline to its ice when the thermoplastic pipe of Fig. 8 is installed and expanded within the main pipeline to be repaired, and illustrating and the main pipeline;

Fig. 37 is a schematic vertical side view illustrating a method and apparatus for folding a thermoplastic tube made round to be inserted into an existing underground conduit; Figs. 38A to E are schematic sectional views taken along lines 38A-38A through 38E-38E, respectively, in Figs. 37;

Fig. 39 is a somewhat schematic vertical side view of a detachable end clamp attached to a traction cable and detachment line for use in crimping the front end of the pleated tube of Fig. 8 during installation;

Fig. 40 is a top plan view of the end press of Fig. 39; and Fig. 41 is a top plan view of the release wedge portion of Fig. 39.

Referring first to Figure 1, the number 10 refers to a type of pipe used to rebuild, repair or replace underground pipeline sections 25, such as sewer pipes or the like, in accordance with the present invention. One characteristic of the pipe is that it is made of a thermoplastic material such as PVC and more particularly of a material that is normally rigid and thick-walled so that it has sufficient ring strength to withstand external ground and hydraulic pressures that may be applied to it underground. However, such a thermoplastic pipe can be made flexible by heating to e.g. 93 ° C or higher when using a PVC pipe. The tube 10 35 is characterized in that it is structurally rigid at typical ambient surface or subterranean temperatures, but becomes flexible and can be machined into various shapes when heated or reheated. Another characteristic feature of such a thermoplastic material is that it has 5 memories; that is, if it is made into a certain shape such as a rounded tubular shape and then subsequently heated and flattened or pleated and then cooled to maintain its permanently pleated shape and then heated without contractions, it tends to return to its original rounded tubular shape. Conversely, if the tube is initially initially formed into, e.g., a collapsible and pleated shape, as shown, for example, in Figures 3 and 8, and then subsequently heated and expanded by internal pressure to a rounded shape and then cooled and permanently rounded, it tends to return to its original pleated shape. , if it is then reheated without shrinking. This memory aspect of the thermoplastic tube is used to advantage in certain aspects of the present invention.

One conventional and readily available type of pipe useful in the practice of the present invention is polyvinyl chloride (PVC) pipe with standard dimensions (outer diameter / wall thickness) 25 in the range of 13 to 65 currently available for underground pipelines such as drainage pipes, water pipes, etc.

Although in the most preferred embodiment of the present invention, the thermoplastic tube is manufactured in a wetted form, as shown in Figure 8 of the figures. 9-11, at least certain aspects of the invention may also be embodied using a thermoplastic tube made in a tubular or rounded shape. Figure 2 illustrates an apparatus 11 for reshaping a conventional PVC pipe 10 made round. Figure 3 illustrates a cross-section of a tube 94283 14 after being reshaped by flattening and pleating using the apparatus shown in Figure 2. The PVC pipes are furthermore specially heated in any conventional manner, such as by a heating device 11a, which may be a thermostatically controlled steam box or a housing with thermostatically controlled electric heating elements. By passing the original circular tube 10 through the heat box 11a, the tube is heated to a temperature sufficient to make the tube flexible. Sit-10 is then flattened or preferably pleated in a creasing device 11 to reduce its entire cross-sectional dimension so that it can be easily drawn into an underground pipe having the same or only slightly larger inner diameter than the original outer diameter of the thermoplastic pipe. A smaller sized pleated thermoplastic tube is shown at 10a in Figure 3.

Although the unit shown in Figure 2 schematically illustrates a pipe folding apparatus, a practical pipe folding apparatus and method are shown in detail in the apparatus of Figures 37 and 38A-E. It can be seen that after passing through the heater 11a, the circular tube 10 is first flattened by an opposing pair of flattening rollers 60, 61 and then passed under a folding wheel 62, progressively supported by three different folding roller rolls 63, 64, 65. The folding roller pairs 63 are arranged to co-operate 62 to start folding the tube 10 into a U-shape. All three folding rollers 64 then continue the folding process by being arranged in a semi-U-shape to cooperate with the folding wheel 62. Finally, four children. the set of wetting roll 65 is arranged in a U-shape to cooperate with the folding wheel 65 to complete the folding of the tube 10 in a U-shape. The pleated tube is then passed through a compression mold 66 while cooled to keep the tube in its U-shape so that it has a U-shaped memory. The tube folded from the mold 66 can 94283 15 either be stored in a predetermined length or taken directly to the steam tube for reheating and made flexible so that it can be inserted directly into an existing tube.

5 Alternatively, after the flattening process and before folding, the tube may be wound on a roll in its flat state in the heat box 18 shown in Figure 4. The smooth, rolled tube may then be reheated in a heat box at the workplace and then drawn from the heat box and folded as described above. tube.

In some applications, it is also possible to install a thermoplastic pipe in an existing pipe in flattened form, especially when the thermoplastic pipe 15 in its rounded form is considerably smaller in outer diameter than the inner diameter of the pipeline to be repaired. However, in most circumstances, it is more preferred that the thermoplastic pipe be installed in the existing pipeline in a longitudinally pleated form as shown in either Figure 3, Figure 8 or Figure 38E. Of all the pleated shapes, the one shown in Figure 8 is the most preferred for the reasons explained above.

As mentioned above, a thermoplastic tube, when made in a round shape, has a memory that tends to restore it to a round shape when it is reheated after folding. Thus, if it is necessary to reheat said pleated pipe to make it flexible for installation in an existing pipeline, the pipe will tend to return to its circular shape 30, perhaps prematurely, unless restricted. En-. For all this reason, it is advantageous to produce the thermoplastic tube primarily in the desired pleated shape. Then, when the pleated tube is reheated to make it flexible to be inserted into an existing pipeline, the tube takes back its pleated shape until it is completely inserted into the existing pipeline 94283 16 and ready to be reshaped into a circular shape.

Regardless of whether the thermoplastic tube is made round or pleated, the tube should be in a bottom-5 moistened form when it is ready to be inserted into an existing tube. It is also preferred that the thermoplastic tube can be wound on a roll when heated and thus made flexible in a storage disc such as the coil 12 shown in Fig. 4.

The coil 12 of the pleated thermoplastic tube is stored in a housing or "heat box" 18 having a thermostatically controlled heater 24 to heat the inside of the heat box, and the pleated tubular material 10a of the coil 12 is made flexible if desired. The heat box 18 15 preferably also has an air circulation system 19 to prevent heat from accumulating inside the heat box, thus ensuring that the coil 12 of the pleated tube is heated evenly. The heat box 18 is preferably mounted for transport and is shown positioned on a flat 20 platform of a truck 20 for transport to a work site. The smaller heat box can be equipped with wheels and transported by hand for use in the maintenance of small hard-to-reach pipelines such as house drains. In either case, either a machine or a manual device exists to rotate the spool 25 12, to wind the material on or off the spool. The heating plate 18 is provided with a door 21 and may also have a downcomer funnel 22 and a roller 23 to facilitate the supply of a pleated thermoplastic pipe to the underground piping through a vertical inlet such as the existing main drain 14 inspection port 16.

. According to one aspect of the invention, the heat box 18 is transported to an opening at the workplace, such as an inspection opening 16, to an underground pipe body to be repaired, such as a main drain 14. The end of the reduced pipe 35a is connected to a traction line 26 obtained from an opening near an existing pipeline, such as another inspection opening 94283 17 (not shown), and connected by an end clamp 28 to the free or front end of the new pipe. The new pipe is made flexible by the heating coil 12 in the heat box 18 by the heating device 24. The drive line 26 is operated by a winch in the next inspection opening downstream of the inspection opening 16 to pull the flexible pleated pipe 10a from the coil 12 through the supply pipe 22 and around the supply pipe roll 23 and to the next inspection opening. After the new tube is pleated, it is heated and expanded into a round or substantially round shape to obtain a tube that cures into a thick-walled rigid shape with sufficient ring strength to withstand external hydraulic and ground pressures.

