WO1995029361A1

WO1995029361A1 - Process and device for renewing or repairing pipelines

Info

Publication number: WO1995029361A1
Application number: PCT/CH1995/000092
Authority: WO
Inventors: Hans Peter Von Burg; Rudolf Nuescheler; Eric M. Wille
Original assignee: Inc Bauchemie Ag
Priority date: 1994-04-26
Filing date: 1995-04-26
Publication date: 1995-11-02
Also published as: AU2212495A; EP0757771A1

Abstract

In order to repair or renew non man-sized pipelines, a pack, if required together with a transport head (1) and a transport film (8), is introduced into a pipeline (24) having a small diameter from about 10-30 cm. The UV-curable film (19) is pressed against the inner wall of the damaged pipeline (24) by an overpressure generated in the inflatable hose (9) and is cured in a short time by the UV-radiation source (18) that may if required be moved in the pack in the longitudinal direction. The length of the film of a pack may vary between about 20 cm and 10 m, according to the length of the used inflatable hose (9) and of the film (19) wound thereon. This process is thus suitable both for repairing local damages and for renewing whole pipeline sections of more than 100 m length.

Description

Method and device for the rehabilitation or repair of pipelines

The present invention relates to a method and a device for the renovation and renewal of non-accessible pipelines.

Escaping gases and liquids from old or damaged pipelines can cause ecological and economic damage. Renewal work by digging out the old pipelines and replacing them with new ones is often very difficult or even impossible, especially in the case of built-up land and the resulting damage and disabilities to the structures.

There are therefore procedures for renovation or. Proposed for the repair of damaged pipelines, in which the existing pipelines are given an inner lining.

General uss in the maintenance of pipelines between repairs (measures to restore the target state in the event of localized damage), renovation (measures to restore the target state of defective pipelines by changing them technically while preserving their substance) and renewal (measures to Production of new channels which take over the function of the old ones which have been taken out of operation; this can be carried out at the same location by replacement or elsewhere).

In principle, methods and devices are known in which an entire tube is lined with a tubular material, for example made of polyester needle felt, by means of an inner lining. Acrylic felts, glass fleeces and glass fabrics, together with synthetic resins, such as polyester, epoxy and vinyl ester resins, are laid out, this material then being cured on the inner surface of the tube by means of heat or UV light. In these so-called everting processes, a film tube curable with adhesive is usually pressed into the pipeline with the aid of a pressure medium and held in a dimensionally stable manner until the adhesive has hardened. However, the film tube can also be conventionally drawn into the tube and expanded therein. By definition, such methods and devices are generally used for the rehabilitation of pipelines. A disadvantage of these methods is the fact that it is economically pointless to renovate an entire pipe, which can often be longer than 100 m, if it is damaged in only a small area.

Nowadays, in ection processes are mostly used to remedy local leaks, such as can be found in the socket areas and transverse cracks. Sealing takes place with so-called packers - special devices with two inflatable sealing sleeves and a rigid or flexible middle part. These are placed over the damaged area and then a synthetic resin is pressed into the non-leaky area. Synthetic resins based on acrylic resins or polyurethanes are usually used as injection means. By definition, such methods and devices are generally used for the repair of pipelines.

In both methods, a more or less large cross-sectional narrowing of the pipelines must generally be accepted.

For economic reasons, an attempt will be made to repair a pipeline if possible and only if this proves to be impossible to renovate or even replace it perform. It also shows that all known methods and devices are suitable either for repair or for renovation. Methods and devices are very different in each case and usually require complex device technology directly on site. This has disadvantages because it is necessary to decide in each case for completely different processes, which usually cannot be carried out by the same provider, so that in many cases a tailor-made solution in which longer and shorter pipe sections are carried out using the same process and repair the same device. could renovate, would be of great practical advantage.

It is therefore an object of the invention to provide a simple, universally applicable method and a device for repairing or. To provide renovation of non-accessible pipelines.

The task is solved by a method and a device for repair or Rehabilitation of pipelines with the characterizing features in the independent claims in cooperation with the generic term of these claims and the corresponding dependent claims.

