JPH05280A - Method for cleaning pipe - Google Patents

Abstract

PURPOSE:To shorten a cleaning execution time by omitting the drying work of the inner surface of a pipe due to hot air after grinding work when the pipe is cleaned by passing gas such as compressed air containing a grinding material through the pipe in order to remove the rust or other substance bonded to the inner surface of the pipe such as a water pipe or a gas pipe. CONSTITUTION:The gas such as the compressed air from a compressor 19 is heated by a heater 21 and the grinding material 14 from a tank 15 is heated by a heater 22 and the mixed stream of the heated gas and the heated grinding material 14 is sprayed to the inner surface of a pipe P from a nozzle 2 and moved to clean the inner surface of the pipe P.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe cleaning method for removing various deposits such as water, gas, and other rust or scale on the inner surface of the pipe.
More specifically, the present invention relates to a cleaning method suitable for a pipe having a large diameter, which makes it possible to further shorten the construction time when cleaning is performed by passing a gas containing an abrasive into the pipe.

[0002]

2. Description of the Related Art Pipelines such as various large-diameter pipes, water mains, gas mains, etc. start to oxidize in a few years, and after 10 years have been corroded, and water pipes are rusted. If red water begins to come out, and if it deteriorates further, holes will occur in the pipes, leading to water leaks and gas leaks, which will cause the problem of having to replace the entire pipe.

Therefore, various cleaning methods are carried out as a method of cleaning the pipe for removing the rust formed on the inner surface of the pipe or various deposits to restore the function of the pipe to the original state by rehabilitating the pipe. Further, a pipe lining construction method such as applying a quick-drying epoxy resin paint to the inner surface of the cleaned pipe is performed.

As a method for cleaning the pipe, a scraper construction method in which a blade (scraper) in contact with the inner surface of the pipe is moved to scrape off rust, or 200 to 250 kg / cm ² of pressure water is sprayed onto the inner surface of the pipe by a special high pressure pump There is a water jet method that removes "rust rust" and advances the nozzle, and an air sand method that removes "rust rust" by injecting a high-pressure, high-speed air flow (turbulent flow) with the abrasive on the inner surface of the pipe. . Further, in passing an air flow containing an abrasive through a pipe, the method of the Japanese Patent Publication No. 57-5420
As disclosed in Japanese Patent Publication No. 9, a method is known in which, in order to accelerate the gas flow in contact with the inner surface of the pipe, a speed increasing member forming a gap with the inner surface of the pipe is cleaned while moving in the pipe. . Furthermore, exclusively for large diameter pipes,
A method combining the scraper method and the air sand method is used.

Further, the present applicant has previously filed Japanese Patent Application No. 62-292.
No. 837 (Japanese Patent Laid-Open No. 13557/1989), a cutter is provided symmetrically with a nozzle rotating in the circumferential direction so as to be balanced, and is compressed together with an abrasive from the nozzle toward the inner surface of the pipe toward the rotation direction side of the nozzle. While jetting air in a reverse jet state, we proposed a device that can move forward while scraping the inner surface of the pipe with a cutter to strongly remove rust and rust on the inner surface of the pipe and polish the inner surface.

In order to clean a pipe using the above-mentioned air sanding method or a method combining the air sanding method and the scraper method or the above-mentioned apparatus proposed by the applicant of the present invention, for example, in the pipeline of a water main, In such a case, first drain the water and then use a blower heater at 80 ° -10
After hot air of 0 ° C is passed through the pipe to dry the inner surface of the pipe, sand is supplied to the compressed air flow from the compressor to polish the inner peripheral surface of the pipe to remove rust and other deposits. The foreign matter is scraped off from the end of the pipe opposite to the compressed air feeding side by suction, and is sucked into the external dust collector.

In this case, after finishing the polishing work, in order to dry the fine dust adhering to the inner surface of the pipe in the wet state and store it in the dust collector, usually hot air at 60 ° C. is passed through the pipe for about 3 hours to get inside. After drying, the heater of the blower is turned off and the blower is operated for about 1 hour to remove dust on the inner surface of the pipe and collect dust to complete the cleaning operation. After that, a lining method for the inner surface of the pipe is carried out if necessary.