Figure 5 illustrates one way to expand a reduced size pipe after it has been drawn into the original pipe for re-installation or replacement. According to this method, a pair of plugs 30 and 32 are inserted into opposite ends of the pleated tube when at least 20 of said ends are in a heated flexible state. The plug 30 is installed at the rear end of a new pipe section located at the inlet end of an existing pipeline. The plug 32 is installed at the front end of the new pipe, i.e. at the end of the traction line, after disconnecting the pipe line. Each of the plugs 30 and 32 t 25 has edge-expanding sealing members 34 arranged to act as a removable locking fitting with the original tube 14 and the new tube 10a. The sealing members 34 are expanded through pressure lines 36, such as air pressure lines, which lead to an above-ground control device (not shown). The plug 30 has an inlet line 38 therethrough to introduce an expansion agent such as real 9 steam or hot water into a new pipe. Such a pipe has a suitable control valve 40 as well as a pressure gauge 42 and a backup valve 44. The plug 32 has an outlet line 46 in communication with the area between said two plugs 35 and suitably has a valve at 48.

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The newly installed pleated pipe, with plugs inserted at its opposite ends, is heated internally by passing the right steam through the small passages in the folds of the new pipe, shown in Figure 8.

5 The (downstream) valve 48 at the lower end is open, so that the entire length of the new pipe is heated. The valve 48 is then closed, while instead the pressurized steam continues to pass through the plug 30 to pressurize the pleated tube and cause it to deform and expand into a rounded shape 10. If the new tube is made of pleated, it should be cooled or allowed to cool after it has taken on its round shape while maintaining its internal pressure, such as cold air pressure, so that the tube settles into its round shape. Said last step is not necessary if the pipe is made in a round shape, unless the pipe is expanded or extended beyond its original diameter in the reshaping step.

Unless the pleated new tube has internal passages, as may be the case when the new tube 20 is pleated completely flat, as shown in Figure 3, the new tube should be heated from the outside such as by passing steam through the existing tube before inserting plugs 30 and 32 into the new tube. ends. Then when the new pipe is heated the whole pi-. 25, the plugs 30 and 32 can be easily inserted at opposite ends thereof, the valve 48 would be closed and steam or hot water would be passed through the plug 30 to expand the pleated tube and reshape it into a round shape.

Fig. 6 shows an extension of another type of device 35. to reduce the size of the tube. Such a device includes a mandrel 50 with a heating device 52 inside which is capable of heating the new tube flexibly. The mandrel 52 is connected to a traction cable 54 or other device by which it 35 can be routed through the original tube. After proper heating of the mandrel and using tension in the traction cable 94283 19 the mandrel is pulled through the original pipe so that the new pipe expands to the desired diameter. Obviously, with this method, the traction cable 54 could be inserted into the new pipe before the new pipe is pleated to be inserted into the existing pipeline.

A third heating method for rounding and expanding a new pipe involves flushing hot water or steam along an existing pipe to be repaired next to a pipe already installed in parallel but still pleated until the desired temperature at the lower end is reached. The new tube is then pressurized with hot water or steam and expanded under pressure to a round shape and diameter to the desired extent.

In a particular pipe reconstruction process, a conventional PVC pipe is obtained which has an outer diameter of 12.7 mm more or less than the inner diameter of the pipe to be renewed. The PVC pipe has standard wall thickness ratios with respect to the outer diameter, as shown above. The PVC pipes are heated to at least 93-99 ° C and reduced to the shape shown in Figure 3, Figure 8 or Figure 38E. The pleated pipe is then stored on large coils so that it can be transported by truck to the workplace. When installed in an existing underground pipe or line, the new pipe is reheated, preferably in a heat box 18, so that it is flexible and can be easily pulled generally vertically downwards through a deep inspection opening and then generally horizontally through the existing line. Once installed in said existing pipe section 30, the pleated pipe is closed, capped, heated and rounded. If desired, it can also be expanded beyond the original or designed rounded diameter to fit snugly against an existing piping piece.

The advantage of extending a newly installed thermoplastic pipe beyond the diameter of its original structure is shown in Figure 36, in which an existing section of pipeline to be repaired is connected at an angle to at least one domestic sewer or other connecting pipe. In Fig. 36, the main pipeline 70 is cross-connected at 72 to a connecting line 74 such as a house sewer line. When a new thermoplastic tube is installed in the main tube 70 and rounded and expanded or extended beyond the diameter of its original structure so as to tightly contact the inner wall of the existing main tube 70, a protrusion or bulge 76 is formed in the opening or junction 72 of the connecting tube and main tube 70. Actually said the protrusion 76 indicates the exact location of the opening into the main pipe of the connecting pipe. By passing the television camera through the main tube, the exact location of said protrusion or bulge 15 and thus the opening of the connecting tube can be determined. The remote cutter 78 can then be routed along the main tube to the exact location of the protrusion and can be used to cut the protrusion 76 from the new tube 80, thereby reopening the access tube 74 to the main tube.

20 Rounding and expansion or stretching of a newly installed thermoplastic tube is accomplished by the methods described above or by the methods described below in connection with further embodiments.

Although the flattened and pleated thermoplastic tubes of Figures 3 and 38E are suitable for use in the installation processes described above, a preferred form of such a pleated tube 10 is shown in Figure 8. The thermoplastic tube 10 of Figure 8 is made substantially in said pleated form. It is a generally collapsible tube folded along a generally curved spherical longitudinal pleat 82 into a pair of overlapping arms including a long arm 83 and a shorter arm 84. The long arm 83 terminates in a curved or spherical free end 85 so as to form a small 35 through a pleated tube of longitudinal passage 86. The shorter arm 84 also terminates in a curved or spherical free end 94283 21 which also forms a longitudinal passage 88 through the tube. In addition, the lightly pleated portion 82 forms a passage 89 along the inside of the pleat from one end of the tube to the other.

The spherical pleat and stem ends described above are important because they prevent the pleated portions of the pipe from cracking when folded, which could otherwise occur if the pipe is pleated as shown in Figure 3, especially if the pipe walls are thick. Lines-10 Ages 86,87 and 89 are also important because steam or other hot liquid can pass through the fully pleated pipe to reheat it and thus reshape it after the pleated pipe is installed in an existing underground line. Without such access to the interior of the pleats, reheating would be a long, slow process and very difficult to accomplish.

The pleated shape of the pipe of Fig. 8 is particularly suitable for use as a replacement pipe for repairing sewers, such as the sewer pipe 90 shown in Fig. 7, leading from because of tea. Firstly, such connecting pipes have difficult • access problems because they are often under grass, trees and shrubs and thus cannot be accessed from the inspection openings. Digging up the connecting pipe for repair would therefore become very expensive. When inserting a new access pipe into the existing underground connection pipe, access to it is usually only possible from a single small vertical excavation near the building, as shown at 98 in Figure 7. Such a trench has little space for 35 operations or large installations. .

22 94283

Second, the drains of houses are usually much smaller in diameter than the main pipes and often have sharp bends or bends, unlike the main pipes, which are usually straight from the inspection opening 5 to the inspection opening. For example, the house drain 90 has a bend at 100, which makes it impossible to insert a straight rigid pipe into an existing side pipe. In Figure 7, the house drain 90, accessed from the vertical trench 98 adjacent to the building 96, extends 10 below the lawn 102 into the main pipe 94 at a considerable depth below the street 104. The processes and devices described below are particularly suitable for solving the specific problems of installing a replacement side pipe in an existing underground side pipe from a single small, usually vertical, access opening. Such methods and devices utilize the fabricated form of the pleated thermoplastic tube shown in Figure 8.

