RU2439420C2 - Device for air inverting and steam curing of tube insert cured at worksite - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: gland is controlled with many pins which are moved mainly perpendicular to the inverted insert so that it can be engaged with movable insert when it passes through the gland. After the gland of the pre-specified shape is adjusted, pressure on movable insert does not increase. When the insert reaches the rear end, it enters the template and tube for making an opening, which is equipped with outlet tube gland and outlet tube, and pierced with rigid tools for opening making. Then, steam is supplied to the insert to cure resin and discharged through outlet hose connected to the opening making tool. After curing the steam is replaced with insert cooling air and ends are cut in order to restore the service by means of the existing pipeline.

EFFECT: device has low-friction seal located between movable insert and fixed inverting gland.

12 cl, 10 dwg

Description

FIELD OF THE INVENTION

This invention relates to devices for mounting an on-site curable liner into an existing pipeline by air inverting (turning inside out) a resin-impregnated liner using a device having a low friction seal. The resin can be cured by continuously pumped steam without pressure loss. These devices are applicable for the internal coating of pipelines of small and medium diameter.

It is known that pipelines or utilities, especially underground pipes, such as sewer pipes for municipal and industrial wastewater, sewer pipes for storm water, water pipes and gas pipelines that are used to transfer fluids, often require repair due to leakage of fluids or destruction. Leakage may be directed from the environment to the interior or conductive portion of the piping. Alternatively, the leak may be directed outward from the conductive portion of the pipeline into the environment. In any case, it is advisable to avoid such a leak.

Leakage can be caused by improper installation of the original pipe, or the destruction of the pipe itself due to normal aging or due to the effects of corrosive or abrasive material. Cracks in or near pipe joints can be caused by environmental influences, such as earthquakes or the movement of large vehicles on top of surfaces, or similar natural or human vibrations, or other similar causes. Regardless of the reason, such a leak is undesirable and can lead to loss of fluid flowing inside the pipeline, or lead to environmental pollution and public health risk. If the leak continues, it can lead to structural failure of the existing pipeline due to loss of ground support and lateral support of the pipeline.

Due to the ever-increasing costs of labor, energy and equipment, it is increasingly difficult and less economical to repair underground pipes or sections of them that can leak, digging and replacing pipes. As a result, a variety of methods were invented for on-site repair or rehabilitation of existing pipelines. These new methods eliminate the costs and risks associated with digging and replacing pipes or pipe sections, as well as significant inconvenience to the public. One of the most successful repair or trenchless recovery processes currently in widespread use is the Insituform® process. This process is described in US Pat. Nos. 4,090,063, 4,064,211 and 4,135,958, all of which are incorporated herein by reference.

According to the established practice of the Insituform process (at the work site), an elongated flexible tubular insert made of felt fabric, foamed or similar resin-impregnated material with an external impermeable coating, which is impregnated with a thermosetting cured resin, is installed inside the existing pipeline. Typically, an insert is installed using the inside-out process described in the last two of these patents for the Insituform process. In the process of turning inside out, the pressure acting on the inner surface of the inside-out liner presses it against the inner surface of the pipeline and puts it into contact with it. However, the Insituform process is also accompanied by pulling the resin-impregnated liner into the pipeline with a rope or cable and using a separate fluid-tight inflatable balloon or liner, which are turned inside out inside the liner, causing the liner to cure on the inner wall of the existing pipeline. Such resin impregnated liners are commonly referred to as “field cured tubes” or “CIPP liners,” and their installation is called a CIPP installation.

Flexible tubular CIPP liners have an outer smooth layer of a relatively flexible, substantially impermeable polymer covering the outer side of the liner in its original state. When turned inside out, this impermeable layer is on the inside of the liner after the liner is turned inside out during installation. As the flexible liner is reinserted inside the piping, the piping is internally pressurized, preferably using a fluid to turn inside out, such as water or air, in order to press the liner radially outward to fit onto the inner surface of the existing the pipeline.

