DE2350976A1 - METHOD AND DEVICE FOR LINING PIPES - Google Patents

Description

TAKATA KOJYO CO., LTD., No. 10, Mori Building 28 Sakuragawa-sho ,, Nishikubo, Shiba, Minato-ku, Tokyo , Japan

Method and device for lining pipes

The invention is concerned with the repair of pipes, pipes, etc. and is concerned in particular with a method for the repair of large pipes (= pipes with a large diameter), which are difficult to access and, for example, under the floor as sewer pipes or supply pipes for water, Gas and the like can be misplaced. Long large pipes are used to a large extent for conveying liquid or gaseous media, for example as sewer pipes, water pipes, gas main _{pipes and other functional pipes o} Such pipes and pipes are usually only accessible in their full length with great difficulty, be it that they are laid under the floor or in remote areas. Furthermore, these pipes often require rapid repair because they often break or are otherwise damaged. This damage is usually a consequence of such events as sudden or considerable changes in the pressure difference between the inside and the outside of the pipe ₉ of underground works

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in the environment or from earth movements for a variety of reasons, for example also due to corrosion or erosion. To that allowed by the installed below ground pipes service in the intended way up quite hold ^ have serious leaks are immediately detected and repaired; Such a repair usually requires the replacement of a considerable piece of the large-diameter pipe, because the repair of a pipe section merely by welding or patching is usually less than satisfactory and, moreover, very difficult to carry out. However, especially in the case of underground pipes, the replacement of the pipe is rather difficult, expensive and very time-consuming and thus to a considerable extent uneconomical, because the pipe, with the exception of the weak points and the fractures, is still structurally undamaged and therefore has a long service life . It is not only necessary to dig a trench along the entire length of the pipe section to be replaced in order to be able to replace it. The transport of the large pipe to and from the repair site is difficult, expensive and time-consuming, because working with such pipes almost without exception requires the use of heavy-duty cranes and the like. The usual maintenance and upkeep of underground pipes and main lines is therefore very time-consuming5 and unsatisfactory in many respects.

The invention is therefore based on the object of an improved method for repairing damaged or defective ones To propose pipes, lines and the like «In particular, with the method and the associated device the repair of leaks in pipes, lines and the like carrying the medium with a large diameter are made possible. The invention is intended to address leaks in underground pipes or pipes that are otherwise difficult to access let repair. Of course, the

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Finding easy to use, reliable within reach Result, can be carried out relatively quickly, can be adapted to a wide range of applications and without special skills be feasible.

To achieve the stated object, the invention provides Method of repairing a leaking pipe in front of, inside and along a leaking pipe Pipe section to introduce a pipe made of a synthetic, organic polymer resin compound, under pressure to introduce stagnant gas into the pipe while it is in a soft state, up to the pipe to expand tight contact with the inner surface of the damaged pipe and then bring about the hardening of the liner pipe while it is in its fully expanded position Condition is. The resin compound may be thermoplastic, for example a thermoplastic polyvinyl chloride or polyolefin or the like. be, or can also be an untreated, soft, heat-setting resin that activates the hardening when exposed to heat, or at all a setting agent and a heat-setting inhibitor. Examples of suitable thermosetting agents Compounds are described in Belgian patent 772,973. In this case a thermoplastic resin liner pipe is used which, after being heated and expanded, advantageously can cool down before the pressure inside it is released whereas if a resin thermosetting tube is used, the pressure and heat will be maintained until the pipe has set. The outside of the pipe or the inside surface of the one to be repaired Rohres can be provided with an adhesive, preferably with a temperature-sensitive adhesive, to a Ensure a suitable connection between the outer and inner tubes on the opposing surfaces. The lining pipe is advantageously made with natural

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or reinforced synthetic fibers, for example with polyester, polyamide, glass fibers or the like. It turns out particularly useful when the fibers extend in the peripheral and in the longitudinal direction, the peripheral Fibers have a high unrecoverable elongation and the longitudinal fibers only have a low elongation. A fabric is expediently embedded in the lining pipe for reinforcement, in which the chain is in Extends longitudinally and has low elongation, whereas the filler extends in the peripheral direction and has high elongation, for example unstretched or underdrawn polyester, yarn or polyamide yarn.

The improved method is particularly advantageous when repairing burst or cracked underground pipes, such as utility lines. If not present, man or revision holes are indicated opposite ends of the broken pipe sections are dug after the pipe has appropriately drained and the section was separated from the adjacent sections so as to gain access to the interior of the damaged section. The collapsed slide-in tube is inserted into the cleaned tube and clamped to the pipe end flanges by end plates, whereupon hot pressure medium, for example air, is then circulated through the pipe until it has expanded and set if it is made of a thermosetting resin · The face plates become then removed and the repaired pipe section is then reconnected to the adjacent pipe sections. In sewer pipes, manholes are usually located at opposite ends of one behind the other Pipe sections so that digging, cutting and reconnecting is not necessary is. In addition, the lining method explained can also be applied to undamaged pipes before laying will. The procedure is simple, reliable and

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fast and requires little specialized work.