Referring to Figures 9, 10 and 11, the pleated thermoplastic tube of Figure 8 is fabricated using a conventional plastic tube nozzle 106 to protrude into a vacuum box 108. to its steam tube 114 25 for reheating to a flexible shape so that the resulting pleated tube can be turned in its pleated form to a storage coil 116, which would typically be located in the heat box 18 of Figure 4.

Nozzle 118 and pin 120 are located at the outlet of the nozzle out-30. A gap 121 of about 30.5 to 35.5 cm is between the lower end of the nozzle 118 and the inlet of the vacuum box 198.

The vacuum box is divided internally by partitions 122, 123 into three parts. All three sections are filled with water-35 inside the box up to level 124. The first of the box

Il. »Il.4 l.lil I I J 41 · I

94283 23 i.e. the top is connected to a vacuum source 125. Although the entire vacuum box is under negative pressure due to its connection, the top of the box has the highest possible negative pressure. The calibration device 126 is in the first part of the vacuum box 5. The calibrator shapes and maintains the extruded plastic material in the desired pleated form as the material cools and cures as a result. The water inside the vacuum box acts as a cooler and the vacuum fed to the box cooperates with the calibration device 10 to maintain the plastic material in its desired pleated form until it is able to freely retain said shape by cooling. With particular reference to Figures 10 and 11, the calibration device includes a series of calibration plates 128 arranged spaced apart and assembled together by connecting rods 130 and spaced between the plates on the rods of insulators 132. The rods are helically threaded at both ends and secured with nuts 134. Calibration plates 128 closer to the inlet-20 end of the calibrator are closer to each other than those lower due to the greater flexibility and flowability of the plastic at the inlet end and therefore need to maintain the nozzle shape in the calibrator. The calibration device optionally includes a central tube 136 with its nozzle 25 to convey cooling water to and between the plates to cool the plastic more rapidly. Referring to each calibration plate 128 of Figure 11, there is a precisely cut cutting opening 138 and an external size of the pleated tube that is shaped and maintained in the calibration plates. Each plate 128 of the calibration device is exactly the same size and has an opening of the same shape. Comparing Figures 8 and 11, it can be seen that the opening 138 of the calibration plate includes a short arm 138a corresponding to the short arm 84 of the pleated tube 84 and a long arm 138b corresponding to the long arm 83 of the tube, as well as a rounded portion 24c from fold 82.

In making the tube of Figure 8, a raw plastic composition such as polyvinyl chloride is fed to nozzle 106 through feed tube 107 where the material is heated to a high temperature, e.g., 182 ° C, and then pressed through nozzle 118 where very hot plastic material meets pin 120. Nozzle and pin are thus dimensioned that they shape the plastic tube into the desired final size and shape. The plastic material is fed through the opening 121 into the first part of the vacuum box 120 and through the calibration plates. The plates form and maintain the plastic material in the size and shape determined by the openings 138 in the calibration plates.

When the plastic material first enters the calibrator, it is very hot and quite fluid, and therefore the calibration plates 128 are very close together at this point so that the desired shape can be maintained. The vacuum inside the box holds the plastic against the outer edge of the opening 138 as the cooling water cools the plastic material. If desired, the compressed air injected from the source 140 into the pin 120 may be conveyed down through the inner passages 86, 88, 89 of the pleated plastic mold to ensure that the plastic does not completely accumulate and to maintain the tubular shape of the pleated tube 25. By the time the plastic material enters the lower end of the calibration device 126, it has substantially cooled and is able to retain its own shape under the tension provided by the traction rollers 110. Such rollers pull the pleated plastic from the vacuum box as a continuous strip. From the calibration plates, the strip passes through the second and third chambers of the vacuum box, where it gradually hardens. By the time the strip 10 exits the vacuum box, it is cooled, rigid, and substantially in the form shown in Figure 8. The puller 110, which pulls the tensioned strip or stream of material from the nozzle, adjusts the wall thickness and other dimensions of the pleated tube.

The pleated strip from the puller 110 is fed through a steam pipe 114, where the steam source 115 is fed through an inlet 5 117 to reheat the strip to a flexible state so that it can be wound on a storage coil 116.

The number of plates in the calibrator and the spacing between them are a function of the extrusion rate determined by the puller and the desired wall thickness of the final tube.

As mentioned above, the coil 116 of the stored folded tube 10 can be placed in the heat box 18 as shown in Figure 4 for transport and use at the workplace.

Figure 7 illustrates not only the sewer connection pipe as described above, but also the method, apparatus and tools for inserting the pleated thermoplastic pipe according to Figure 8 into the connection pipe. First, a vertical trench 98 must be excavated, preferably as close to the house 96 to which the access pipe 90 is connected as possible to pass through 20 and gain access to the existing access pipe 90.

The length of the connecting pipe to be repaired or replaced can then be determined by inserting a flexible fiberglass rod into the connecting pipe from the trench and feeding the rod through the connecting pipe until it joins the main pipe 94. At this angle, the length of the rod inside the connecting pipe can be marked and measure the length of the plastic tube 10 required for the task. When the lengths of the sets of connecting pipes 30 to be repaired are known, the pleated pipe 10 can be cut in advance to correspond to said lengths, either at the factory or at another location far from the workplace. Said pre-cut lengths can then be transported to workplaces for installation.

35 Alternatively, the required lengths can be cut at the workplace from the coil 116 or 12 94283 26 (Figure 4) inside the heat box 18 transported to the workplace. If the trenches for repairable connecting pipes cannot be accessed by the truck 20 on which the heat box 18 is mounted, the length of the plastic pipe 10 tal-5 can be flown with other, smaller coils inside smaller wheeled heat boxes (not shown) which are introduced into said trenches. Figure 7 shows a smaller "mini heat box" 140 including a coil 142 of a pleated tube 10.

Alternatively, instead of measuring and pre-cutting the required lengths of pleated plastic pipe 10 to lengths corresponding to the lengths of the connecting pipes to be repaired, the pleated pipe 10 can simply be heated in a heat box 140 15 and fed into the existing connecting pipe until a new pleated pipe 94 reaches corner joint, and then cut it across the coil.

Similarly, if the pleated plastic tube 10 is cut to a pre-length at the factory, it may be transported in striped lengths of pre-20 to various workplaces and heated there for insertion into an existing connecting tube in a steam tube such as the steam tube 114 shown in Figure 9. The steam tube may be made of metal or of a similar material, the flexible fabric or corresponding ends of which can be tied around a pleated plastic tube to hold steam inside the vapor tube. Such pipes are lightweight and can be easily transported to the workplace and can be six meters long or longer. In field operation, the fabric steam pipe is cheaper than the metal pipe due to its weight.

If the drain pipe is straight and its entry point in the trench is close enough to the surface, or if the trench is large enough, it may be possible to insert a sufficiently long pleated plastic pipe 10 into an existing pipe 35 simply by inserting a new pipe into the existing pipe until the front end meets the main pipe.

94283 27 However, this is often not possible because the new pipe must be able to bend under a bend in the trench or somewhere in the side pipe, or both. Pulling the flexible pleated plastic tube into an existing connecting pipe without reaching the main pipe side end of the connecting pipe has produced particular problems in the present invention.