In connection with the device according to the invention, the method according to the invention has the advantage that both short (for example 20 cm for sleeves) and long pipe sections of up to more than 100 m in length can be achieved quickly and inexpensively with a single simple method can be repaired without significantly reducing the tube cross-section.

Thanks to the thin walls of the film used, the process is also suitable for lining pipelines with small cross sections of 10-30 cm, with pipe sections from about 20 cm to about 10, preferably up to 6 m, can be lined in one piece. When lining longer pipe sections of up to more than 100 m, individual film sections can be strung together in an overlapping manner. For the lining of pipelines with a cross section of approx. 10-30 cm, 1 to 4 different sizes of train, transport and inlet heads are required.

Thanks to the device which is flexible in one embodiment, the method can be used both for straight and curved pipelines, in practice bends remaining easily processable up to approximately 45 °.

As a film for lining the pipelines, there are those which are waterproof and curable by UV light. Laminates have proven to be suitable which contain a layer of fibrous reinforcing material, preferably made of fiberglass (= E-fibers), and a layer of carrier material, both layers being coated with a curable polymer composition in such a way that the laminate becomes water-impermeable during curing. A glass fiber fabric is preferably used as the carrier material and a polyester resin which contains a UV catalyst is used as the curable resin. Isophthalic acid ester resin is particularly suitable as the resin and benzoylbutyl ether as the UV catalyst. The quantity ratio of fiberglass resp. Glass fiber fabric to polyester resin ranges from 4: 1 to 1: 4. The outside of the laminate is preferably protected and supported by 2 thin protective foils, preferably made of PVC, nylon or polyester. The laminate structure of the film has the reinforcing properties of fiberglass and, at the same time, the impermeability of impregnated glass fiber fabric.

For better adhesion of the film to the inner wall of the pipe, an adhesive primer can be applied to the protective film on the pipe wall side. As for this purpose orthophthalic esters esterified with ethyl glycol, propyl glycol, butyl glycol or glycerol have proven suitable.

For better sealing of the pores on the inside of the film, e.g. Unsaturated isophthalic acid esters esterified with ethanol or propylene glycol can be used as a top coating.

The film is rolled up into rolls of any size and covered with an opaque protective cover. In this way, the film in the form of a roll can be transported, stored and used on site by removing the opaque protective cover, cutting the film to the desired size and rewinding the remaining film roll with the protective cover.

The film cut to the desired size is then wound onto the suitable pack, consisting of a pulling head, inlet head and hose with a UV lamp movably mounted therein. If the feed distance is long, e.g. more than 5, or is bent, a transport head with an attached, reusable, opaque transport film made of e.g. PVC, PE or PP is put over the pack to protect the film while it is being pulled into the pipeline and the pack together with the transport head and Transport foil pulled into the pipeline by means of pull cables attached to the heads and positioned over the damaged area. It is important to ensure that the transport head or. Traction head and inlet head about 2-8 cm smaller cross sections than the pipes.

An inflatable, highly elastic, high-tensile and transparent material is suitable as the hose. Soft UV-resistant silicone, PA, PVA, PU, PE or PVC hoses with rubber-like elasticity and extreme expansion options have proven particularly suitable and very high strength values in tear and abrasion resistance, as they are offered on the market. The hose material can be cut to lengths from approx. 20 cm to 20 m and more and attached airtight at one end to the pulling head and the inlet head.

By staggering several longer packs of e.g. 6 m in length and overlapping from their ends, pipes of up to 200 m can be renovated relatively quickly.

Depending on the length of the pack, between 1 and 8 UV radiation sources arranged one behind the other and connected to one another by flexible joints can be used, preferably in the form of a rod, in the same pack. UV radiation sources available on the market are preferably used in the high-power range with optimum radiation yield in the UVA wavelength range, which are particularly suitable for curing polyester resins and yet have only a low level of heat radiation. This gives curing times of the polyester resin of less than 1 minute, preferably less than 30 seconds, in the region of the UV lamps.