[0008]

As a method for cleaning pipes, the scraper method has the advantage of being able to handle all pipe diameters, but since the work is done while washing with water, the problem of water treatment remains, and the water jet method is Although it is suitable for use in small diameter pipes, it also has the problem of water treatment because it is a wet type. Further, since the air sand method and the above-mentioned method mainly based on this method have a merit that there is no problem of water treatment and the post-treatment is easy because they are a dry method, since the drying work is required as described above, the construction time is reduced. You can't get faster than that.

The present invention has been made in view of the above points, and an object of the present invention is to provide a novel method capable of simplifying the post-treatment, accelerating the construction speed, and shortening the construction time.

[0010]

In order to achieve the above object, in the method for cleaning a pipe of the present invention, as a method for cleaning a pipe containing a gas containing an abrasive, at least an abrasive is used in advance. A gas such as compressed air is heated, and the heated gas containing the abrasive is blown onto the inner surface of the pipe for cleaning.

When heating the above-mentioned abrasive and a gas such as compressed air, it is effective to individually adjust the temperature and heat the gas.

[0012]

When the hype is cleaned by the method configured as described above, at least the gas such as the abrasive and the compressed air is heated in advance so that the gas containing the heated abrasive is blown and moved to the inner surface of the puff. By polishing the inner surface of the pipe with a hot air, the dry operation of the inner surface of the pipe with hot air before the polishing operation of passing compressed air or other gas containing abrasives through the inner surface of the pipe is sufficient. Only the surface of the adhered substance can be dried, and the thick part where the inside is kept in a wet state is permeated to the inside by the blowing action of the heated abrasive and the gas such as heated compressed air to dry. At the very least, the polishing operation can be performed, and the polished inner peripheral surface of the pipe can be dried. Therefore,
The working time for drying with hot air from the blower heater after polishing (usually about 3 hours) can be omitted, and the cleaning work can be performed only by the dust collection function of the fine dust adhering to the inner surface of the pipe due to the non-hot air blowing. You can finish it.

When the abrasive and the gas such as compressed air are heated separately, the temperature is controlled separately, and the inner surface of the pipe is dried efficiently and efficiently in response to the condition of rust and other deposits on the inner surface of the pipe. It can be done.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side view schematically showing a cleaning device for carrying out the pipe cleaning method of the present invention as a partial cross section, where P indicates a pipe having a relatively large diameter to be cleaned, The length is shown short for convenience (usually the span of a pipe is 80m to 100m for a water main). This pipe P is for cleaning by forming vertical shafts 31 and 32 on both sides and disconnecting it from the other, and an adhered matter 33 such as rust and scale is adhered to the inner surface. Reference numeral 2 is a single nozzle for discharging compressed air and an abrasive, which is provided so as to face the inner wall surface of the pipe P slightly obliquely and to rotate in the circumferential direction. The hollow rotary shaft 1a provided with the nozzle 2 is
The rotating device main body 1 is provided so as to be driven to rotate by a motor 10. For the rotating device main body 1, compressed air passes from a compressor 19 through a pipe 20, a hose winding device 17, and the hose winding device. Hose 12 that can be wound around
As supplied from the vertical shaft 31, the hose 12 is guided by the guide roller 8a of the pipe mounting jig 8 through the guide hole 8b and is connected to the hollow rotary shaft 1a. The hose 12 is compressed by the rotating nozzle 2. The abrasive material 14 described later is ejected together with the air.

In the main body 1 of the rotating device, a sled body 4 which is a three-positioning member is formed by dividing the circumference into three equal parts on the outer peripheral portion thereof. It is provided so as to be slidable in the axial direction of the pipe by being pressed against the inner surface, and the axis of the hollow rotary shaft 1a is located on the axial line of the pipe P (see FIGS. 2 and 3).

The compressed air and abrasive discharging nozzle 2 is obliquely attached to the outside of the hollow rotary shaft 1a toward the forward side in the axial direction of the pipe and at the side of the rotary shaft 1a in the rotational direction (FIG. 3). In the case of so-called reverse injection from the opening of the nozzle 2 toward the rotational direction (clockwise direction) when the hollow rotary shaft 1a is rotated, one is provided in the oblique direction on the clockwise direction). A mixed flow of compressed air and an abrasive is strongly blown to the inner wall surface of the pipe P. Further, the hollow rotary shaft 1a is provided with a cutter 11 symmetrically with respect to the nozzle 2 and the hollow rotary shaft 1a.
Nozzle is provided at the tip of flexible elastic bar 11a that is obliquely planted in 1a, is biased outward by its own elasticity, and has an appropriate weight to balance the rotation when the shaft rotates. Is uniformly rotated and rubbed against the inner wall surface of the pipe P to remove the deposit. Further, when the abrasive material is heated and sent to the nozzle 2 as described later, a heater 22a is attached to compensate for the temperature drop of the heated abrasive material, and the abrasive material is heated at a predetermined heating temperature. It is supposed to be sprayed.