One method of pushing a new connecting pipe into an existing connecting pipe by pulling involves the use of a pull-10 game, which cable is attached to the front end of the new connecting pipe. The cable runs around the pulley as the connecting pipe joins the main pipe and then goes back to the connecting pipe inlet. By applying traction to the traction cable from the access point-15 in the trench 98, a new pipe can be pulled along the entire length of the existing connecting pipe. This method involves the use of special equipment.

First, the front end of the new connecting pipe must be compressed to reduce the size of the passages 86, 88, 89, as shown in Figure 8, to provide internal pressurization of the pleated pipe after being inserted into the existing connecting pipe while still allowing hot liquid to pass through the pleated pipe. that it can be heated along its entire length and thus obtain an or-25 wooden expansion for rounding. To achieve this limitation and clamping of the head, the head clamping device shown in Figures 12 and 13. A side view of the end press device is also shown in Fig. 22. Referring to said three figures, the end press 144 30 includes a pair of rigid metal plates. The plates include a top plate 145 and an opposite bottom plate 146. Each plate has forwardly extending cam portions 147 extending therethrough. A second pair of aligned holes 149 extends through the bottom and top plates rearwardly from the hole 148 in the cable 35 to receive the crimp bolt 150. The bolt 150 94283 28 also extends through the holes 151 drilled in the same line through the pleated plastic tube 10.

To mount the end press 144 to the front end of the pleated plastic tube 10, the front end of the tube is heated to become flexible, for example in the tube end heater 152 shown in Fig. 24. Said heater 152 includes a thin-walled rigid tube 154 closed at one end by an end plate 157 steam hose connection 158. At the opposite end of the hearing aid is a flexible wrapper 160 of fabric or other suitable material wrapped in the tube 154 at the connection 162. The free end of the wrapper 160 may be tied or wrapped around the pleated plastic tube 10 to allow steam to escape from the wrapper 16. to the pipe through connection 158. The length of the tube 152 may be about 60 cm for most applications, although it may be longer or shorter depending on the application.

After the front end of the tube 10 has been bent, the plates of the end press 144 are attached to the end of the tube and the bolt 150 is inserted through the bolt holes 151 and tightened so that the opposing plates 145, 146 compress the part between the pleated tube flattened to reduce the passages 86, 87. 89 sizes at the 25 ends of the pleated tube. It should be noted that the widths of the compression plates 145, 146 are considerably narrower than the overall width of the pleated tube 10, so that the passages 89 at the pleat and at the long leg end 86 do not engage completely after the compression force 30 applied to the pleated tube. Thus, when compression is used, the liquid can still pass completely from the compressed end of the pipe, but the passages are still small enough that the internal pressure formed inside the pleated pipe can be made to expand and round the pipe.

29 94283

The head heater described above is also useful for other purposes, as will be apparent from the following description.

Another type of end press that can be used in place of the end press 144 is the detachable end press 250 shown in Figures 39-41. The press 144 has the disadvantage that it cannot be removed from the front end of the tube 10 when pushed into a closed tube without cutting off the pressed end of the tube using a special remote 10 the cutting means shown in Figures 22 and 23 and described thereafter. However, the detachable end clamp 250 can be detached from the compressed end of the new pipe, if desired, and pulled from the existing pipe by cable.

The detachable clamp 250 includes an upper jaw portion 252 hinged at 254 to a lower jaw portion 256. The lower jaw portion 256 includes a front end protrusion 258 having a traction cable hole 260 extending therethrough to secure the traction cable 262. The jaws 252, 256 have gripping ends 2063, 264 the front end 266 of the plastic tube 10 and compress it when it is hot and flexible.

The bolt 268 extends through a large opening 270, which is larger than the bolt head 269, and through an in-line smaller bolt opening 272 in the lower jaw 25 256. The bolt hole 272 is smaller than the nut 273 and the end 269 of the bolt 268. The bifurcated, detachable wedge member 276 has two parallel branches 277, 278 forming a slot 280 and connected vertically to the wedge-shaped body 282. Flexible release cable or rope 284 is secured to the body 282 by passing it through a hole 286 in the body. The wedge member 276 is designed to be wedged with arms 277, 278 extending between the end 269 of the bolt 268 and the upper surface of the upper jaw 252, extending below the head and the slot 280 to receive the spindle 94283 30. Thus, the bolt head 269 is pulled against the bifurcated arms 277, 278 rather than through the large upper jaw opening 270 when the bolt is tightened to press the jaw ends 263, 264 against the tube 10.

To disconnect the clamp from the new pipe after the pipe has been pulled into the existing sewer connection pipe using a traction cable 262 and after the new pipe has been rounded except for the crimped end, the disconnection cable 284 is pulled. This pulls the wedge member 10 276 below the bolt head 269 (or nut 273 if the bolt nut end is above the upper jaw), allowing the bolt head to fall through the large opening 270 in the lower jaw 256, thus allowing the jaws to open and remove the pipe end. The wedge member and clamp can be pulled from the side or main tube using their respective pull cables.

Another tool used to pull the new pleated connecting tube into the existing side tube inlet 98 is a pulley cable device, referred to as a "traction frog", as shown in Figures 14-16. The traction frog 152 includes a cable pulley 154 rotatably mounted on the pulley holder 156 157. Mounted on opposite sides of the open rear end of the pulley rack are angled branches 25 158. Each branch has a front end portion 158a and an integral rear end portion 158b.Drawing the trailing ends of the leg 168 are a pair of flexible rear arms 160, to the bracket 156 are spring loads 30 which force the arms outwards as shown in Fig. 14. However, the arms can be turned inwards in the pin to the positions shown in Fig. 15 in order to obtain said arms and thus the whole size. device to pass through the side tube.

A pair of generally triangular arms 164 are connected by a pin joint to the joints of the front and rear leg portions 158a, 158b 94283 31 by a spring loaded pin joint 166. The spring loaded joints 166 force the arms 164 to their extended positions as shown in Figure 14 when normal to the rear leg portions 158b. in their applied positions. However, the arms 164 can pile against the spring pressure into their collapsible position as shown in Figure 15, again allowing the traction frog to pass through the connecting tubes to its destination. A traction cable 168, both ends of which lead back to the inlet 98, is pulled around the pulley 154.

With the traction cable 168 attached, but with both ends of the cable leading back to the inlet 98, the traction frog is inserted into the existing connecting tube 15 and inserted therethrough using a flexible fiberglass push rod (not shown). When the frog reaches the corner joint of the side tube and the main tube and the bracket 156 and associated pulley are inserted into the main tube and the front arms 158a also enter the main tube, the arms 20 164 extend outward from the position shown in Figure 15 to the open position shown in Figure 14. in position, the rear arms 158b and the associated straps 160 press against the inner wall of the existing connection tube. At this point, both ends of the traction cable 25 168 are pulled to firmly anchor the traction frog at the junction of the side and main pipe.

As the traction cable is continued to tension to hold the traction plug in place, the other end of the traction cable is attached to the end clamp 144 (Figures 12-13) or 30 detached from the end clamp 250 (Figures 39-41). The other end of the cable, still in the inlet 98, is pulled by pulling a heated, flexible, pleated plastic tube 10 through the side tube and around the bend 100 until the front end of the pleated tube 10 enters the side tube and main tube 35 with a pull frog 152. Traction can be applied to cable 168 or 94283 32 using a manual or machine-operated winch 170 (Fig. 7) in the inlet 98. Due to the triangular shape of the arms 164, the tensile stress applied to the cable 168 prevents the traction cam from moving up or down.

