JPS6319753B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a method for inserting a string-like object into long pipes such as gas pipes, water pipes, underground pipes such as power lines and communication cables. It is. These pipes are typically lined, cleaned,
When inspecting the inner surface condition or inserting power lines, etc., insert a string-like object such as a string, rope, wire, wire, or belt to serve as a guide prior to these operations. It is widely practiced to insert or pass other objects through a shaped object.

However, it is extremely difficult to initially insert a string-like object into these long tubes. Once a string-like object is inserted into a tube, anything can be done with that string-like object from then on, but the first string-like object to be inserted has nothing to guide it. Since there is no such thing, the work of inserting the first string-like object is
The aspect of the work is completely different from once the string-like object has been inserted.

If the tube is relatively short and has few bends, it is possible to insert a metal wire or steel strip into one end of the tube and use it as an initial guide, but if the tube is long (several hundred meters) or has many bends, Not applicable to pipes. In addition, various self-propelled devices have been proposed, but their use is limited due to their complex structures, inability to pass through curved sections, and inability to apply to vertically extending pipes. It was hot. Furthermore, if these devices were to stop in the middle of a pipe for some reason, it would not be possible to remove the device and the entire pipe would become unusable.

BACKGROUND ART In recent years, as a relatively easy method for inserting a string-like object into a tube, a flexible plastic cylindrical film is inserted into the tube while being turned over using fluid pressure, a string-like object is connected to this, and the above-mentioned A method has been proposed in which a string-like object is inserted into a tube by pulling out a cylindrical film.

Furthermore, as an improvement to this method, as in the invention of the previously filed Japanese Patent Application No. 53-62569, a string-like elongated object is connected to the free end of the cylindrical film, and the cylindrical film is turned over. This string-like elongate object is also inserted into a cylindrical film, and the string-like elongate object bears the force when the cylindrical film is pulled out.

Problems to be Solved by the Invention However, when pulling out the inserted cylindrical film, the contact area between the cylindrical film and the inner surface of the tube is large. requires a considerable amount of force,
The film was often scratched or cut by rubbing against the inner surface of the tube. In addition, the inserted cylindrical film is twisted to reduce the contact area with the inner surface of the tube, but fluid is partially sealed in the middle of the twisted cylindrical film and remains. This makes them more likely to be rubbed, and even more likely to break.

Furthermore, in the invention of Japanese Patent Application No. 53-62569, it is the cylindrical film that comes into contact with the inner surface of the tube and is rubbed, and when the cylindrical film is broken, the string-like elongated object is moved into the broken cylindrical shape. Since the inside of the film is transparent, it is difficult to completely pull out the cylindrical film.

Based on these circumstances, the inventors conducted a detailed study on the force exerted when pulling a cylindrical film from a tube, and found that if the cylindrical film is pulled out with the fluid remaining inside it when it is turned over. They discovered that the frictional resistance between the tube and the cylindrical film was large, making it easy to break.

The present invention has been developed in view of the above circumstances, and it is possible to completely remove the fluid from the inside of a cylindrical film inserted into a tube, and then pull out the cylindrical film from the inside of the tube, with a small force. It is an object of the present invention to provide a method by which a cylindrical film can be easily pulled out without breaking it.

Means for Solving the ProblemsThe first invention of the present application fixes one end of a flexible, airtight cylindrical body in an annular shape, applies fluid pressure to the rear part of the annular fixed part, and applies fluid pressure thereto. At the folded part that is formed, the flexible cylindrical body is inverted so that the inside becomes the outside, and the folded part is advanced from one end of the tube to the other end, and at one end of the tube, the tube and the inverted flexible cylindrical body are Each of the flexible cylindrical bodies is closed, and at the other end of the tube, the end of the tube is squeezed, and the end of the inverted flexible cylindrical body is narrowly squeezed, and the tube and the flexible tube are removed from one end of the tube. A pressure fluid is introduced between the flexible cylinder and the flexible cylinder to crush the flexible cylinder in its radial direction, and the fluid inside the flexible cylinder is discharged from the other end. The second invention is characterized in that the flexible cylindrical body is pulled out from the tube and the string-like object coupled to the flexible cylindrical body is drawn into the tube. One end of the body is fixed in an annular shape, a string-like elongated object is connected to the other end, fluid pressure is applied to the rear part of the annular fixed part of the flexible cylindrical body, and the folded part formed there While inverting the flexible cylindrical body so that the inside becomes the outside, the folded portion is advanced from one end of the tube to the other end, and as the flexible cylindrical body is turned over, the inverted flexible tube is The string-like elongated object is inserted into the shaped body, and the tube and the inverted flexible cylindrical body are respectively closed at one end of the tube, and the end of the tube is squeezed at the other end of the tube to make the inverted flexible cylindrical body. The end of the flexible cylindrical body is narrowed, and pressure fluid is sent between the tube and the flexible cylindrical body from one end of the tube to crush the flexible cylindrical body in its radial direction. The flexible cylindrical body and the string-like elongated object inserted into the flexible cylindrical body are brought into close contact with each other, and the fluid inside the flexible cylindrical body is discharged from the other end. The method is characterized in that the flexible cylindrical body is pulled out of the tube along with the string-like long object inserted into the flexible cylindrical body, and the string-like object coupled to the flexible cylindrical body is drawn into the tube. It is something.