Usually, in order to provide the necessary static pressure in order to turn the liner or cylinder inside out, equipment is installed at the installation site for turning inside out. As an alternative, a module for turning inside out, shown and described in patents US 5154936, 167901 (with reference to No. 35944) and 5597353, the contents of which are incorporated herein by reference, are proposed. Curing can be initiated by introducing hot water into the inside-out liner through a recirculation hose attached to the end of the inside-turning liner. Inverting water is recycled through a heat source such as a hot water boiler or heat exchanger and returned to the inverted liner until curing is complete. In this case, the resin impregnated with the impregnated material is cured, forming a solid, tight-fitting rigid inner coating of the pipe inside the existing pipeline. The new liner effectively seals any cracks and eliminates damage to any segment of the pipe or pipe connection, which prevents further leakage both inward and outward of the existing pipeline. The cured resin also serves to strengthen the walls of the existing pipeline, which provides reinforced structural support for the environment.

The inside-out installation, which took a long time to build, required workers to be 30 feet (9 meters) above the ground, often near trees and electrical wires. This method was improved in a device that allowed the hydrostatic head to be created using a pinch valve during the Insituform process. The liner was fed into the upper part of the device and was pulled through a pinch valve with pressurized water. Water under pressure acted on the front of the liner, forcing it to invert (turn inside out) into the restored pipe. These small diameter pipe repair devices have been used for approximately fourteen years.

The main disadvantage of using these water-using devices is the quantity and availability of inverting water. In order to act on curing, the water should usually be heated from 55 ° F (13 ° C) to 180 ° F (82 ° C) and then cooled by adding additional water to 100 ° F (38 ° C) before being diverted to the appropriate disposal system.

This disadvantage can be eliminated by using air instead of water in order to create an inverting force. After the impregnated liner is completely inverted, it can then be cured with steam. Although water is needed to produce steam, the amount of water in the form of steam is only 5-10% of the amount required for water inversion, curing and cooling. This means that steam can be used even if water cannot be easily obtained at the work site. This sharp decrease in the amount of water is the result of higher energy that can be obtained from one pound (0.454 kg) of water in the form of steam versus one pound (0.454 kg) of heated water. One pound of steam condensing into one pound of water gives approximately 1,000 British thermal units (1,055.06 kJ), while one pound (0.454 kg) of water gives only one British thermal unit (1.05506 kJ) for each degree of drop temperature. These reduced water requirements plus the actual elimination of the heating cycle significantly reduce the cure cycle time and installation time.

Why, then, with this obvious advantage of using air inversion and steam curing, was industry in no hurry to abandon water inversion and curing with hot water?

When water is used to invert the resin impregnated liner, the non-inverted portion of the liner from the inverted nose to the inverting device is supported by a force equal to the amount of water displaced by the liner. In the case of a CIPP insert, this means that the effective value of the insert weight is significantly reduced, as is the force required to stretch the non-inverted insert forward to the inverting nose. When air is used to create an inverting force, the non-inverted liner lies at the bottom of the pipe and the pressure of the air acting on the inverted nose of the liner must pull forward the full weight of the liner.

In order to invert a CIPP liner, three forces must be overcome, regardless of what is used to create the inverting energy.

1. The force required to invert the liner (turn the liner inside out). This force varies depending on the thickness of the liner, the type of material and the ratio of the thickness of the liner to the diameter.

2. The force required to stretch the liner from the inverting device to the front of the invert.

3. The force required to pull the liner through the inverting device.

Force number 1 mentioned above is usually the same for both air and water inverts.

Force number 2 varies significantly for air and water and can limit the length of air inverts. There is a pressure limit that can be used to invert the liner without adversely affecting the quality of the installed CIPP liner and / or without damaging the existing pipeline. To reduce the required traction force for both water inversion and air inversion, grease can be used.

Strength number 3 may vary depending on the design of the device. In most devices currently in use, the force required to pull the liner through the device will increase with either or both forces increasing: number one and two. This is due to the fact that in order to increase the available invert energy, the typical device used today limits the loss of fluid under pressure from the high pressure chamber below the entry point of the liner into the device and the cuff and the bandaged end of the invertible liner. This limitation is usually achieved by increasing the air pressure in the pneumatic seal (i.e., the Insituform process CHIP module) or by using a seal that receives energy from an inverting fluid (i.e., Shooter seal ring). The movement inward in both cases is limited by the seal material and compression of the inverted CIPP liner. This in turn causes an increase in friction between the inverted CIPP liner and the seal.