5 After the new, pleated plastic tube reaches the frog in the main tube, the cable connection at the compression end of the tube is disconnected and the cable end is pulled through the pulley, dropping the draft frog into the main tube. The cable is then pulled from the service tube through the inlet and the frog 10 can be recovered from the main tube later using conventional return methods. At this point, the pleated plastic tube 10 is completely inserted into the connecting tube to be repaired with its compressed front end in the main tube. The pleated plastic tube is now ready to be reheated and expanded into a rounded shape in an existing connection line.

Before discussing the process of expansion and rounding used in connecting pipes, it is worth mentioning. a method and apparatus for disconnecting the traction cable 168 from the main compression 144 so that the cable can be pulled by a traction frog. This can be done in several ways, as shown in Figures 34 and 35, for example.

Figure 34 shows what is referred to as a disconnect cable disconnection. In this method, the "slack" end 168a of the traction cable 168 is attached to a cord or cable 172 that breaks with relatively little force, which in turn is tied at 173 to the front of a strip-folded tube 10 for insertion into an existing connection tube. From the sloping end, the traction cable 168 is loosely pulled 30 through the cable hole 148 in the end press with loose loops 168b, 168c and then pulled through the frog pulley. The cable pull end remains in the side pipe inlet. If the end clamp is not used, the cable hole 148 can be drilled directly through the moistened front end of the plastic tube. As the winch in the inlet pulls the cable through the traction frog to winch the new tube pleated 94283 33 into the existing side tube, the string 172 maintains moderate tension in the water end 168a of the cable. When the front end of the pleated new tube reaches the traction frog, the traction end of the cable jerks violently, cutting the cord 172 and 5, disconnecting the cable end 168a through the cable hole 148 so that the cable can be recovered.

Figure 35 illustrates a similar method of cable disconnection, referred to as manual cable disconnection. In this method, the watery end of the cable 168 is again pulled on the loop twice through the cable hole 148 to the front end of the new tube 10 pleated to form double loops 168b, 168c. The fume hood 168 is then passed through the existing side tube 90 to the traction frog and back to the inlet. The water portion 168a 15 of the cable must be longer than the length of the new pipe 10 to be installed. When the winch pulls a new pipe into the existing connecting pipe, a moderate tension is maintained in the water at the end 168a of the cable, which allows the pleated new pipe to be drawn into the connecting pipe. Once the new pipe 20 has been well inserted into the existing connecting pipe, the loose end 168a of the cable is removed at the inlet end, allowing it to be pulled out of the beginning of the pipe just inserted through the cable opening 148.

Once the pleated new tube is in place within the existing side tube, it is ready to be expanded and rounded to replace the existing side tube as a functional connecting tube. At this point, the front end of the new pleated tube 10 is already shrunk by an end press 144 or 250 so that the pleated tube 30 can be pressurized from the inside with a liquid and still allow hot steam or other liquid to pass through it. This allows the entire inner length of the pleated tube to be heated to be flexible for expansion. At this point, of course, the end 35 of the pleated tube just inserted is covered with a closure, allowing hot steam or other liquid to enter the tube to heat and 94283 34 to expand it. Such a closure device or stopper is shown in Figures 17 to 21.

Generally, a conical plug, referred to as a "torpedo plug", 176, generally includes a conical front end 178 with a nozzle 180 at its initial end. The conical portion 178 extends rearwardly to a short cylindrical portion 182 covered by an end plate 184. The plate 184 includes an inlet 186 and a hose switch 188 to connect a steam or hot water hose so that pressurized hot liquids can be introduced into the pleated tube. Other hose connections may have an end plate 184. The end plate 184 includes an inlet 186 and a hose connection 188 to connect a steam or hot water supply line so that pressurized hot liquids can be fed into the pleated pipe. The end plate 184 may have other hose connections, such as an air hose connection, to expand the air pressure pipe or to maintain air pressure in the expanded pipe when repaired in its expanded, rounded state.

After the trailing end of the pleated tube 10 has been heated, e.g., using the head heater 152 described above to make it flexible, the conical portion of the torpedo plug 176 is inserted into the trailing end of the tube 10 as shown in Figure 19 until the end closure 184 ends against the end 25 of the new tube. the end of the tube into a rounded shape so as to conform to the outer diameter of the cylindrical Tulp portion 182. An adjustable chain press 190 is used to press the expanded end of the new tube into the cylindrical portion 182 of the torpedo plug, sealing the tube 30 tightly to the plug.

. Details of the chain press 190 are shown in Figures 20 and 21. The chain press includes a press plate 192 having a curved tube mounting surface 193. A fork 194 rises from the convexly curved outer surface of the plate, between which the screw member 195 is pivoted. The screw member 195 receives a threaded rod 196 having a torque head 94283 35 197. A compression chain 198 is connected to the opposite end of the rod. The chain is preferably a transmission chain or a bicycle chain or the like. The chain is adapted to be in an adjustable connection to the attachment point 199 on the outer surface of the pressure plate 192 5.

After the end of the tube 10 is heated and flexible and the torpedo plug 176 is inserted into such an end, a press plate 192 is placed on the end of the rounded tube and the chain 198 is wrapped around the end of the cylindrical tube, tightened as tightly as possible by hand, and then secured at 199. is then used by rotating the threaded rod 196 in any direction to shorten the effective length of the compression chain 198 using a torque member located at the torque end of the rod 15 197. It is important that the compression be easy to tighten because the plastic tube tends to deform when heated and the compression must be tightened - and during the rounding process.

Once the torpedo plug is pressed into place at the rear end of the tube just inserted 20, the steam line is connected to the plug connection 188. Hot steam is forced along the length of the pleated tube, more specifically through small passages, thus allowing the entire length of the tube to heat up. By making the tube pressed by the end press at the front end of the pleated tube, the tube is always internally pressurized to 1.73 kp / cm 2. As the tube heats up and pressurizes, it expands and rounds to its cylindrical shape along its entire length except at its compressed end.

When the new pipe is expanded and rounded to its desired dimensions, usually against the inner wall of the existing side line, the plastic pipe is allowed to cool when it is under internal pressure, for example by supplying pressurized air, allowing the new pipe to remain permanently in its rounded shape. Once the new tube is established, the 36 94283 chain clamp is removed from its stern end and the torpedo plug is removed.

The next step is to remove the still pleated and pressed front end of the end press and the new tube from the remaining rounded portion of said tube. This is accomplished by cutting the compressed and pleated front end of the expanded and rounded new tube, as shown in connection with Figures 22 and 23.

Figures 22 and 23 show a cutting device for cutting off the pressed and folded front end of the expanded and rounded expanded and rounded tube 10, as shown in Figures 22 and 23.

In Figures 22 and 23, a cutting device is shown to cut off the wetted and compressed front end of the expanded and rounded tube 10 from an existing tube. The cutting device includes machine-operated cutting means 200. The cutting means includes a small very high speed electric or air motor 202 inside the cylinder motor housing 204, being substantially smaller in diameter than the inner diameter of the rounded plastic tube 10. The flexible air hose or power line 206 supplies power to the motor 202 from the inlet from the remote source to the existing connection pipe. A rotor 210 is mounted on the motor-driven shaft 208, to which a pair of cutting or shank tip-like blades 212, 213 are secured by pin joints 214 near the outer ends of the rotor.

The motor housing 204 is surrounded by an expandable rubber sleeve 216 which, when expanded, centers and secures the cutting unit in place within the rounded molded tube 30. The flexible air supply line 218 takes compressed air to inflate the slender.

'Although the shank blades shown in the figure are made of steel, they may also be made of chain or cable. They are designed to propagate outward under a mean force of 35 as the rotor 210 rotates, to shank and cut the plastic tube 10.