The present invention will be explained below with reference to the drawings. The drawing shows the first invention of the present application, and 1 is a tube through which a string-like object is inserted. 2 is a storage container, and an airtight flexible cylindrical body 4 is wound around a reel 3 provided in the center thereof in a flat folded state. The flexible cylindrical body may be a flexible plastic cylindrical film, or may be a thin cylindrical fabric with a flexible rubber or plastic film attached to the outer surface. Further, the diameter of the flexible cylindrical body 4 may be larger than the inner diameter of the tube 1, and is not particularly limited, but preferably has an outer diameter that is approximately the same as the inner diameter of the tube 1. .

The storage container 2 is provided with a discharge port 5, and the flexible cylindrical body 4 has an annularly fixed distal end to the distal end of the discharge port 5. 6 is a pressure fluid inlet.

FIG. 1 shows the state in which the method of the invention is ready to be carried out, in which the flexible cylindrical body 4 is attached to a pressure vessel and the outlet 5 of the pressure vessel is connected to one end of the tube 1. is forced to confront.

When a pressure fluid such as air is fed into the pressure vessel 2 from the pressure fluid inlet 6 in this state, the rear part of the annular fixed part of the flexible cylindrical body 4 is pressurized, and a folded part 7 is formed there. Ru. At the folded portion 7, the flexible cylindrical body 4 is turned over so that the inside becomes the outside, and the folded portion 7 is pushed out from the discharge port 6. When this folded portion 7 is guided to one end of the tube 1, the flexible cylindrical body 4 is turned over at the folded portion 7, and the folded portion 7 advances inside the tube 1 as shown in FIG.

Then, when the folded portion 7 reaches the other end of the tube 1, the flexible cylindrical body 4 is turned over over its entire length,
As shown in FIG. 3, the flexible cylindrical body 4 is inserted into the tube 1.

Next, as shown in FIG. 4, one end of the tube 1 is closed with a lid 8, and the tip of the turned-over flexible cylindrical body 4 is closed and held by the lid 8. Also, this lid body 8
A pressure fluid inlet 9 is provided in the holder. Further, a different diameter joint 10 is fixed to the other end of the pipe 1, and a flexible cylindrical body 4 is inserted into a through hole 10' in the center of the different diameter joint 10.
The tip is squeezed and inserted. The tip of the flexible cylindrical body 4 may simply be passed through the varying diameter joint 10 as shown in the drawing, but it is preferable to fold the tip back outward and cover the outer periphery of the varying diameter joint 10.
In particular, when the diameter of the flexible cylindrical body 4 is much smaller than the inner diameter of the tube 1, the tip of the flexible cylindrical body 4 is folded back and placed over the tip of the varying diameter joint 10, and the tube 1 and the flexible tube are Preferably, leakage of fluid between the body 4 and the body 4 is prevented.

Next, when a pressure fluid such as air is introduced between the pipe 1 and the flexible cylindrical body 4 from the pressure fluid inlet 9,
As shown in FIG. 5, the flexible cylindrical body 4 is pressed flat from one side by fluid pressure, and the fluid inside the flexible cylindrical body 4 is squeezed by the flexible joint 10. It is discharged from the other end of the cylindrical body 4. In this example, since the diameter of the flexible cylindrical body 4 is approximately equal to the inner diameter of the tube 1, the flexible cylindrical body 4 is pressed in order from one end. When the diameter of the body 4 is much smaller than the inner diameter of the tube 1, the pressure of the pressure fluid is applied to the entire tube 1 at the same time.
The flexible cylindrical body 4 is pressed uniformly over its entire length. There is no particular problem with this, but in order to eliminate the fluid inside the flexible cylindrical body 4 more completely, it is best to press it in order from one end as described above. Preferably, the diameter of the flexible cylindrical body 4 is not excessively smaller than the inner diameter of the tube 1.

When all the fluid in the flexible cylindrical body 4 is discharged, the flattened flexible cylindrical body 4 is inserted into the tube 1, as shown in FIG. The string-like object 11 is connected to the flexible cylindrical body 4, and as shown in FIG. It can be done.

Note that when pulling out the flexible cylindrical body 4 from the tube 1, it is preferable to pull out the flexible cylindrical body 4 in a twisted state.

Next, in the second invention of the present application, a string-like elongated object is connected to the free end of the flexible cylindrical body 4 in the first invention, and the flexible cylindrical body 4 is turned over to form a pipe. At the same time, the string-like long object is inserted into the turned-over flexible cylindrical body 4, and the string-like long object and the flexible cylindrical body 4 are simultaneously pulled out from the tube 1. This is for pulling in the string-like object 11. Other implementation procedures can be carried out in exactly the same manner as in the first invention.

