JPS6218795Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to the invention of a pipe end connection mechanism for the insertion method, which forms a stable connection structure that is preferable in terms of strength when forming a pipe according to the insertion method. The aim is to obtain an inexpensive mechanism.

In cases where the pipe body has aged or corroded over time after installation, it is common practice to dig out and remove the entire old pipe body and replace it by laying and burying the new pipe body. When using a general method such as It cannot be carried out if there are various structures on the line, and even if there are no special structures, it is normal that the line is at least used for paving or growing plants, so those pavement works must be redone. Alternatively, since it is necessary to perform a considerable amount of work to replant plants, etc., the number of man-hours includes work that requires special techniques in addition to simple excavation.
It has to become complicated. As a method to avoid such disadvantages, the present inventor proposes the adoption of the insertion method, as shown in Figure 1, which requires rehabilitation of the existing pipe 20. A pit 21 is formed before and after the range α, a new inner pipe 22 is inserted into the old pipe 20a between these pits 21 and 21, and the inner pipe 22 is connected to the existing pipe 20 that does not require rehabilitation. However, when such an insertion method is used, the pipe to be rehabilitated remains buried, so generally when constructing the area α that requires rehabilitation, which is several tens of meters or more, the pit 21 is simply excavated. The above-mentioned disadvantages of the general law can be fully overcome. However, in implementing this type of insertion method, there is no preferable pipe end connection mechanism between the internally installed pipe and the existing pipe that does not require rehabilitation. There is a disadvantage that it is difficult to implement the construction method concretely. That is, to further explain the circumstances during this period, as mentioned above, the old pipe 20a and the existing pipe 2 that require rehabilitation
In most cases, cast iron pipes have been used since the time when the pipes were laid.On the other hand, the pipes 22 to be installed have the above-mentioned rehabilitation required range α of 100 m.
In addition, it is preferable to use a synthetic resin pipe such as a polyethylene pipe in order to prevent misalignment, bent pipes, or corrosion in the section. However, for this connection purpose, some secondary
As shown in the figure, a spacer 12 is interposed between the inner pipe 22 fitted with a hot wire saddle 19 as appropriate and the end of the old pipe 20a, a different diameter coupling ring 11 is used, and the excavation length when inserting Since a length of 4 to 8 m is required, covering this length with only a joint would require an extremely long joint. Therefore, a long joint is used to connect the cast iron pipe 23 with the same diameter as the inner pipe 22 to the end of the inner pipe 22. 15, and then the cast iron pipe 23 and the existing pipe 20 are further connected by another joint ring 17 of different diameter, but such a structure is often used. It is complicated and requires packing materials 14, 16, 16 and 18, 18 at each joint.
In addition, many members including the push rings 13, 13a, and 13b are required, and it is obvious that the use of such a large number of members is inferior in strength and disadvantageous in terms of cost. In addition, since it is designed to slide due to expansion and contraction due to heat, etc., there is a strong tendency for leaks to occur from the sliding portion. For example, if the length of the inserted polyethylene pipe 22 is 100 m and a temperature difference of ±15°C occurs, the coefficient of linear expansion is 1.4 × 10 ^-4 for polyethylene.
cm/cm℃, and for cast iron it is 1.1×10 ^-5 cm/cm℃, so the polyethylene pipe 22 is ±
This results in a large expansion and contraction of 193.5 mm, and there are drawbacks such as the inability to appropriately cope with such large expansion and contraction.

The present invention was devised through research to eliminate the disadvantages of the conventional ones as described above, and its specific embodiment is as shown in FIG. 3 and subsequent figures. That is, between the old pipe 20a and the inner pipe 22 as described above, a stiffener 7 is installed inside the inner pipe 22 corresponding to the end of the old pipe 20a, and tightening rings 25, 25 as shown in FIG.
A tightening member 27 is provided with inner and outer packings 26, 26 which are flexible and bulge in the middle part.
An elastic material bulging sealing means 8 is interposed to seal between the old pipe 20a and the inner pipe 22 by tightening the packings 26 and 26 to respectively bulge the packings 26 and 26. As shown in Fig. 5, there are a stiffener 31 and packing 32, 32 for connecting a polyethylene pipe and a metal pipe such as a steel pipe.
and a fiber-filled resin jacket 33 using a joint body 1 such as a transition joint. That is, the joint body 1 shown in FIG. 3 is adapted to the construction conditions at each construction site, and in order to adopt a factory-produced joint body 1 of predetermined dimensions, an auxiliary resin pipe 3 and a metal pipe are used. Using 3a,
These two pipes 3, 3a are butt fused 6 and welded 6a.
The above-mentioned joint body 1 is used to connect the polyethylene pipe 22 and the inner steel pipe 4, and between these two pipes 3, 3a, but in principle, the joint body 1 is made of resin. It is natural that the inner pipe (polyethylene) 22 and the inner steel pipe 4 as described above can be directly connected since it is characterized by effectively connecting a pipe and a metal pipe.
Furthermore, a protective pipe 2, such as a so-called long assembly, is covered on the outer periphery of the inner steel pipe 4 from the inner pipe 22 connected in this way, and is connected to the existing pipe 20 or the existing pipe 20 as appropriate. An elastic material bulging sealing means 8 shown in FIG. 6 similar to that described above is also interposed between the inner surface of the short armored pipe 5 of the same diameter and the steel pipe 4,
Therefore, a sealing mechanism using push rings 35 is installed between both ends of the protective tube 2 and the outer surface of the old tube 20a and the outer surface of the short exterior tube 5 (or the existing tube 20), as shown in an example in FIG. Form. That is, a suitable step 36 is formed on the inner surface of the flange side of the above-mentioned protective tube 2, a back-up spring 37 and packing materials 38, 39 are inserted, and these packing materials 38, 39 are tightened with a press ring 35. A pull-out prevention ring 40 is attached to the end of the short exterior pipe 5 or the existing pipe 20 by welding or other means as necessary.