The above and other features of the invention will become apparent from the following description, wherein reference is made to the accompanying drawings o Show each one;

Figο 1 shows a cross section through a portion of the Lining pipe equipped with the features of the invention;

Fiq _o 2 a longitudinal section through a pipe laid under the floor and damaged, with the preparatory measures for its repair; and

Figo 3 is a .the Fig _o 2 similar _view? the apparatus for carrying out the method being evident o

According to the shown in the drawings preferred INVENTIVE of the invention for repairing an under-floor, laid pipeline piece designated the letter A in general the liner pipe ₉ while the letter B, the underlying soil 12, i-iobei be = damaged pipe referred to _s the ground 12 can of course be paved or unpaved ₉ depending on the respective circumstances. On the pipe B, in its unrepaired state, a broken part or a leakage opening 4 with inwardly pointing, roughened edges 4% is recognized, whereby the debris 5 from the opening 4 is has accumulated on the bottom of tube B under opening 4 «

The Ausicleidungsrohr A has a body or a matrix 3 made of a thermoplastic resin or a soft ₉ thermosetting resin compound of the above-mentioned property with a latent curing agent or crosslinker. As an example of a suitable resin compound in a latent thermosetting state, the following may be mentioned:

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Part of the weight file

Polyvinyl Chloride Resin 100

Acrylic ester thermosetting
Plasticizer

(Tetraethylene glycol dimethacrylate) 40

Diiso-octyl phthalate · 20 stabilizer (Cd.Ba stearate) 3

Thermosetting Trigger
(Di-t-butyl perbenzoate) 2

The resin is extremely flexible in its normal, untreated state at room temperature and has a hardness of about 85 (Shore D) at? 0 C. The thickness of the pipe A is preferably between 2 mm and 100 mm.

The Fatrix 3 contains embedded and connected to it a cylindrical reinforcing fabric with longitudinally extending fibers 1 and extending in peripheral ^ Direction of extending fibers 2, the compositions of which have already been explained above »The fibers or G.'rne and 2 are advantageously interwoven to form one Warp or a weft or a filling. The grease 1 has low elongation and is, for example, stretch-oriented Polyester or polyamide or glass fibers or the like, while the filling or the weft 2 has a high Has extensibility, for example unstretched polyester or Polyamide fibers · For example, the warp 1 can have an elongation of 10% and the weft or fillet 2 have an elongation of 100%, with a maximum elongation or break occurring at at least 600%, and there is an unrecoverable elongation of at least 25%.

In the repair damaged pipe sections B with the connecting flanges 6 at the opposite ends the pipe system in the event of a pressurized gas

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line or water pipe emptied of water or gas, the access to the end faces of the pipe section B is possible through existing manholes or can be obtained by ^{digging manholes or pits 7 and 7 1} on opposite end faces of the pipe section B and short connector pieces 6 · That connect pipe section B to opposite pipe sections, are removed. The holes 7 can be dug manually or by machine in the usual way. If access to the opposite end faces of the pipe section B is possible, the debris 5 is removed and the inner surface of the pipe section B is cleaned.

The device to insert the pipe A into the cleaned, damaged pipe B comprises a pair of apertured end plates 9 and 9 *, the diameter of which corresponds approximately to the diameter of the pipe end flanges 6, with suitable means being provided for to releasably clamp the end plates 9 and 9 'hermetically to the respective flange 6, for example by the end plates and flanges are provided with correspondingly spaced openings for the insertion of bolts which can then be tightened firmly. A portable air heater 10 of conventional design has an outlet which is connected to the inlet opening of the face plate 9 via a flexible hose, and has an inlet connected to the outlet of a motor-driven air blower 10, the inlet of which in turn is connected to the opening in the other end plate 9 ″ via a flexible hose. Usual facilities are provided for regulating the temperature of the circulating air that is heated by the heating unit 10, by controlling the unit 10 in a known manner. Facilities are also provided for additional To allow air to enter the circuit to reduce the pressure

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in the system to increase in the event that thermal expansion should not be sufficient to expand the tube A; the pressure can of course be done in other ways be regulated.