On the other hand, a guide ball 6 is rotatably connected to the end of the hollow rotary shaft 1a provided with the nozzle 2 on the side opposite to the hose 12 via a universal joint 5, and the wire is attached to the guide ball 6. The wire 7 connected to the pipe P is penetrated through the mounting jig 9 mounted on the end of the pipe P, guided by the guide roller 9a attached to the jig to the upper side of the vertical shaft 32, and wound on the winch 18. It is configured. By using the wire 7 on one side through the guide ball 6 for this nozzle movement, it can be used without trouble even in a place where there are many bent pipes. The wire penetrating portion of the pipe mounting jig 9 penetrates a rubber plate 9b of a predetermined thickness attached so as to close a hole having a diameter larger than the wire diameter, and the wire can move in a close contact state. It is like this.

In the middle of the pipe 20 from the compressor 19 on the nozzle 2 side, the abrasive material 14 made of sand or the like supplied from the openable / closable tank opening 16 of the abrasive material storage tank 15 is injected from the tank 15. A lower discharge pipe of the tank 15 is connected so as to supply the abrasive 14 to the compressed air flow. Further, in order to separately heat these abrasives and compressed air by adjusting their respective temperatures, the outer wall portion of the tank 15 is connected to the discharge pipe portion lower than the middle height of the tank and the inside of the tank. Heater 22 to heat abrasive material 14
However, heaters 21 for heating the compressed air from the compressor 19 are arranged at predetermined portions of the pipe 22 extending from the compressor 19 to the hose winding device. The heater 22 for heating the abrasive material and the heater 21 for heating the compressed air are transmitted to the temperature control panel from the generator 25 through the wiring 28.
It is possible to control the temperature individually via 13. As a result, an appropriate temperature is set for each of the rust and other deposits on the inner surface of the pipe to be cleaned, and the inner surface of the pipe can be efficiently dried during the polishing operation.

In the above, the hose winding device 17 and the winch
18 is driven by electric power transmission from a generator 25 through wirings 26 and 27, respectively, and the hose drum of the hose winding device 17 and the wire drum of the winch 18 cause the device portion including the nozzle 2 to be piped at a constant speed. The inside of the pipe P can be moved forward or backward, and the rust and other deposits removed in the paif P are connected to the upper opening of the device jig 8 located on the hose guide side at the end of the pipe P and are rotated. The blower 23 located on the main body 1 side blows the air into the suction dust collector 24 connected to the upper opening of the other mounting jig 9.

The blower 23 and the suction type dust collector 24 are driven by power transmission from the generator 25 through the wirings 29 and 30, respectively, and the blower 23 has a built-in heater 23a for blowing air and is introduced into the pipe P. Hot air (80 ° to 100 ° C) when drying the inner surface of the pipe at the beginning of cleaning work and when polishing the inner surface of the pipe with a mixed flow of compressed air and abrasives.
After finishing the polishing, the heater is de-energized and only the air is blown.

Next, the pipe cleaning work using the method of the present invention will be described.

First, the vertical shafts 31 and 32 are excavated on both sides of a pipe P of a main water pipe (usually 80 m to 100 m long) to be cleaned, and then draining of the pipe P is completed. Next, the pipe mounting jigs 8 and 9 are connected to both ends of the pipe P with the main body 1 of the rotating device equipped with the nozzle 2 for discharging compressed air and abrasives and the guide balls 6 inserted into the pipe P at predetermined positions. Blowers and other required connections are made to the mounting jigs 8 and 9. Set the heater 23a of the blower 23 to the heating state and keep it at 80 ° for about 3 hours.
Hot air at -100 ° C is passed through the pipe P to dry the inner surface of the pipe P. Next, the heater 22 for heating the abrasive material and the heater 21 for heating the compressed air are energized to bring them into a heated state, respectively. In response to the state of rust and adhered matter on the inner surface of the pipe P,
In consideration of passing the heated abrasive or compressed air through the hose 12, the temperature adjusting device 13 is operated to set an appropriate temperature, for example, 50 ° C. for the abrasive and 60 ° C. for the compressed air.