The transport head and the transport film, which may be present, are removed from the pack with the aid of the traction ropes attached to the traction head and inlet head with a further traction rope fastened to the transport head and an overpressure of 0.5-1.5 bar by means of a compressor generated in the hose. As a result, the film is pressed against the inner wall of the pipeline. The curing process of the polyester resin can now be started by the UV radiation source. At the same time, the next pack can be prepared when processing longer pipe sections and, if necessary, wrapped with the previously removed transport head and the transport film. If the tube is considerably longer than that used in UV radiation source, the entire length of the film _in, a few minutes can be cured by continuous or discontinuous displacement of the UV radiation source within the tube. Due to the short curing time and the materials used, no special cooling unit is required inside the hose despite the high output of the UV lamp.

After curing, the excess pressure is released from the tube and the tube is preferably evacuated, whereupon it detaches from the film. So that the hose can be detached from the film better, a wax-containing release agent can be added to the inside if necessary. The pack can now be removed from the pipeline using the pulling rope on the inlet or pulling head, for practical reasons the pack is preferably pulled out on the inlet head because of the cable required for the UV lamp.

If desired, e.g. a video camera can be installed. This eliminates the need for a measurement to position the film and the user can follow the entire curing process on the monitor.

Due to the measures described, non-accessible pipelines with a cross section of preferably 10-30 cm through a thin layer of 1-4 mm, preferably less than 2 mm, of a film according to the invention can be rehabilitated or. be repaired.

Another advantage of the invention is that the device and the method are equally suitable for the repair and refurbishment of short and longer pipe sections, because the distance between the traction head and the inlet head is variable. This allows the length select the curable film as required. In addition, according to the invention, several polyester film sections can be arranged one behind the other.

Since, according to the invention, the film is cured at low temperatures of approximately 40 ° -50 ° C. and high contact pressures, a firm bond is created between the inside of the pipeline and the film. Since the film does not shrink during the slight subsequent cooling, the bond remains, so that the film does not fall behind. In other words, the inflow of water between the film and the inside of the pipeline is prevented. The strong bond also allows the hardened film to be used for pipe connections or inlets e.g. is cut to the desired length with a cutter, without the end of the film with the tube being additionally covered with a cover ring, band or sleeve, etc. connected and sealed.

The invention is explained in more detail below with reference to the drawings.

1 shows a partial cross section through an embodiment of a device according to the invention while it is being drawn into a pipeline.

2 shows a further cross section through a device according to the invention during the curing process.

3 shows a cross section of a further embodiment of the invention before the start of curing.

4 shows a cross section of a further embodiment of the invention during the curing. 5 shows a cross section of an arcuate embodiment of the invention during curing.

FIG. 6 shows a cross section of an arcuate embodiment of the invention during curing.

1 shows a device according to the invention, which has a transport head (1) with a pull bracket (2), to which a pull line can be attached, and with a transport head opening (25) through which the pull line of the pull head (5) is guided , and with a transport film (8) slipped over the pack, which, for example is fixed to the transport head (1) by means of a clamping ring (4). The transport head (1) which is not rigidly connected to the traction head (5) can be removed from the pack on the traction line attached to the transport head as soon as it is positioned at the damaged point. The pack itself consists of a pulling head (5) with an eyelet (3), on which a not shown e.g. segmented towing line is attached. The towing line can be segmented so that the transport head (1), through the opening (25) of which the towing line is guided, can be easily disguised from the towing line at the interface of any segment.

The traction head (5) has an eyelet (3) to which the traction line of the traction head (5) is attached. Slide rollers (6) make it easier to pull in the pack if no transport head (1) and no transport film (8) are used. At the other end of the pack is the inlet head (10), which has an inlet or. Has outlet connector (14) for compressed air, an opening with a sliding seal (20) for the pull and power cable (12) of the UV lamp (18) and a pull ring (13) for a pull cable, not shown.

A UV radiation source (18) with a starter (15) arranged between 2 acrylic glass rings (22) and a protective tube (21) made of quartz glass is loose with the inlet head (10) Train and power cables (12) connected. The acrylic glass rings (22) each have at least two resilient spacers consisting of a tension spring (17) and bolts (16) with rollers (26) so that the UV radiation source (18) is at a uniform distance from the polyester film ( 19) can be moved in the air hose (9).

