JP2517579Y2 - Adiabatic tube - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe which is buried or exposed on the ground and which requires heat insulation.

[0002]

2. Description of the Related Art When hot water or cold water passes through a pipe,
It is often necessary to retain the thermal energy that it possesses as much as possible. Alternatively, there is a case where it is necessary to prevent freezing and rupture due to a rapid temperature change of the outside air, and the outer circumference of the pipe is covered with a heat insulating material to meet this need. In recent years, in response to this demand, a method in which a heat insulating material is wound around the outer circumference of a steel pipe in a factory in advance, and a fixed length single pipe covered with a steel pipe as a casing is connected to the outside in the ground or above the ground to form a pipeline Is also being developed.

[0003]

[Problems to be solved by the invention] If it is manufactured as a double pipe in a factory in advance, it is possible to avoid complicated construction such as winding of a heat insulating material on site, which is a great advantage. However, it is unavoidable to connect the single pipes brought to the site. 3 and 4 are a longitudinal sectional front view and a cross-sectional view taken along line AA of the heat insulating pipe of the related art, showing an inner pipe 11a.
A heat insulating material 12a is wound around the outer circumference of the
Is externally fitted and the outer circumference of the outer tube is painted to prevent corrosion. According to the manufacturer's explanation, the procedure for connecting this single pipe at the site is as shown in FIGS.
First, the inner pipes 11a are welded to each other, the joint insulating heat-insulating material 101 is covered on this connection portion, the band 102 is tightened, the steel joint collar 103 is covered on the outer surface thereof, and the end surface thereof is locally welded. 104 is applied to the outer surface of the collar to complete the process.

The problem is that such connection work cannot be said to be highly efficient. Since fluid is pumped into the inner pipe, X-ray inspection is indispensable after welding, and 1 joint construction including this will require considerable time and labor. Further, the steel pipe is a material that easily rusts, and the inner anticorrosion coating is burned out by welding heat, which raises doubts about the service life. When welding the outer pipe, there is a risk of deterioration of the heat insulating material that faces the heat, and in addition to these quality issues, the time required for on-site construction is
The experience that it is about 10 times that of ordinary non-insulated pipe connection is left, which is a big problem in practical use.

In order to solve the above-mentioned problems, the present invention aims to provide a heat insulating pipe in which single pipes can be easily connected to each other.

[0006]

The heat insulating pipe according to the present invention is
A ductile cast iron pipe having a receiving port of length P ₁ and a straight tubular insertion port as an inner pipe, and having an inner diameter larger than the maximum outer diameter of the inner pipe and a length P ₂ smaller than P ₁ A ductile cast iron pipe having a straight tubular insertion opening and having a total length excluding the length P ₂ which is slightly larger than the total length of the inner pipe excluding the length P ₁ as the outer pipe. The innermost and outermost cut surfaces of the mouth are almost aligned and overlapped, and a large number of composite pipes are formed by filling the hollow space between them with a heat insulating material, and the insertion ports of the inner and outer pipes of the preceding composite pipe are respectively formed. The above-described problem is solved by being able to fit into the receiving port of the following composite pipe facing each other, and the outer end face of the receiving port of the outer pipe and the push ring can be joined together by water sealing.

[0007]

[Function] The inner and outer end faces of the inner and outer pipes of the preceding composite pipe are staggered, the hollow part in the middle where both pipes overlap is filled with a heat insulating material, and the end face of the inner pipe is exposed over a certain range. Forming a spigot. Since there is a slight difference in the total length of the inner tube and the outer tube excluding the receiving port, the length of the exposed insertion port is slightly smaller than the receiving port length P ₁ . And the socket length P of the outer tube
_{Since 2} is set smaller than the inlet length P ₁ of the inner pipe,
When the inner pipe insertion port of the preceding composite pipe is fitted into the inner pipe receiving port of the subsequent composite pipe via a water sealing means such as a rubber ring and the subsequent pipe is moved, distortion or twisting of the rubber ring etc. may occur. It is possible to proceed with fitting completely while checking and correcting. Eventually, the insertion of the outer pipe and the insertion of the receiving port will start at the same time, and when both parts of the outer pipe are butted against each other, there will be a sufficient water-sealing action between the inserting port and the receiving port of the inner tube and the heat of the conduit. Some gap is left to absorb the expansion due to.

On the other hand, the direct joining of the composite pipes and the composite pipes is a so-called mechanical joining using a water ring means such as a rubber ring using a push ring, and therefore, it is as easy as a normal single pipe connection. It can be installed in. Looking at each individual pipe of the composite pipe, different end faces are formed on the receiving side and the inserting side of the inner pipe and the outer pipe, but if you connect multiple of these, any cross section of the pipe line All are protected by heat insulating material, and since there is no break, the heat insulating effect is fully exerted.