When inserting the pipe A, the outer diameter of which is considerably smaller than the inside diameter of the pipe B, into the interior of the pipe B, a section 8 of the pipe A is inserted over the entire length of the pipe B, while the opposite ends are widened after are flanged on the outside, resulting in end flanges which are squeezed between the respective end plates 9 and 9 and the associated pipe flange 6 when the end plates are clamped to the flanges 6. The heater 10 and the fan 11 are then switched on so that the air is warmed up and circulated through the pipe section 8, the circulating air being expanded and furthermore being pressurized by pumping in additional air, the heated circulating air Air at increased pressure expands the pipe section 8 and does not stretch the peripheral fibers 3 recoverably, so that the expanded pipe section 8 'hugs and rests firmly against the inside of the pipe B, the fracture point 4 as well as the entire inner surface of the pipe being lined. The hot circulating air is kept circulating until the resin of the pipe has set; For example, in the case of the special resin given above, the air is kept in circulation at room temperature of about 40 ^° C. to about 200 ^° C. for a period of 10 to 500 minutes, the fibers 2 being oriented by stretching and maintaining their stretched condition by virtue of their elongation »

After the resin has set or has crosslinked,

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the heater 10 and the fan 11 switched off and the Pressure was released from the system, the expanded pipe cooled and the end plates removed from the flanges 6 and removed through the holes 7. The pipe section B is then again with the help of the connecting pieces 6 · connected to the adjacent pipe sections and · finally, the holes 7 are re-established as desired filled up.

Note that in the above-mentioned operation, the expanded tube 8 'is usually attached to the inner surface of the Pipe section B is glued, although this is not necessary, especially if the hardness of the expanded Pipe 8 'allows at least one self-supporting of the pipe in the absence of internal pressure, be it that the resin is thermoplastic or thermosetting. However, in many cases it is desirable that the liner pipe and that the pipe to be repaired are connected to one another; therefore, if there is a connection in the case of the above Workflow cannot normally be achieved, an adhesive layer, which is advantageously heat sensitive or is heat-activated, on the outside of the lining pipe 8 or the inner surface of the pipe section B applied so that they are firmly connected to each other on the opposite surfaces.

A number of changes to the described embodiment of the invention are familiar to the person skilled in the art without this thereby deviating from the inventive concept. Overall, a broken repair method was found or otherwise damaged or weakened pipes of large diameter, for example from underground water or sewer pipes - described, in which the opposite end faces of the pipe to obtain a Access must be opened, the debris removed from the inside of the pipe and the inner surface smoothed. A

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Coating tube made of synthetic and organic resin Reinforced with peripherally stretchable fibers - the resin being either thermoplastic or thermosetting can be and is in an untreated condition - is in the pipe to be repaired a— set and clamped on the front sides with front plates and in close contact with the one to be repaired Pipe expanded by hot circulating pressurized air. One or both of the points to be pointed towards each other Surfaces of the pipe to be repaired and the lining pipe can be provided with a heat-sensitive adhesive be; When the resin of the lining pipe sets in the heat, the hot air is conducted through the pipe as long as until the resin has set. After that, the repaired pipe is re-attached to its end flanges connected to the opposite, adjacent pipe parts.

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Claims (10)

A η s ρ r ü c h e Method for lining a pipe, characterized in that a synthetic, organic polymer resin pipe (8) is inserted into the pipe (B), the outside diameter of which is smaller than the inside diameter of the pipe (B); that the tube _p, while it is in a soft, flexible state, is expanded into close proximity to the inner surface of the tube (B) with the aid of a pressure medium in the tube (8); and that the medium pressure is released and the tube Bb is cooled while it is in contact with the tube. 2. The method according to claim I _9, characterized in that.die tube has a resin compound which sets in the heat; and that the pressure medium is heated and circulated through the tube (8) until the resin has set substantially 3. The method according to claim 1 or 2, characterized in that that in the tube reinforcing fibers (2) are embedded, which extend peripherally. 4. The method according to claim 3, characterized in that the fibers have high elongation and when expanding the tube (8) cannot be stretched in a recoverable manner. 5. The method according to claim 3 or 4, characterized in that the fibers form the weft or »the filling of a tissue embedded in the tube _β 409817/0359 6. The method according to any one of the preceding claims, characterized in that end plates (9.9 ·) before the end face of the pipe B are brought; that the edges of the tube (8) between the end plates and corresponding End flanges (6) of the tube (B) are fixed: and that hot gas through the tube openings in the face plates. 7. The method according to any one of the preceding claims, characterized in that at least one of the Adhesive to opposite surfaces of the tube (B) or the tube (8) prior to the expansion of the tube is applied. 8. The method according to any one of the preceding claims, characterized in that the resin is thermoplastic is. 9. The method according to any one of the preceding claims, characterized in that the tube (B) has a first Has underfloor section, which is connected to adjacent second pipe sections at opposite end faces is; that holes are dug on the opposite end faces of the first pipe section, separating the first pipe section from the second sections to gain access to the first section; and that the tube (8) is introduced into the first tube section (B) prior to the expansion of the tube. 10. Device for carrying out the method according to one of the preceding claims, characterized in that that a heater (10) and a fan (11) are connected to two end plates (9, 9) via flexible hoses; and that the end plates can be tightly fastened to the end flanges of a pipe section. 40981 7/0359