There are also rods or wires (23) fixed between screw head (5) and inlet head (10) by screw pins (27, Fig. 2), which prevent the longitudinal expansion of the pack when pressure in the air hose (9) increases.

The air hose (9) is connected to the traction head (5) and the inlet head (10) in an airtight manner with the aid of clamping rings (7, 11) and the polyester film (19) is wound overlapping around the air hose (9), the length of the fo lie (19) must be a few centimeters shorter than the distance between the two facing ends of the traction head (5) and the inlet head (10) in order to ensure that it bears perfectly against the inner wall of the pipeline (24) .

2 shows an embodiment according to the invention during the curing phase. The air hose (9), which is fixed to the traction head (5) and inlet head (10) by means of clamping rings (28), presses the polyester film (19) against the inner wall of the pipeline (24) by means of excess pressure. The UV radiation source (18) is then pulled continuously or discontinuously from the pulling head (5) by means of the pulling and power cable (12) against the inlet head (10), the spacers consisting of tension springs (17) and bolts being folded out on the tube cross section (16) and rollers (26) which keep the UV radiation source (18) at a uniform distance from the polyester film (19).

The polyester film (19) wound on the outer wall of the air hose (9) is so long against the Inner wall of the pipeline (24) is pressed until it has hardened due to the UV radiation source (18). This process takes a few seconds to a maximum of 2 minutes in the direct vicinity of the UV radiation source (18).

The period of time within which the polyester film (19) can be cured in a tube section depends on the length of the radiation source for a given power of the UV radiation source (18). So you can at a radiation source length of 10 cm about 10-30 cm film length per minute, preferably about 20 cm per minute, respectively. if the radiation source length doubles, harden the film length 20-60 cm per minute, preferably 40 cm per minute.

After the hardening phase, the excess pressure is released from the air hose (9), the hose (9) detaching itself from the hardened polyester film (19), which now lies snugly against the inner wall of the pipe (24). The pack can now be pulled out of the repaired pipeline (24) on one of the pull lines.

A further embodiment according to the invention is shown in FIG. 3 during positioning in a pipeline (24). The pull cables (32), (51) and (40) serve this purpose. A traction cable (32) is fixed to the traction head (5) by means of a traction ring (33). The inlet head has a pull rope (40). During this process, the lamp unit (31) is fixed to the feed head (5) by means of the bolt (35) and the spacers (37) rest on the lamp unit (31) in order to facilitate positioning of the device in the pipeline (24). The transport film (8) drawn only on one side serves the same purpose. The traction head (5) also contains an exhaust air valve (34) which is combined with a bolt (35) for fixing the lamp unit (31) in a pipeline (24) during the drawing in and positioning of the device according to the invention. 4 shows the embodiment according to the invention from FIG. 3 during the curing phase. A release agent (36) is located between the tube (24) and the outside of the film (19). The lamp unit (31) contains a pneumatic cylinder (41) and pneumatically controlled spacers (37) which hold the UV lamp (18) on all sides at approximately the same distance from the curable film (19). Furthermore, the lamp unit (31) contains the ignitor. the starter (15) for the UV lamp (18) and a casing (38) for the ignition device (15). An air hose (39) is used to control the pneumatics for the spacers (37). The lamp unit (31) is pulled through the air hose (9) in the direction of the arrow at a predetermined speed by means of the power pull cable (12) in order to harden the film (19).

5 shows a further embodiment according to the invention during the curing phase, which is particularly suitable for renovation or. Repair of bent pipes (24) is suitable. For this purpose, the lamp unit (68) has a pull cable (61) fixed to a pull ring (62) on the rounded lamp head at the front (63), spacer rings (64) e.g. made of Teflon to keep the lamp unit (68) at a distance from the film (19) and a rounded lamp head at the back (65). The igniter with casing housing (67) is movably connected to the lamp head at the rear (65) by means of a universal joint (66) in order to be able to better circle around pipes (24).