Function In the present invention, after the flexible cylindrical body 4 is turned over and inserted into the tube 1, the flexible cylindrical body 4 is crushed by fluid pressure, and the crushed flexible cylindrical body 4 is Since it is pulled out from the tube 1, the fluid in the flexible cylindrical body 4 is almost completely removed from the tube 1, and the contact area between the flexible cylindrical body 4 and the tube 1 is small. , the frictional resistance when pulling out the flexible cylindrical body is small.

Further, in the second invention, by crushing the flexible cylindrical body 4 with fluid pressure, the contact area between the flexible cylindrical body 4 and the string-like elongated object is increased, and the flexible cylindrical body 4 is compressed by fluid pressure. 4 and the string-like long object are integrated to form the pipe 1.
be extracted from.

Effects of the Invention According to the present invention, since the frictional resistance between the flexible cylindrical body 4 and the tube 1 is small, the force required for pulling it out is small, and the flexible cylindrical body 4 is not damaged or broken. There is nothing to do. Therefore, it becomes possible to use the flexible cylindrical body, which was conventionally disposable, several times. Further, by twisting the flexible cylindrical body 4 before pulling it out, the frictional resistance can be further reduced. In this case as well, since the fluid inside the flexible cylindrical body 4 is completely eliminated, it is easy to twist, and there is no fluid trapped in the middle, making it more effective. be.

Furthermore, in the second invention, the flexible cylindrical body 4
Since the and string-like long object are in close contact with each other, they move together, and the string-like long object passes through the flexible cylindrical body 4 as in the conventional method. The flexible cylindrical body 4 and the string-like long object can be pulled out as a unit while applying force to the string-like long object.

Furthermore, if the other ends of the tube 1 and the flexible cylindrical body 4 remain open when the pressure fluid is supplied from the pressure fluid inlet 9, the fluid in the flexible cylindrical body 4 may be excessively absorbed. The flexible cylindrical body 4 is not able to fully inflate after being discharged, and the pressure fluid sent in also escapes from the other end of the pipe 1, so no pressure is applied to the flexible cylindrical body 4. However, in the present invention, since the other end of the tube 1 is squeezed and the flexible cylindrical body 4 is also narrowed, the crushed flexible cylindrical body 4 Due to the movement of the fluid inside, the portion of the flexible cylindrical body 4 that has not yet been crushed expands sufficiently, and the tube 1 and the flexible cylindrical body 4 are
Sufficient pressure is also applied between the two ends, and the flexible cylindrical body 4 is sequentially crushed from one end, allowing the fluid inside to be completely discharged.

[Brief explanation of the drawing]

1 to 7 are longitudinal sectional views showing the process of implementing the present invention. DESCRIPTION OF SYMBOLS 1... Pipe, 2... Pressure vessel, 4... Flexible cylindrical body, 7... Folded part, 11... String-like object.

Claims (1)

[Scope of Claims] 1. One end of a flexible airtight cylindrical body is fixed in an annular shape, fluid pressure is applied to the rear part of the annular fixed part, and the flexible part is formed at the folded part formed there. While inverting the flexible cylindrical body so that the inside becomes the outside, the folded portion is advanced from one end of the tube to the other end, and the tube and the inverted flexible cylindrical body are respectively closed at one end of the tube. At the same time, at the other end of the tube, the end of the tube is squeezed to narrow the end of the inverted flexible cylindrical body, and pressure fluid is introduced between the tube and the flexible cylindrical body from one end of the tube. The flexible cylindrical body is compressed in its radial direction, and the fluid inside the flexible cylindrical body is discharged from the other end, and then the flexible cylindrical body is pulled out from the tube and the flexible cylindrical body is compressed in its radial direction. A method for inserting a string-like object into a tube, the method comprising drawing a string-like object coupled to a flexible cylindrical body into the tube. 2. A method for inserting a string-like object into a tube according to claim 1, which comprises pulling out the crushed flexible cylindrical body from the tube in a twisted state. 3 Fix one end of a flexible airtight cylindrical body in an annular shape, connect a string-like elongated object to the other end, and apply fluid pressure to the rear part of the annular fixed part of the flexible cylindrical body. The flexible cylindrical body is reversed so that the inside becomes the outside at the folded part formed there, and the folded part is advanced from one end of the tube to the other end, and the flexible cylindrical body is Turning the body over, passing the string-like elongated object into the turned-over flexible cylindrical body, closing the tube and the turned-over flexible cylindrical body at one end of the tube, and at the same time closing the tube at the other end of the tube. The end of the tube is squeezed to narrow the end of the inverted flexible cylindrical body, and pressure fluid is fed between the tube and the flexible cylindrical body from one end of the tube to make the tube flexible. The flexible cylindrical body is crushed in the radial direction to bring the flexible cylindrical body and the string-like elongated object inserted into the flexible cylindrical body into close contact, and the fluid inside the flexible cylindrical body is The flexible cylindrical body is discharged from the other end, and then the flexible cylindrical body is pulled out from the tube along with the string-like long object inserted into the flexible cylindrical body, and the string connected to the flexible cylindrical body is removed. A method for inserting a string-like object into a tube, which is characterized by drawing the string-like object into the tube.