[0009]

1 is a longitudinal sectional front view showing an embodiment of the present invention. Both the preceding composite pipe 1A and the following composite pipe 1B are formed by inner pipes 11A and 11B, heat insulating materials 12A and 12B, and outer pipes 13A and 13B, respectively. One end of the inner tube is a receiving port 14 having a length P ₁ , the other end is an insertion port 15, and one end of the outer tube is a receiving port 16 having a length P ₂ (where P ₁ > P ₂ ) and the other. The end consists of the insertion slot 17. When compared with each other except for the receiving portion, all of the inner tube 11 has a slightly smaller total length than the outer tube 13, so that the leading outer tube insertion opening 17A and the trailing outer tube receiving opening 16B are butted. At this time, a gap C approximately equal to the difference in the total length is formed between the preceding inner pipe insertion port 15A and the subsequent inner pipe receiving port 14B, so that the expansion due to the heat of the conduit can be absorbed.

In this embodiment, since the inner tubes are joined to each other by a so-called push-on type receiving port and inserting port, it is sufficient to apply an outer tube having a relatively small inner diameter without a flange on the outer diameter of the receiving port. It is possible to secure a layer thickness of a heat insulating material, which is thermo-economically advantageous.

The procedure for joining the composite pipes as shown in FIG. 1 is as simple as the ordinary joining of the single pipes. Figure 2 (a)
(E) are sectional front views showing this procedure. That is, (a) the rubber ring 21 is attached to the receptacle 14B of the inner tube of the subsequent composite tube 1B. (B) The push ring 3 and the rubber ring 22 are deposited in the insertion opening 17A of the outer tube of the preceding composite tube 1A. (C) The receiving end 14B of the subsequent inner pipe is inserted until the tip of the insertion port 15A of the preceding inner pipe passes through the rubber ring 21. As for the insertion force at this time, the insertion force of only the inner tube should be considered. (D) Insert the thin plate gauge G into the insertion portion of the inner pipe through the gap between the front and rear end faces of the composite pipe, and confirm that the rubber ring 21 is correctly attached at a predetermined position. (E) Further, when the inner and outer pipes are inserted into each other and the receiving ports are fitted to each other so that the outer pipe inserting ports 17A and 16B come into contact with each other, the rubber ring 22 deposited in the outer pipe inserting port 17A. Is set in the receiving port 16B and is fastened with a bolt 31 and a nut 32 via the push ring 3 to completely seal the same.

[0012]

As described above, according to the present invention, since a known means using a joint is sufficient for joining the composite pipes,
The work load is low and the efficiency is good. Moreover, the joint between the inner tubes can be first checked to check whether the water-sealing means is properly provided, or correction can be made. Since the inner and outer pipes are joined by a combination of the fitting type of the receiving port and the insertion port, even if the cutting pipe is cut according to the actual length at the joining site, it can be easily dealt with and it is easy to provide flexibility. Even if the pipe expands and contracts due to heat transfer from the fluid in the conduit, a slight gap is provided between the receiving end and the inserting end of the inner pipe. In addition, since the inner pipe is a push-on type joint and the outer pipe is a mechanical type joint, a sufficient layer thickness of the heat insulating material can be secured to cut off heat transfer seamlessly, and the insertion force at the time of joining is relatively small. That is excellent. Further, in order to take earthquake into consideration, if SII type, S type, etc., which are specified in JIS as the type of outer pipe joint, are applied, it is possible to form a pipeline for a heat insulating pipe by a seismic joint.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing an embodiment of the present invention.

FIG. 2 is a vertical sectional front view showing a joining procedure of the embodiment according to (a) to (e).

FIG. 3 is a vertical sectional front view showing a conventional technique.

4 is a sectional view taken along the line AA of the conventional technique shown in FIG.

FIG. 5 is a perspective view for explaining the above-described joining procedure of the prior art with (a) to (e).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Composite pipe 3 Push ring 11 Inner pipe 12 Insulation material 13 Outer pipe 14 Inner pipe receiving port 15 Inner pipe inserting port 16 Outer pipe receiving port 17 Outer pipe inserting port 21 Rubber ring 22 Rubber ring 31 Bolt 32 Nut C Gap G Thin plate gauge

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiki Okamoto 1-12-19 Kitahorie, Nishi-ku, Osaka City Kurimoto Iron Works Co., Ltd. (56) References: 58-106495 (JP, U) 62-204095 (JP, U) Actually open 4-44583 (JP, U) Actually open 58-144173 (JP, U)

Claims (1)

(57) [Scope of utility model registration request] _1. A ductile cast iron pipe having a receiving port of length P ₁ and a straight tubular insertion port as an inner pipe, having an inner diameter larger than the maximum outer diameter of the inner pipe and having a length smaller than P _1. A ductile cast iron pipe having a receiving port P ₂ and a straight tubular insertion port and having a total length excluding the length P ₂ slightly larger than the total length of the inner pipe excluding the length P ₁ is used as the outer pipe and is outside the inner pipe receiving port. The end face and the innermost cut surface of the outer pipe receptacle are almost aligned and overlapped, and the hollow space between them is filled with a heat insulating material to form a large number of combined pipes. The heat-insulating pipes are characterized in that the respective insertion ports of the outer pipes are fitted into the respective receiving ports of the following composite pipes, and the outer end face of the receiving port of the outer pipe and the push ring can be water-sealed together.