6 shows the embodiment of FIG. 5 during the curing phase in a pipe bend. Due to the rounded lamp heads (63, 65) and the separate igniter with shuttering housing (67) flexibly connected to it by means of a universal joint (66), renovation or Repair work in pipe bends with angles up to 45 ° and more can be carried out easily with this type of construction. If several damaged areas located some distance from one another need to be repaired, this can be done by applying a plurality of packs each positioned at the corresponding damaged area. This is particularly the case when renovating pipe sockets. In the case of damage points located close to each other or when longer pipe sections need to be renovated, a longer pack of several meters in length or even several longer packs just overlapping one another in the edge area can be applied. The maximum possible length of a pack depends on the cross section of the pipeline (24), the accessibility of the pipeline (24) and any changes in direction required when pulling the pack into the pipeline (24) and can be up to approximately 20 lengths or more.

Claims

PATENT CLAIMS

1. A method for the repair or refurbishment of non-accessible pipelines of preferably 10-30 cm cross-section, characterized in that a wrapped around a pack by UV light curable film (19) is introduced into a pipe (24) and over the Damaged position, using a pressure medium, preferably air, presses the film (19) against the inner wall of the pipeline (24), cures the film (19) with a UV radiation source (18), releases the excess pressure and releases the pack from the Pipeline (24) removed.

2. The method according to claim 1, characterized in that, before the pack is inserted, a transport head (1) with the transport film (8) attached is placed over the pack and both are removed again before the pressure is applied.

3. The method according to any one of claims 1 or 2, characterized in that the pack with pulling lines attached to the pulling head (5) and on the inlet head (10) is inserted into the tube, positioned above the damaged point and removed again.

4. The method according to any one of claims 1-3, characterized in that the UV radiation source (18) continuously or discontinuously within the pressurized air hose (9) preferably on rollers (26) from the traction head (5 ) is moved towards the inlet head (10).

5. The method according to claim 4, characterized gekennzeich¬ net that the UV radiation source (18) depending on the radiation source length at a speed of about 10-30 cm per minute, preferably about 20 cm per minute, with a radiation source length of 10 cm resp. 20-60 cm each Minute, preferably 40 cm per minute, is moved with doubled radiation source length.

6. The method according to any one of claims 1-5, characterized in that for more than about 10 m, preferably over 6 m long pipes in need of repair (24) several packs staggered in time and place and slightly overlapping in the pipe (24) introduces, positions and hardens.

7. Device for the repair or refurbishment of non-accessible pipelines (24) of preferably 10-30 cm cross section, characterized in that it contains a pack consisting of a traction head (5), an inlet head (10), which has an inlet connector (14) for a pressure medium and an opening (20) for a pull and power cable (12) of a UV radiation source (18), a UV-transparent air tube (9), one inside the air tube (9) in the longitudinal direction preferably movable UV radiation source (18), which is preferably delimited against the air hose (9) between two glass rings (22) and a protective tube (21), and which consists of a film (19) wound on the air hose (9).

8. The device according to claim 7, characterized gekenn¬ characterized in that the device has a transport head (1) with an opaque transport film (8).

9. Device according to one of claims 7 or 8, characterized in that the two glass rings (22) of the UV radiation source (18) spacers for better mobility of the UV radiation source (18) in the longitudinal direction of the air tube (9) and more uniform curing of Has film (19).

10. Device according to one of the claims 7-9, characterized in that the film ■ '19) is a laminate, which contains between two outer layers of a protective film a layer of fibrous reinforcing material preferably made of fiberglass and a layer of carrier material preferably made of a glass fiber fabric, these two inner layers being impregnated with a UV-curable polyester resin which contains a UV catalyst .

11. Device according to one of claims 7-10, characterized in that an isophthalic acid ester resin is used as the polyester resin and benzoylbutyl ether is used as the UV catalyst.

12. Device according to one of the claims 7-11, characterized in that the film (19) on the tube wall side contains an adhesive primer, preferably an orthophthalic ester esterified with ethyl glycol, propyl glycol, butyl glycol or glycerol.

13. Device according to one of the claims 7-12, characterized in that the film (19) on the inside contains a top coating of unsaturated isophthalic acid ester preferably esterified with ethanol or propylene glycol.