In view of these obvious advantages of steam curing compared to curing with hot water, the use of steam energy has been proposed. Air inversion of an inflatable balloon and curing flow steam are described in US 6708728 and US 6679293 relating to the "Insituform" process, the contents of which are incorporated herein by reference. The processes disclosed in these patents use retraction and inflation technology and are currently used for small diameter liners. They provide advantages over water turning inside out for small diameters. In addition, the use of a perforating container disclosed in these patents is not suitable for medium and large diameter liners. Medium-sized liners are liners that are approximately between 18 and 45 inches in diameter (45.7 cm and 1.2 m). Larger diameters are those that exceed approximately 45 inches (1.2 m) or more in diameter.

Accordingly, it is desirable to provide an improved device for air inversion and an assembly for making holes for a CIPP installation with curing by flowing steam.

SUMMARY OF THE INVENTION

In accordance with the invention, there is provided a device for inverting (turning inside out) air of a liner impregnated with resin and cured at the place of use, having a low friction seal. Unlike other inverting devices used today, this adjustable seal of a predetermined shape after it is adjusted does not increase friction on the liner with increasing pressure of the inverting fluids. At the remote access point is a template and a hole making pipe having an outlet pipe with a hole making seal, comprising a hole making tool. After the inversion is completed, the hole making tool is inserted into the inflated liner and the outlet hose is attached.

The seal is formed by a gap gap adjustable at least in the direction of its thickness. The adjustment of the gap gap across is carried out by moving the rigid elements essentially perpendicular to the liner passing through the seal. The seal may have one fixed side and one movable, adjustable side. In this case, the fixed side has a steel base plate with a heat-resistant compressible layer of material with a thickness of ~ 1/4 inch (6.35 mm), such as elastic silicone rubber, and a thin absorbent layer of 1/8 inch (3.175 mm) or less, such like polyester felt facing an impervious liner layer. This allows you to apply lubricant to the surface of the inverted CIPP liner. In this embodiment, the adjustable side of the seal has a substantially rigid one-inch (2.54 cm) thick shaped block of polymer material, such as nylon or the like, coated with a similar compressible and absorbent layer. The shaped block has dimensions and shape especially for the size and thickness of the CIPP insert to be inverted. The shaped block may be an integral element or made of three or four sections depending on the size of the flat-laid CIPP insert to be installed. Each section has a separate adjustment bolt.

In another embodiment of the invention, the seal is formed by a plurality of opposing fingers located across the slotted gap in the device. Each finger is a pneumatic piston or rod mounted in a cylinder connected to an air line. The rods can be located on one side facing the stationary opposite side, or surround the liner on both sides.

In a preferred embodiment, the seal has one fixed side and one movable, adjustable side. The fixed side has a steel base plate coated with a heat-resistant compressible layer of ~ 1/4 inch (6.35 mm) thick material, such as silicone rubber, and a thin absorbent layer (1/8 inch (3.75 mm) or less) such as polyester felt for lubricating the surface of a CIPP liner. The adjustable side has nylon shaped blocks of nylon covered with a similar compressible and absorbent layer. The shaped block has dimensions and shape especially for the size and thickness of the CIPP insert to be inverted. Typically, inverted CIPP liners are made with layers that are sized for the end position. This means that prior to inversion, the layer with the largest circle is on the inside, and the coated layer of the smallest circle is on the outside. This leads to the fact that the inner layer has a folded region or a thick spot in the cross section of the liner. The compressible layers on each side of the seal adapt to this and any other non-uniform section of the liner. The folded area can move back and forth along the surface of the CIPP liner, therefore, not controlled adaptation to this change in the local thickness of the liner would be ineffective. The compressible layer that surrounds the CIPP liner is well suited to adapt to any local liner thickness regardless of its location. The limited area of increased friction caused by these thick spots helps to provide improved friction characteristics of this seal design.

Accordingly, an object of the invention is to provide an improved apparatus and method for inverting a CIPP insert by air.

Another object of the invention is to provide a device for air inverting a CIPP liner with an adjustable seal that does not increase friction on the liner when the pressure of the inside-out fluid increases.