After the work of drying the rust on the inner surface of the pipe and the surface of other deposits is completed, the compressor 19 is operated to supply the heated abrasive 14 to the heated compressed air flow, the nozzle 2 is rotated, and the winch 18 is rotated. The wire 7 is driven and the nozzle 2 is advanced to polish the inner surface of the pipe. During this polishing operation, the blower 23 continuously blows hot air into the hype. “Rusty lumps” and deposits 33 on the inner surface of the pipe that are thick and have only the surface in a dry state and the inside is in a wet state are mixed flow of the abrasive and compressed air that are heated while being rolled up by the cutter 11. Thus, the dust in the dried state, which has penetrated to the inside and is dried, is prevented from adhering to the inner surface of the pipe P, is sucked, and is housed in the suction type dust collector 24. In this way, the polishing operation with the abrasive is completed by the forward movement of the nozzle 2 while rotating.

Next, the heater 23a of the blower 23 is de-energized, heating is stopped and air is blown for about 1 hour to remove the dry fine dust remaining on the inner surface of the pipe, and the cleaning work is completed. After the cleaning work is completed, the inner surface of the pipe will be lined if necessary.

In carrying out the method of the present invention, the above-mentioned embodiment is used as a pipe cleaning device in Japanese Patent Application No. 62-292837 proposed by the present applicant (Japanese Patent Laid-Open No. 13557/1989).
No.) has been used to clean a pipe. However, in any cleaning device, the device supplies an abrasive to a compressed air flow and a mixed flow of the compressed air and the abrasive causes the internal surface of the pipe to move. For the polishing work, the pipe cleaning work efficiency can be similarly increased by using the method of the present invention. Further, as an example, the pipe to be polished is a water main, and the case where compressed air is used as a gas to form a mixed flow with an abrasive has been described, but depending on the type of the pipe to be polished, for example, a pipe through which oil passes. It is also possible to use other nonflammable gases such as nitrogen gas.

If the pipe is cleaned by using the method of the present invention as described above, the drying operation by hot air which is conventionally required for drying the fine dust adhering to the inner surface of the pipe without drying after the polishing operation is omitted. It is possible to contribute to the reduction of construction time.

[0028]

According to the first aspect of the present invention, when cleaning a pipe (particularly a large-diameter pipe), at least an abrasive to be sprayed on the inner surface of the pipe and a gas such as compressed air are preheated. By doing so, it is possible to omit the drying work with hot air after polishing the inner surface of the pipe, it is possible to greatly shorten the construction time required for cleaning work, and in the case of cleaning work of water mains The effect is large, such as shortening the time.

According to the second aspect of the present invention, the abrasive and the gas such as compressed air are separately temperature-controlled and heated, so as to correspond to the state of rust and other deposits on the inner surface of the pipe. The inner surface of the pipe can be polished and dried efficiently.

[Brief description of drawings]

1 is a schematic side view of a partial cross-section of a cleaning device during the implementation of the method of the invention,

2 is a schematic side view of an enlarged partial cross section of the main part of the apparatus of FIG.

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

[Explanation of symbols] 1 Rotating device body 1a hollow rotating shaft 2 Nozzles for discharging compressed air and abrasives 5 Universal joint 6 guide balls 7 wires 8 Pipe mounting jig 9 Pipe mounting jig 11 cutter 12 hose 13 Temperature control panel 14 Abrasive 15 Abrasive storage tank 17 Hose winding device 18 winch 19 Compressor 20 piping 21 Heater for heating compressed air 22 Heater for heating abrasives 23 Blower 23a blower heater 24 Suction dust collector 33 Rust and other deposits P pipe

Claims (2)

[Claims] 1. A method for cleaning by passing a gas containing an abrasive through a pipe, wherein the abrasive and a gas such as compressed air are heated at least in advance, and the gas containing the heated abrasive is piped. A method for cleaning a pipe, characterized in that cleaning is performed while spraying and moving the inner surface. 2. The heating of the abrasive and a gas such as compressed air
The pipe cleaning method according to claim 1, wherein the temperature of each pipe is adjusted separately and the heating is performed.