In addition, an injection port 10 is formed in the middle of the protective tube 2 as described above, and after the various parts have been connected and tightened as described above, an appropriate filler is injected to maintain airtightness even when the tube body contracts. It has an integral connection structure that maintains its properties.

That is, to explain the general construction procedure of the above-mentioned device according to the present invention, the required length range is measured at the boundary between the old pipe 20a to be rehabilitated and the existing pipe 20 in the manner shown in FIG. After excavating and cutting the inner pipe 22, such as a polyethylene pipe, the inner pipe 22 is inserted into the old pipe 20a, and its end is inserted into the old pipe 20a as shown on the left side of FIG.
The sealing means 8 as described above is used to seal between the old pipe 20a and the inner pipe 22 while protruding from the end of the inner pipe 22, and then the protective pipe 2 is temporarily attached to the old pipe 2.
0a, the protective tube 2 is further left to the left from the state shown in Fig. 3.
In this state, if the length of the excavated part described above is increased or if a factory-produced joint body 1 of a predetermined size is used, the resin pipe 3 is covered. The inner steel pipe 4 and the outer short pipe 5 are charged into the joint body 1 having the metal pipe 3a and the inner steel pipe 3a, and then the ends of the resin pipe 3 and the inner pipe 22 are butt fused, and the inner steel pipe 4 is
and the metal 3a, and another elastic material bulging sealing means 8 shown in the center of FIG. 3 is interposed, and these sealing means 8 are tightened together. After doing this, the protective tube 2 that had been slid onto the old tube 20a as described above was pulled out and set on the area centered on the joint body 1 as shown in FIG. 3, as shown in FIG. 4. A pushing ring 35 such as the one shown in FIG. The entire process ends when it is closed.

According to the present invention as described above, a connecting structure is formed substantially with the joint body 1 as the main body, and the old pipe 20
a and the existing pipe 20, and yet the joint mechanism can be greatly simplified; and since an elastic material expansion sealing means is used between the inner pipe and the old pipe, and between the inner metal pipe and the existing pipe or the outer short pipe, these pipes are automatically centered and set; in particular, since the middle parts of the elastic materials arranged inside and outside as the elastic material expansion sealing means are compressed between the tightening rings to expand, these tightening seals are very simple and provide a favorable seal, simplifying the handling of the work and, in combination with the filler material 9 filled between the sealing means, a mechanism with favorable strength can be obtained; and since expansion and contraction due to temperature differences and the like are appropriately tolerated by the sealing means 8 and the filler material 9, and since the sealing structure extends over a reasonable length range, favorable airtightness can be ensured. This is a device with great practical effects.

[Brief explanation of drawings]

The drawings show the technical content of the present invention; Figure 1 is an explanatory diagram showing an overview of the insertion method to which the present invention is applied, and Figure 2 is a cross-section showing the connection mechanism of the conventional method. 3 is a sectional view similar to FIG. 2 of the device according to the present invention, FIG. 4 is a sectional view of the sealing mechanism using the press ring, FIG. 5 is an explanatory view of the joint body, and FIG. The figure is an explanatory view of the elastic material bulging sealing means. However, in these drawings, 1 is a joint body,
2 is the protective tube, 4 is the inner metal tube, 5 is the outer short tube, 7
and 31 is a stiffener, 8 is an elastic material expansion sealing means, 9 is a filling material, 10 is an injection port, 20 is an existing pipe, 20a is an old pipe to be rehabilitated, 22 is an inner pipe such as a polyethylene pipe, and 25 is a tightening member. ring, 26 and 3
2, 38, and 39 are packing materials, 27 is a tightening member, 33 is a resin sleeve, 35 is a press ring, and 37 is a back-up spring.

Claims (1)

[Scope of utility model registration request] In the connection section using the insertion method, which inserts an inner pipe made of a synthetic resin pipe such as a polyethylene synthetic resin pipe into an old pipe that requires rehabilitation, and connects the inner pipe to an existing pipe that does not require rehabilitation, the inner pipe The inner metal pipe inserted into the existing pipe or the outer short pipe connected to the existing pipe is connected via a joint body, and the inner metal pipe and the existing pipe are connected between the inner pipe and the old pipe and the inner metal pipe and the existing pipe. Alternatively, an elastic material bulging seal means is provided between the outer short pipe and the outer short pipe for sealing, and the intermediate portions of the elastic members disposed inside and outside are compressed between the tightening rings to bulge, and further the old pipe is A protective pipe is covered and sealed between the end and the existing pipe or the exterior short pipe, and between the old pipe and the inner pipe between the protective pipe and the inner pipe and the inner metal pipe, and the existing pipe. Alternatively, a pipe end connection mechanism in an insertion construction method, characterized in that a filler is injected and filled between each elastic bulging seal material provided between an exterior short pipe connected to an existing pipe.