An additional objective of the invention is to provide a device for air inversion of the CIPP liner and steam curing.

Another additional objective of the invention is to provide air inversion and steam curing of the CIPP liner, preventing the inverted liner from settling before steam curing.

Other objectives and advantages of the invention will be apparent from the following description.

Brief Description of the Drawings

For a more complete understanding of the invention should refer to the following description, considered in conjunction with the accompanying drawings in which:

figure 1 is a side view of the air inversion module in accordance with the invention;

figure 2 is a top view of the seal for sealing cured in the place of operation of the liner in accordance with the invention;

figure 3 is an enlarged top view of the seal of the air inversion module shown in figure 1;

4 is an enlarged top view of a seal having a segmented shaped block in accordance with a preferred embodiment of the invention;

5 is a side view of the device for air inversion and steam curing with a CIPP liner, ready for inversion in accordance with the invention:

6 and 7 are top views schematically showing a plurality of fingers of the seal of the device shown in FIG. 1 in the open and working position, respectively;

Fig. 8 is a sectional side view of an air inverter and steam curing device in accordance with the invention; and

Figures 9 and 10 are schematic views of an invertible in-place cured liner entering the template and pipe for making a hole, before and after making a hole with a tool.

The implementation of the invention

The following description discloses an improved device for air inversion and steam curing of a CIPP liner in accordance with ASTM F1216 Standard Practice for Rehabilitation of Existing Pipelines and Conduits by the Inversion and Curing of a Resin-Impregnated Tube (F1216 Standard Process for Restoring Existing Engineering Networks) and piping by inverting and curing the resin impregnated liner, published by the American Society for Testing Materials). The described device is well suited to carry out surface work through structures such as manholes for the restoration of existing underground utilities and pipelines.

Now turn to figure 1, in which a side view shows the module 11 air inversion and steam curing, designed in accordance with the invention. The module 11 is made of a rigid material, usually metal, such as steel or aluminum, and the like, and is sized to allow the impregnated cured liner to be passed through the module through the place of use. Composite materials or plastics can also be used, provided that they can withstand the internal pressures and temperatures that will be created during use.

The module 11 includes an essentially cylindrical hollow chamber 12 high pressure having an upper flange 13 and a lower flange 14. On the lower flange 14 is installed a hollow shoe 16 invert. The invert shoe 16 includes a truncated cone-shaped upper section 17 with a large hole 17a and a small hole 17b and an annular flange 18 for attaching the shoe 16 to the lower flange 14. This makes it possible to easily insert shoes of various diameters into the module 11. A small hole 17b of the truncated cone section 17 is connected to a substantially cylindrical retaining shoe 19 with external ribs 21 for attaching a folded rear portion of the insert 27 cured at the place of use supplied through it. The inversion shoe 17 is also equipped with an inlet pipe 20 for supplying air / steam.

The upper part of the high-pressure chamber 12 is closed by the upper cover 22 formed from the first semicircular section 23 and the second semicircular section 24. Both semicircular sections 23 and 24 are fixed to the upper flange 13 and face each other with cutouts 23a and 24a with the formation of a gap 26 between them to pass the liner 27 into the module 11. Details of the design of the slotted gap 26 forming the seal 28 so that sufficient pressure for inversion can be created in the high-pressure chamber 12 and in the shoe 16 will be described below.

Semicircular sections 23 and 24 with cutouts 23a and 24a are fixed to the upper flange 13, forming a gap gap 26 along the center line between them. The semicircular section 23 includes a horizontal portion 37 of the stationary seal holder 31 with a horizontal mounting portion 32, a substantially vertical section 33 in diameter of the pressure chamber 12 and an expanding portion 34. The semicircular section 23 includes cutouts 23a facing the semicircular section 24.

The corresponding adjustable semicircular section 24 also includes an adjusting holder 36 with a horizontal mounting part 37, a substantially vertical section 38 and an expanding part 39. The adjusting holder 36 also has a cutout 24a that forms a slotted gap 26 with the cutout 23a. The movable adjusting holder 36 is provided a cut-out 41 for mounting at least one rigid shaped block 42. The shaped block 42 includes an input cut-out 43 for the liner facing the vertical section 33 of the fixed holder 31. You cut 43 for the liner is made in the form of a recess in the shaped block 42. Three screws 44 are installed behind the shaped block 42 to change the position of the block 42 in order to adjust the slotted gap 26 so that the used insert is inserted into it.