<> Ml lii i · IMU. i 94283 37 In use, the cutting unit 200 is inserted through a new plastic tube 10 after the tube has been installed and rounded. The pushing can take place with a flexible fiberglass rod and the rubber sleeve 216 5 being emptied of air. The cutter is inserted into the existing connecting pipe until it comes to the assembled and compressed front end. At this point, the sleeve 216 is expanded to secure and center the cutting portion inside the rounded plastic tube. When the sleeve is fully inflated, the motor 202 is powered to supply current through an air hose or electrical line 206. The motor rotates the rotor 210, actuating the shank blades 212, 213 until the blades cut across the compressed and pleated end of the plastic tube. The cut head falls into the main tube and can be removed therefrom using conventional methods.

After the front end of the tube is severed, the sleeve 216 is evacuated and the cutting unit is removed from the rounded plastic tube by simply pulling 20 from the air hose 218 and the electrical conduit 206 from the inlet end of the new tube. The new side pipe is installed in the existing side pipe and, after being connected to the part of the side pipe leading to the building 96 (Fig. 7), it is ready for use.

Fig. 33 shows an alternative method of pulling a pleated plastic tube 10 through the inlet 98a into an existing side tube 90a that meets the main tube line 94a at the intersection 92a. At some distance from the cutting point 92a, the main pipe 94a has an inspection opening 216 30 for access to the main pipe. The cable winch 218 is positioned. to the inspection opening 216. The front end of the traction cable 220 is fed into the existing connection pipe 90a at the inlet opening 98a and pushed down into the side pipe intersection 92a by a flexible fiberglass rod having a gripping device 35 at its front end to engage the front end of the traction cable.

94283 38

The front end of the push rod is also curved so that when it enters the intersection, it can be guided around a sharp angle to the main tube. At this point, the push rod continues to push the traction cable 220 through the main tube as shown in step 5a until the front end of the traction cable is attached to the winch cable at 219. The end of the traction cable 220, still at the inlet 98a to the side tube 90a, is connected to a pleated tube 10 the cable disconnection method described above. After the new tube is heated, for example in the heat box 18, to become flexible, it is drawn into the existing connecting tube 90a by a winch cable 220 using a winch 218 in the inspection opening 216. The pulling continues until the front end of the new tube 10 reaches the connection 92a. The pull-15 game 220 is detached from the front end of the new tube using any of the techniques described previously. The new tube is now ready to be expanded and rounded within the existing side tube 90a using either the previously described rounding method or another described '20 method.

Figures 25 to 29 show another method and apparatus for extending a newly installed plastic pipe into an existing connection pipe. This method is called the blow plug method. The inflatable plug 222 used in this method v5 is shown in Figures 25 and 26. It is used in place of end press 144 (Figures 12-13) or end press 250 (Figures 39-41) to close or shrink a hard-to-reach front end of a new plastic tube so that such tube can be pressurized. and expand. The plug is designed to withstand an atmospheric pressure of at least 1.73 kp / cm2 to expand to the size of the inner diameter of a new tube rounded from the outer diameter, but not to crack if the new tube does not shrink it. The plug can also be designed to withstand 35 temperatures above 93 ° C.

94283 39

The inflatable plug can be constructed of a single layer of flexible material if a suitable material is available that meets the above specifications. However, such a suitable material has not yet been found. Today, the plug therefore uses a two-layer structure. The stopper is made of an outer tissue or other fabric tube 224 folded, closed, and sewn to its front end 225. The outer tube 224 has an expanded diameter corresponding to the desired inner diameter of the new tube when rounded. The end of the fabric hose 226 remains open. An expandable rubber inner tube, or membrane 228, is placed inside the fabric tube. The total length of the plug can vary from about 30 centimeters to six meters, depending on the application. The ends of the outer fabric tube and the rubber inner tube are assembled into a tube body 230 which provides an air tube connection 232 to the air or steam supply tube 234 to supply pressurized fluid to the inner tube. The sterns of the outer and inner tubes are assembled 20 around the tube body 230 and tightly bonded by a bonding press 236 to prevent pressurized fluid from escaping the inner tube.

The expandable plug described above is typically used when installing and rounding new connecting pipes, so there is no need to use the main presses and end cutters described previously. The typical use of an expandable plug is as follows:

The required amount of pleated plastic pipe for one particular existing connecting pipe is heated 30 and rounded by comparison using, for example, the steam hose described above. The hose 234 used to pressurize the tube is fed through the length of the rounded plastic tube with an expandable plug attached thereto until the plug is positioned in the front end portion 35 of the rounded plastic tube.

94283 40 At this point, a pre-cut amount of rounded plastic tube is reheated and refolded with a plug that is not expanded and connected to an air tube folded for field use. Fig. 27 shows the inlet of the air tube and the deflated plug 222 connected to the rounded plastic tube 10. Fig. 28 shows the refolding of the tube 10 with the deflated plug 222 and the hose 234 inside the pleated tube.

10 At the workplace, the plastic pipe is heated and inserted into the connection pipe to be repaired when folded and flexible. Once fully inserted, the pleated plastic tube, with its stoppers, is heated while still empty of air by passing steam through the tube. When the entire length of said installed plastic tube is heated, the plug is inflated by air hose 234 to expand the plug and thus, while still hot, the flexible front end of the plastic tube 10 surrounding the plug is made to completely close the front end of the plastic tube. The plug is then inflated 20, the plastic tube at the top of the plug is pressurized with, for example, compressed air, rounded and expanded using air supplied by a hose 236 which leads to a torpedo plug 176 at the inlet 98 of the new tube.

2b After the new plastic tube is completely rounded and expanded to the desired diameter within the existing side line 90 and then allowed to cool, air is vented from the plug 222 and pulled out of its newly rounded tube 10 by its air hose 234. The newly installed plastic side tube is now ready for use.

Figs. 30 to 32 show other methods of using the expandable plug shown above.

A small variation of the method shown in Figures 27-29 is the use of an expandable plug as a slide plug during the rounding process of the put-35 ken. According to this variant, 94283 41 with reference to Fig. 30, the expandable plug 222 and its air hose are mounted on a pre-rounded plastic tube 10 and pleated as before with the tube, but said tube is placed about 15 cm from the front end 238 5 of the tube, allowing said front end is pleated as tightly as possible to facilitate insertion into an existing side tube. The pleated tube 10, which has a deaerated plug 222 inside, is installed pleated as before in an existing side tube. The stern end of the new tube is closed by a torpedo plug 176 as the air hose 234 extends through the closure in the torpedo plug.

After the expandable plug 222 has been emptied, the pleated tube is heated with steam from the inside to its entire length of 15 to make it flexible. The air hose 234, where it extends from the torpedo tube 176, is pulled tight and a clamp 240 is placed in the hose about 30 cm behind the stern of the torpedo plug. When the pleated new tube is hot, the expandable plug is inflated to full air. In addition, the pleated new tube between the expanded plug 222 and the torpedo plug 176 is pressurized with compressed air injected through the torpedo plug through the air line 236. Pressurizing the new tube forces the expanded plug 222 to slide toward the front end 238 of the new tube until it stops the torch 240. At this point, the front end, like the rest of the other newly installed pipe, has been made completely rounded. The expanded plug 222 is now evacuated and pulled out of the newly installed pipe.

Fig. 32 shows another method of using an expandable plug 222 to close, round, and expand a new tube within an existing side or other tube that is accessible from only one end.