Between both sections of the upper cover 22 and the upper flange 13 are two sheets of compressible member 46. The compressible material 46 is located along the facing surfaces of the holders 31 and 36 and is fixed to the expanding sections 34 and 39 of the holders. The compressible material 46 forms a smooth, compressible and resilient guide for the liner 27 in contact with the seal 28 when passing through it. On the side of the compressible material 46 facing the seal 28, there is an absorbent layer 47 of a material such as a felt layer that can be impregnated with a lubricant to lubricate the invertible liner 27. Alternatively, a layer can be used to facilitate the passage of the liner 27 through the seal 28 low friction material such as FEP, PFA or polytetrafluoroethylene. The use of compressible material 46 ensures that the seal 28 is clamped over the cross section and profile of the insert 27. Slit clearance screws 44 are installed on the adjustable holder 36 to move the shaped block 42 toward the opposite vertical section 33, adjusting the passage in the seal 28.

In the embodiment of FIG. 4, the shaped block 51 is formed of three separate segments including two outer sections 52 and 53 with curved cutouts 52a and 53a and a straight middle section 54. Here, the holder 36 includes separate pockets in which sections 52, 53 and 54 are installed with an aperture in the vertical section 38 of the holder, providing movement towards the fixed holder 31 while tightening the screws 44. The middle section (54) has a straight edge, while the outer sections 52 and 53 are curved Contours corresponding to the shape of the flat-laid the liner 27.

Module 11 includes three support mounting brackets 56 welded to the side wall of the high-pressure chamber 12 to secure the struts 57 holding the module 11 above the hole where the insert is inserted. Module 11 is made of hard metal material, such as steel or aluminum. Once assembled, the semicircular sections 23 and 24 with the shaped block 42 and compressible material 46 form an adjustable seal 28, which allows the liner 27 to pass through it with pressure when applying air pressure to the inlet pipe 20 for air / steam.

The shaped block 42 may be a single part, as shown in the embodiment of FIG. 2, or include three sections 52, 53 and 54, as shown in the embodiment of FIG. 4. Additional sections can also be made that provide greater flexibility when working in the area of the folds and when deviating the cross-sectional dimension of the insert 27 as it passes through the shaped block.

Compressible material 46 is a heat-resistant elastic layer of material with a thickness of ~ 3 to 20 mm, such as silicone rubber. A thin absorbent layer (2-8 mm) of polyester felt is located on the outer surface of the compressible layer 46 to apply lubricant to the surface of the CIPP liner 27. As noted above, a low friction material such as polytetrafluoroethylene canvas can be used instead of oil-soaked felt. . The seal 28 formed by the slotted gap 26 in the upper sections 23 and 24 can be stepless by using an embodiment having a plurality of pneumatically actuated fingers, as shown in FIGS. 6 and 7.

Module 11 is preferably designed to install a small diameter CIPP liner in an existing pipeline, using air to invert the liner and steam to cure it. Small diameter liners are those that have a diameter between approximately 6 and 12 inches (15 to 30 mm).

In order to use the module 11 to install a liner that is cured at the place of use by means of air inversion and steam curing, it is necessary to perform the following steps.

1. The adjusting screws 44 on the adjustable holder 36 of the seal 28 are unscrewed, and the moistened CIP-insert 27 is inserted through the seal 28 into the high-pressure chamber 12 and the retaining shoe 19. The edge of the insert 27 is turned back behind the edge of the retaining shoe 19 and secured with two stainless steel bandages . An air / steam hose is attached to the inlet pipe 20 on the inversion shoe 16.

A holding rope or cable is attached to the other end of the CIPP insert 27. Appropriate lubricant is applied to the absorbent layers 47 of the felt at the inlet of the module 11. The seal 28 is adjusted by adjusting screws (44 so that it closes evenly around the CIPP insert 27.

2. The air / steam line connects to the air / steam distributor to which the steam supply line and the compressed air supply line are connected. All air and steam connections are checked for the installation of safety pins or wrapping checks. After the pneumatic valve on the distributor is closed and the air supply regulator is set to the off position, preventing the passage of air, the compressed air supply line is connected to the compressor. The air discharge line in the compressor closes and the air compressor starts.

3. When the operator controlling the air / steam distributor has made sure that everything is safe and can be started, the operator opens the air / steam supply line to the air inverter and slowly turns the adjusting screw on the air supply regulator, increasing the compressed air supply until the desired air inversion pressure. The air inverter operator simultaneously pulls the CIPP insert from the insulated truck or hopper to insert the insert into module 11.

Inverting continues until the rear end of the liner approaches module 11. At this time, the holding rope passes along the rollers above the air inverter. Immediately before the end of the insert insertion into the air inverter, the holding rope is wound around the tension drum and tensioned.

As soon as the end of the liner passes the seal at the top of the air inverter, the seal is adjusted to reduce air leakage. The holding rope and the inverting air pressure are controlled in such a way as to maintain the same invert speed and pressure as those used in the first half of the invert process.

4. As shown in Figs. 9 and 10, in the back hatch of the trunk in which the liner is laid, a template is made of a rigid PVC or metal pipe equipped with an assembly 61 consisting of a pipe 62 and a steel pipe 63 and centered in this way to accept an inverted liner. As the inverted front of the liner approaches the far hatch, inversion slows down, allowing the insert to enter the template. Inverting stops when the front of the inverted liner extends approximately one diameter beyond the end of the mold.

The holding rope is untied, and a hole is made in the inverted liner by inserting a steel pipe 64 for making a hole with a piercing tip 66 located at its lower end and a valve 67 at its upper end. On the pipe 64 for making a hole, a flange or O-shaped band 68 is provided to prevent the pipe 64 from puncturing the opposite side of the liner.

The operator responsible for making the hole notifies the workers at the inverting end that he is preparing to make a hole in the inverted liner, so that they must be prepared to regulate the air supply in order to maintain pressure in the inverted liner after the hole is made in it.

After a hole has been made in the liner, the valve 67 on the hole-making pipe is closed, and an outlet hose with a valve at its distal end is connected to the pipe 64. Now control is done at the far end of the exhaust hose.

5. The exhaust valve and air inlet regulator are adjusted to maintain the desired flow rate, recommended heating and curing pressure. The steam boiler is purged and the steam supply hose is attached to the air-steam distributor. The distributor operator is notified that steam is being supplied to the air / steam distributor.

The air / steam distributor operator notifies the far end personnel that warm-up is starting. The temperature of the interface is recorded at 6 o’clock in the far hatch. The warmed air-steam mixture should have a temperature of approximately 180 ° F (82.2 ° C). Warming up continues until there is no increase of 3 ° F (1.8 ° C) on the inner surface in the far hatch.

6. After warming up is complete, airflow is slowly reduced, and solid vapor (no air) is used to maintain the recommended curing pressure. Solid steam curing continues for approximately 1 hour, with internal surface temperatures recorded at 15-minute intervals. And if an internal surface temperature of 130 ° F. (54.4 ° C.) takes place for at least 30 minutes from 1 hour of curing, then curing is completed. Otherwise, cure continues until a temperature of 130 ° F. (54.4 ° C.) is maintained for at least 30 minutes.

7. After the curing cycle is completed, the steam is slowly turned off, while air is simultaneously added. During cooling, the curing pressure must not be exceeded. The liner is cooled for at least 15 minutes or until the interface at the far end reaches a temperature of 130 ° F (54.4 ° C), whichever is longer. Then the steam supply in the steam boiler is turned off. When the pressure in the supply hose from the steam boiler reaches zero, the steam supply hose is disconnected from the distributor. When cooling is complete, before disconnecting the compressed air supply hose from the distributor, the air compressor is turned off and the pressure in the air hose is released.

Depending on the particular type of resin with which the liner is impregnated and its thickness, when the curing is completed, the steam flow is turned off, while the air flow is regulated so as to maintain the curing pressure. The exhaust valve is set when cooled to approximately 130 ° F (54.4 ° C) at the 6 o'clock position for at least one hour.