According to this method, a new tube is inserted into the connecting tube pleated using one of the techniques described above and without the use of a front end clamp or expandable plug to close or contract its front or end end. The pleated tube is steam heated on the inside so that it is made flexible along its entire length. When hot, the external press 242 is applied to the pleated tube about 3 meters downward from the torpedo plug 176. The upper three-meter length of plastic tube between the press and the torpedo plug is then rounded by supplying steam through line 236 through the torpedo plug to the three-meter pleated tube of the upper-10 end. The rounded three-meter tube is then allowed to cool in its rounded state.

The torpedo plug 176 is now removed and the expandable plug 222 is inserted at least partially in the expandable state to facilitate insertion into the rounded portion of the new tube. The torpedo plug 176 is re-inserted into the rounded end of the new tube by an air hose 234 from an inflatable plug extending therethrough. Now the clamp 242 is removed from the new tube and the expandable plug 222 is evacuated. The new tube is again heated with steam from the inside along its entire length to make it flexible again. When the new tube is hot, air is partially blown into the expandable plug 222. The internal pressure inside the new tube, which may be steam or atmospheric pressure, increases, and the partially expanded plug 222 is manually rotated through the new tube, which at this point is partially pleated open and partially rounded. When the expandable plug 222 enters the bottom or front end of the new tube, it is completely inflated to close the head. The new tube is now liquid-pressurized, fully rounded and thus cooled to be permanently in its rounded state. Once the new tube is installed, the expanded plug 222 is emptied and pulled out of the fully rounded tube.

A method and device 94283 43 is provided for closing the space between a new, rounded pipe and an existing pipe, when such pipes are cross-connected to another opening. A typical pipe cross-connection would be at the bottom of a house sewer pipe where it connects to the main sewer.

5 The joint is simply a compressible rubber sleeve surrounding the cross-connected end of the pleated new tube. It is typically 6.4 to 3.2 mm thick, but can be any reasonably thick sleeve. Typically it is 30.5 to 61 cm long, but may be another desired length.

Once the front end of the pleated new tube has been installed and can be accessed, e.g. through the inspection opening, the sleeve can be passed through the pleated end of the new tube by sliding before said end is rounded. Then, during the rounding of the put-15 head, the sleeve also rounds. The new pipe is expanded during the expansion phase until the rubber sleeve is tightly compressed between the new pipe and the existing pipe to form a liquid-tight connection. Different methods are used to connect the distal and inaccessible lower ends of the sewer pipes 20. An adhesive-backed rubber sleeve is used and the head is refolded into the sleeve attached to it. The pleated, new tube is then fed into the existing tube using one of the methods described above.

The use of the expandable plug described above is a preferred method of rounding and expanding the sealable end. With such a plug, expansion and thus sealing is made more complete and reliable than with the other methods described.

As mentioned above, it is preferred that the thermoplastic tube 10 be made in a pleated form as shown in Fig. 8. After the thermoplastic tube has first cooled and cured into such a pleated shape, said tube retains in memory the shape to which it tends to return when it is reheated and is free. This memory of its pleated shape 94283 44 can be utilized to move a damaged part of such a pipe from an existing underground pipe.

To remove the damaged thermoplastic pipe from the 5 existing pipelines, the damaged pipe is heated by passing the right steam through it and, if possible, around it to the outside. When it is hot, the damaged removable tube section collapses to its original pleated shape. This assembly and re-folding can be accelerated by connecting a vacuum pump to the inside of the tube to reduce its internal pressure. Once it has collapsed and folded, the hot plastic pipe can be drawn from the existing pipeline with a cable winch with a traction cable attached to the accessible end of the collapsed pipe.

Heating the pleated thermoplastic tube to facilitate insertion, especially when it has to fit into the bends of an existing tube or conduit through a narrow, deep vertical hole, is important. Several heating methods for insertion have been described, including the use of a heat box or a long steam tube. Another method is to heat the interior of the existing pipeline into which the thermoplastic pipe is to be inserted. According to this method, a small part of the pipe with a steam connection is connected to the stern of the existing pipe to be repaired. A fabric closure at the rear end of the steam pipe section is wrapped around the pleated new pipe as it is fed through the steam pipe connection to the existing pipe to heat the new pipe 30 during its insertion. This method can also be used advantageously with other described heating methods.

The flattened, pleated shape of the rigid, point 20, thermoplastic tube shown in Figures 3 and 8 is also important because such a shape confers on the tube some properties that are impossible in other tubes that 94283 45 may collapse or partially collapse to reduce their overall cross-sectional dimensions when inserted. to an existing pipe. The first shown flattened and pleated shape, when heated and made flexible, can be stored effortlessly and tightly in long or short lengths on a reel. The coil, in turn, can be used for storage, reheating, and feeding the pipe into the line.

Second, the tube shape shown, when heated and flexible, can be introduced into the pipeline around a sharp bend from a small vertical inlet, such as an inspection port, and can be installed around sharp bends in an existing pipeline. For example, a rigid PVC pipe having a typical wall thickness / diameter ratio within the above limits, when flattened and pleated into the unique shape of Figures 3 or 8, has a minimum deflection / rounded outer diameter ratio of between one and two. . That is, a typical 10 cm diameter rigid PVC pipe, when flexible, flattened and pleated as shown in Figure 3 or 8, will survive an arc with a radius of 10 to 20 cm depending on the wall thickness without breaking the pipe walls. Such a minimum bending deflection is not achieved by using previously known shapes of other rigid thermo-25 plastic tubes when they are in their flexible state.

Thirdly, despite the above-described properties in heated and flexible form, the pleated tube shapes of Figures 3 and 8 can be easily reshaped into a round shape and made structurally rigid and strong enough to withstand external ground and hydraulic pressures. Thus, the installed thermoplastic tube of the present invention is a true replacement tube, not just the inner tube to the damaged existing tube.

46 94283

Having described the principles of the applicant's invention using several preferred embodiments and variations thereof, it should be apparent to those skilled in the art that the invention may be modified in various ways without departing from the said principles. I claim that the preferred embodiments of my invention and all modifications, variations, and equivalents fall within the true spirit and scope of the following claims.

il. Ulia t l i at i

Claims (26)