After the temperature has dropped to the required level, the air flow pressure drops to zero, the exhaust valve opens completely. Any condensate that may have collected in the cylinder is removed by drainage on the “outlet” assembly.

In this case, to remove the ends from the pipe with the liner and resume service using standard procedures, follow the procedures for entering an enclosed space.

A flexible field-curable liner is of the type generally well known in the art. It is formed from at least one layer of flexible resin impregnated material, such as a felt layer having an outer layer of an impermeable polymer film. The felt layer and the film layer are sewn along the seam line, forming a tubular liner. To ensure the tightness of the liner, a compatible thermoplastic film in the form of a tape or extruded material is placed or extruded onto the seam line.

For large diameter liners, several layers of felt material may be used. Felt layers can be natural or synthetic flexible, resin-absorbing materials, such as polyester or polyacrylonitrile fibers. The impermeable film in the outer layer may be a polyolefin, such as polyethylene or polypropylene, a vinyl polymer, such as polyvinyl chloride, or polyurethane, which is well known in the art. At the initial stage, in all installations for trenchless restoration, the existing pipeline is prepared by cleaning and filming.

Before starting installation in accordance with the method according to the invention, the felt of the liner is impregnated with a curable thermosetting resin using a process called "soaking". The soaking process typically involves injecting resin into the felt layer through an edge or hole formed in the impermeable film layer, creating a vacuum, and passing the impregnated liner through the pinch rollers, which is well known in the liner technology. One such procedure for this vacuum impregnation is described in US Pat. No. 4,366,012 relating to the Insituform process, the contents of which are incorporated herein by reference. A wide variety of resins, such as polyester, vinyl alcohol esters, epoxies, and the like, which can be used according to specific requirements, can be used. It is preferable to use a resin that is stable at room temperature, but which cures easily when heated.

You can see that the device according to the invention easily allows you to achieve the benefits of curing the liner with the resin by means of flowing steam. In the practical implementation of this process, the liner can be easily turned inside out inside an existing pipeline. Using a low friction seal on the chamber to turn inside out, you can increase the pressure without increasing friction on the moving liner. Then, steam having a higher energy for curing the resin than circulating hot water is passed through a curable liner.

On Fig shows the module 110 air inversion, made in accordance with another embodiment of the invention. Module 110 includes a rectangular tray or container 111 mounted on a frame 112 above the passage to the pipeline in which the liner is to be installed. A roll 113 is located at the top of the frame 112 above the container 111 to facilitate the feeding of the resin impregnated liner 116 into the container 111. The upper part of the container 111 is partially closed by a pair of opposing plates 121 and 122 forming a gap gap 123 between the side walls of the container 111a and 111b. The bottom of the tank 111 is sealed and has an invert nipple or shoe 131 in the lower part for fastening an invertible insert 11 around it. An invert chamber is formed between the upper and lower parts of the tank 111. An inlet 132 is provided on the side of the vessel 111 for supplying air and steam from a compressed air supply line and a steam line 134 to the invert chamber. The size of the container 111 is selected so that the flat-folded liner 116 does not occupy the full width of the gap gap 123. This ensures that air and steam can freely flow around the entire perimeter of the liner, moving it through the invert shoe 131.

The slit gap located on top bends around the elastomeric sheet 46, in the bend 136 of which there are a plurality of fingers 137 partially covering the slit hole 123, as shown schematically in Figs. 6 and 7. This allows the flat-folded liner 116 to pass through the slit gap 123 and the fingers 137 , close the gap gap 123 at the edges of the liner, as is schematically shown in Fig.7.

The fingers 137 are rigid rods 133 mounted in cylinders 138 connected to the air line 139, as shown in FIG. The line 139 has a bleed air valve and a pressure gauge 141 and a pressure relief valve 142. At the end of each rod 133, there is a rigid ring 146 approximately 1-3 cm in diameter and in contact with the back surface 127 of the bent elastomeric sheet 46. Each finger 137 is positioned so that the ends of the rings 146 form a continuous profile around the liner 116 and cover the unoccupied portion gap gap 123 in the tank 111.

The elastomeric sheet 46 is a heat-resistant compressible layer of material with a thickness of ~ 3 to 20 mm, such as silicone rubber with a thin absorbent layer (47) of 2 to 8 mm, such as polyester felt, to apply lubricant to the surface of the CIPP liner 116. Fingers 137 are located behind both sides of the elastomeric sheet 46 to press it and the felt 47 against the opposite sides of the CIPP insert 116. Typically, the CIPP inserts intended for inversion are made with layers sized for the end position. This means that prior to inversion, the layer of the largest circle is on the inside, and the coated layer of the smallest circle is on the outside. This leads to the fact that the inner layer has a folded region, i.e. thick spot in the cross section of the liner. The fingers 137 on each side of the slotted gap 123 adapt to this and any other non-uniform cross-section of the liner 116. The folded area can also move back and forth along the surface of the CIPP liner 116, and the fingers 137 with adjustable stroke adapt to local changes in thickness.

In the illustrated embodiment, the device 110 includes 64 fingers 137, 32 on each side of the slit gap 123. It is contemplated that any number of fingers 32 to 128 may be used, with rings that are 1 to 5 cm in size. diameter. Obviously, the smaller the size of the ring, the more fingers that can be included in the structure and the more subtle changes in the shape or profile of the gap gap are possible. However, note that the rings may pierce the impermeable coating of the liner. The rings should not be too large to form gaps at the edges of a flat-folded liner or in zones of variation in its thickness.

The invert shoe 131 is elongated in order to install a flat-folded liner 116 therethrough extending through the container 111 and has ribs or edges for installing steel bandages to secure the liner 116. Clamping bars are provided for attaching the liner 116 to the elongated sides of the invert shoe 131.

The installation procedure using the inverter module 110 is identical to the procedure described for the previously described embodiment of the invention using the inverter module 11.

Thus, the tasks set above, from those that became apparent from the previous description, are effectively solved and, since some changes can be made to the implementation of the above method and the above construction, without going beyond the scope and essence of the invention, it is assumed that all material contained in the above description and shown in the accompanying drawings should be interpreted as illustrative and not in a restrictive sense.

It should be understood that the following claims are intended to cover all the generic and specific features of the invention described herein.

Claims (12)

1. A device for air inversion and steam curing for installation of a resin impregnated tube liner, cured in the place of operation, containing
a rigid container having dimensions that allow the impregnated liner to be cured in the place of operation to pass through and forming an invert chamber, which is provided with a gap in the upper part and an invert shoe in the lower part, as well as an air and steam inlet;
compressible material located on both sides of the slot gap, which is adjustable in the direction perpendicular to the liner when it is moved through the slot gap into the container and invert from the inversion shoe, while
the container is equipped with a plurality of movable fingers located at least on one side of the slotted gap to adjust it and pressed against the liner passing through the slotted gap. 2. The device according to claim 1, in which the container is essentially cylindrical, and the invert shoe has the shape of a truncated cone. 3. The device according to claim 1, in which the container is made of metal. 4. The device according to claim 1, in which the compressible material is an elastomeric material. 5. The device according to claim 4, in which the elastomeric material is an organosilicon rubber. 6. The device according to claim 1, in which a plurality of movable fingers located at least on one side of the gap gap are installed with the possibility of pressing the compressible material to the liner passing through the gap gap. 7. The device according to claim 1, in which each finger is made in the form of a pneumatic piston or rod located in a cylinder connected to a highway located near the slot gap. 8. The device according to claim 1, comprising a layer of absorbent material on the surface of the compressible material with the possibility of contact with the liner, as it passes through the slotted gap. 9. The device according to claim 1, in which the number of movable fingers is from 16 to 64 on each side of the slotted gap. 10. The device according to claim 8, in which the compressible material is silicone rubber, and the absorbent layer is felt. 11. The device according to claim 1, in which each finger is a rod mounted in a pneumatic cylinder, and provided at the end with a ring for pressing the elastomeric sheet to the liner. 12. The device according to claim 1, in which the container is made essentially rectangular, and the inversion shoe has a conical shape, which allows bending of the liner and securing it to the shoe.

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