94283 47 A replacement pipe product for installation inside an existing pipeline (14), characterized in that it is a piece of substantially rigid thermoplastic pipe in a reduced form (10a) so that the pipe can be made flexible by heating, the pipe tending to maintain the reduced shape and expandable to the desired size, substantially tubular shape, wherein the maximum size of the tube 10 in the reduced form is smaller than its size in the tubular form. Replacement tube product according to Claim 1, characterized in that the thermoplastic tube is polyvinyl chloride. Interchangeable tube product according to Claim 1 or 2, characterized in that it is a section (10a) of thermoplastic resin material, the tube being substantially rigid at ambient temperature and flexible at a predetermined elevated temperature and expandable to the desired size, substantially tubular shape, a flattened and longitudinally pleated shape and first and second branches (83, 84) connected in a rounded spherical longitudinal pleat portion (82), the first and second branches (83, 84) of the pleated tube (10a) terminating in rounded spherical free ends (85, 87) defining fluid passages (86, 88, 89) through the pleated section of tube, and wherein one (83) of the arms is longer than the other (84) so that the spherical end 30 of the shorter arm (84) 87) is behind and overlapping the spherical end (85) of the longer leg (83), whereby the pleated tube (10a) ) the total thickness is as small as possible. An exchange tube product according to claim 3, characterized in that the tube has a memory of the lithium-35 and pleated shape. .. »« 83 A method of manufacturing a thermoplastic tube in a reduced form (10a), characterized in that the thermoplastic tube material is extruded in a hot and plastic state through a matrix (118) 5, whereby the plastic material is formed into a tubular shape (10) of the desired size, the obtained hot tubular plastic material is fed through a calibration device (126) having dimensions and shape such that the hot tubular plastic material acquires and maintains the desired reduced shape, and cooling the thermoplastic material in its reduced form (10a) to cure the thermoplastic material to this reduced shape. The method of claim 5, further comprising the step of providing a partial vacuum (125) to the hot plastic material in the calibrator. A method according to claim 5, characterized in that the tubular plastic material is formed into a flattened and longitudinally pleated mold (10a). A method according to claim 5, characterized in that the tube is heated in its reduced form (10a) to make it flexible and the flexible tube is wound in a reduced form on a storage roll (116). Method according to Claim 8, characterized in that the heating takes place by applying steam (115) to the pipe. A method according to claim 5, characterized in that the obtained hot tubular thermoplastic material is fed in plastic form before any substantial cooling through openings in the calibration plate set (128) of the calibration device (126), the openings being sized and shaped to flatten the tubular plastic. and decreases to a predetermined reduced size (10a) 94283 49 while providing a partial vacuum and a temperature higher than the memory-providing temperature for the thermoplastic material in the plastic material, then cooling the flattened and pleated tube as it is drawn through the calibration plates (128). out of them to reduce the shape of the tube, the flattened and pleated tube is reheated to make it longitudinally flexible, however, at a temperature lower than that which changes the memory properties of the thermo-10 plastic material. temperature, and placing the flexible tube in flattened and pleated form (10a) in a storage space where the tube is layered. Method according to one of Claims 5 to 10, characterized in that the exchange tube is made of polyvinyl chloride. An apparatus for making a rigid thermoplastic tube section in a reduced form, the tube having a memory of the reduced form, characterized in that it comprises an extruder (106) for extruding thermoplastic material in a hot plastic state into a tube section (10) having a desired size, substantially tubular cross section, and cooling means (126, 122) for shaping and holding the extruded thermoplastic material into the desired reduced shape (10a), all dimensions being smaller than the tubular shape (10). Device for manufacturing a pipe section according to claim 12, characterized in that it further comprises pressurizing means (125) for extruding. to maintain the shape of the material in the calibration means (126). Device for manufacturing a pipe section according to claim 13, characterized in that the pressure means (125) are vacuum means for acting on the outside of the pipe. 94283 50 A method of installing an exchange tube (10) of substantially rigid thermoplastic material in an existing pipeline at ambient temperature, the method comprising introducing the exchange tube into an inlet opening of the existing pipeline in a reduced form (10a) expandable to a tubular shape having substantially the desired outer diameter the inner diameter of the pipeline (14) is heated to a longitudinally flexible section of the exchange tube (10a) in a reduced form, the front end of the exchange tube (10a) is brought into the existing pipeline (14) in the heated flexible state, the exchange tube (10a) is placed in the existing pipeline (14), round the exchange tube (10) from its reduced shape to the tubular shape by applying heat and internal pressure thereto, and cool the exchange tube (10) to stabilize it in the tubular shape, characterized in that an exchange tube is used which the exchange pipe is made in a flattened and reduced form (10a) so as to retain a memory of such a reduced form in which the maximum size is smaller than the inner diameter of the existing pipe (14). A method according to claim 15, wherein the existing pipeline is a side line (90) connected to the main line (94), characterized in that the exchange pipe (10) is inserted into the side line (90) from its inlet point (98) to the main line (94). ) and the exchange pipe (10) is placed in the existing pipeline (94) with a cable holding device (152, 168) so that when the first end of the device (168) is pulled from the inlet (98) away from the main line (94) the other end of the device pulls the exchange pipe (10) facing the main line (94). Method according to claim 15, characterized in that the ability of the liquid 35 to flow from the opening of the front end of the exchange tube (10) before applying internal pressure 94283 51 to reshape the exchange tube (10) is limited to allow liquid pressure to flow into the exchange tube (10) and hot liquid through a section of the exchange tube (10) and then spraying the heated liquid from the end of the exchange tube (10) into it, the temperature and pressure of the liquid being sufficient to expand the exchange tube from its reduced shape (10a) to round. A method according to claim 17, characterized in that the flow of liquid from the front end of the exchange tube (10) is restricted by closing the front end with a flexible foldable and expandable plug (222) inside the flattened and folded exchange tube. A method according to claim 15, characterized in that the flattened and pleated tube is reheated to make it longitudinally flexible, but at a temperature lower than the temperature changing the memory properties of the thermoplastic material, and placed in a flattened 20 and pleated form (10a). where the pipe is layered. A method according to claim 15, characterized in that the exchange tube (10) is rounded with sufficient heat and internal pressure to form bulges (76) corresponding to the inner tube. the location of the joints (74) of the lever tubes, locating the bulges (76) and removing a portion of the exchange tube at the bulge (76) to provide an inlet for connecting the side tube. A method according to claim 15, characterized in that it comprises the step of rounding the front end of the exchange tube (10), attaching the expandable sealing sleeve around the rounded front end of the exchange tube (10), refolding the front end 35 before inserting the exchange tube (10), and 94283 52 after being placed, the exchange pipe (10) is heated, rounded and expanded, whereby the sealing sleeve is tightly pressed between the exchange pipe and the existing pipeline. An apparatus for installing an exchange tube (10) within an existing pipeline (14), the apparatus comprising storage means (20) for a portion of an exchange tube of substantially rigid thermoplastic material, the tube having a front end and a rear end in a reduced form 10 (10a). Tine exchange tube is stored in reduced form (10a), wherein the pipe is bent and folded together, and which includes a housing (18) stored for the pipe, the moon-heating means (24) of the housing inside of the heating to bring the 15 of the rigid pipe to a flexible state, means (26) of the flexible, pulling the front end of the flattened and pleated tube (10a) out of the housing (18), means for inserting the front end of the exchange tube (10) into the existing pipeline (14) in a heated and flexible state, and pressure means (30, 32, 38, 40 ) to expand the inserted replacement tube from its reduced round shape a space within an existing pipeline comprising restraining means (48) at the front end of the flattened pipe to allow heated fluid to pass through the flattened and pleated section of pipe to increase internal pressure within the section of pipe and means for directing heated fluid into the pipe from its rear end; that the thermoplastic exchange tube (10a) is made in a flattened and pleated reduced state and can be expanded to the desired roundness. state (10), thereby retaining a small amount of memory. Device according to claim 22, characterized in that the pressurizing device comprises a or 55 wooden and inelastic tubular cover (224) closed at the front end (225), a tubular flexible inflatable inner membrane (228) inside the cover (224), which is fluid under pressure to the expandable membrane, the coating may be rounded tubular shape, and a connection device (236) aft of the film 5 from the inner side of the film connecting the source of fluid pressure (234). Device according to claim 22, characterized in that the exchange tube (10a) in a reduced form is flattened and folded in its longitudinal direction and has a cross-section with one rounded spherical part on one side (82) and first and second branches (83). 84) connected to the rounded spherical portion (82), the first and second arms (83, 84) terminating in rounded free ends (85, 87) defining fluid passages (86, 88, 89) through the pleated pipe section, and the first the branch (83) is longer than the other (84), so that the spherical end (87) of the shorter branch (84) is behind and overlapping with the spherical end (85) of the longer branch (83), whereby the total thickness of the pleated tube (10a) can be minimize. Device according to one of Claims 22 to 24, characterized in that the exchange tube is made of polyvinyl chloride. Device according to claim 8, characterized in that it comprises an end-end heater (152) for heating the end-end of the exchange tube (10) to a flexible, machinable space in order to facilitate the insertion of the end stopper (32) restricting the flow of liquid. «Pp. 94283 54