JP2000055285A - Low-temperature fluid carrier equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constitute a carrier pipe without having any loop pipe or suppressing the number of loop pipes as less as possible by forming the carrier pipe of a low thermal expansion part composed of Fe-Ni based low thermal expansion coefficient alloy. SOLUTION: A pipe 1 carrying extremely low temperature liquefied gas is constituted of a low thermal expansion part formed of Fe-Ni based low thermal expansion coefficient alloy called invar alloy. The thermal expansion coefficient of the Fe-Ni based low thermal expansion coefficient alloy is approximately 1/10 compared with austenite based stainless steel used for a conventional pipe and the deformation of the carrier pipe formed of using the invar alloy caused by the expansion/contraction can be extremely minimized compared with the conventional pipe so that, when the both ends of the pipe 1 are fixed without providing any loop pipe, the thermal stress generated in the pipe 1 never exceeds the tolerable stress. This constitution can eliminate an overhang part in a part from one end 2 to the other end 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facility for transporting a low-temperature fluid such as LNG (liquefied natural gas) having a pipe for transporting the low-temperature fluid.

[0002]

2. Description of the Related Art Low-temperature fluid transport piping (hereinafter abbreviated as "low-temperature piping") in equipment for transporting low-temperature fluids such as LNG has conventionally been formed of austenitic stainless steel such as SUS304. It had been. Such stainless steel does not become brittle even at low temperatures, and is suitable as a material for low-temperature piping.

[0003] Here, since the stainless steel has a large coefficient of thermal expansion, the amount of expansion and contraction due to a temperature change in the pipe is large, and when the pipe is cooled to a low temperature by passing a low-temperature fluid, the pipe contracts. If the pipe does not have a mechanism for absorbing thermal contraction, the pipe will generate a thermal stress exceeding its allowable stress. Therefore, conventional low-temperature piping has loop pipes interposed in some places, and by providing a large number of such loop pipes, thermal shrinkage of the piping can be absorbed.

FIG. 3 is a diagram schematically showing a portion where a loop pipe of a conventional low-temperature pipe is arranged. A conventional low-temperature pipe 51 includes a loop pipe 52 shown in FIG.
It is arranged in one place. The pipe 51 is installed via a support 56 provided between adjacent loop pipes 52.

[0005]

However, the conventional SUS low-temperature pipe formed by providing a large number of loop pipes 52 has the following problems.

That is, the loop pipe 52 is formed by welding and connecting a large number of pipes at a large number of locations 54, 55, etc., and therefore, there is a problem that the number of pipes and welded locations increases. Further, in order to form the loop tube 52, an especially expensive elbow tube 53 is required. Also,
Cold insulation is provided along the outer circumference of the low-temperature piping,
The work of providing a cold insulator at the loop tube is difficult. Further, when a low-temperature fluid is transported by the low-temperature pipe, the flow direction of the fluid passing through the pipe is changed by the loop pipe, so that the pressure loss increases.

Further, since the portion of the loop pipe in the low-temperature pipe is overhanging, a space for laying the pipe is required by that amount, and especially when the pipe needs to be laid in a tunnel, the overhanging loop pipe is required. There is a problem that the diameter of the tunnel must be made large enough to allow the passage of the gas, which causes an increase in the cost of constructing the piping equipment.

Accordingly, an object of the present invention is to provide a facility for transporting a low-temperature fluid that has transport pipes that have no loop pipes or are formed with the number of loop pipes minimized.

[0009]

Means for Solving the Problems In order to solve the above problems, the low temperature fluid transportation equipment of the present invention has a transportation pipe comprising a low thermal expansion part formed of an Fe-Ni based low thermal expansion coefficient alloy. It is a feature (claim 1).

[0010] This makes it possible to minimize the number of loop pipes in the transport pipe. This is because transport pipes composed of low thermal expansion parts are significantly less deformed by low-temperature shrinkage when transporting low-temperature fluids, so a number of loop pipes are provided to absorb such deformation as in conventional SUS pipes. This is because, at least, the thermal stress acting on the pipe does not exceed the allowable stress.

Therefore, the number of loop pipes can be reduced as much as possible, and further, it is possible to eliminate the loop pipe at all, thereby reducing the number of welding points and the number of pipes. In addition, the work of providing the cold insulator becomes easy, and the space for laying the transportation pipe can be reduced. Further, when laying the equipment for transporting the low-temperature fluid in the tunnel, it is possible to eliminate the need to increase the diameter of the tunnel in relation to the loop pipe.

[0012] From these, it is possible to reduce the construction cost of the equipment.

[0013] Further, in the case where the first deformation restricting portion is provided at both ends of the low thermal expansion portion in the axial direction of the transporting pipe, the first deformation restricting portion being configured to suppress and move the deformation caused by the deformation due to the low-temperature shrinkage and to support it. 2), has the following significance. That is, the reaction force caused by suppressing the low-temperature shrinkage between the first deformation restricting portions is completely supported by the first deformation restricting portion, without affecting the non-low thermal expansion portion outside the first deformation restricting portion, As the non-low thermal expansion portion, a normal structure can be applied as it is.

A second deformation restricting section for fixing both ends of the low-thermal-expansion portion in the axial direction of the transportation pipe by moving the fixed-length portion at a predetermined distance while permitting the movement at a certain distance associated with the low-temperature shrinkage. (Claim 3), the thermal stress in the low thermal expansion portion is relaxed by the movement of the fixed distance during the low-temperature contraction, and the acting force on the second deformation restricting portion due to the low-temperature contraction can be reduced. . Thereby, the supporting strength of the second deformation limiting portion can be reduced, and the construction of the second deformation limiting portion can be simplified when constructing the equipment.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a side view of a part of a low-temperature fluid transport facility 10 according to an embodiment of the present invention, as viewed from the side of an axial direction of a transport pipe 1 provided in the facility. The low-temperature fluid transport facility 10 has a configuration in which first deformation restricting portions 4 and 5 are provided in a transport pipe 1. The transport pipe 1 is used for transporting a low-temperature fluid such as a low-temperature liquefied gas (LNG, LPG, etc.). One end 2 of the pipe 1 is connected to a low temperature liquefied gas storage tank 7 via a normal SUS pipe 6. Then, the low-temperature liquefied gas sent from the tank 7 is supplied to the pipe 1 from the end 2 of the pipe 1 through the pipe 6. The low-temperature liquefied gas sent from the other end 3 of the pipe 1 is supplied to each demand destination through a normal SUS pipe 8 connected to the end 3. The low temperature liquefied gas transported by the pipe 1 is extremely low temperature, and the inside of the pipe 1 has a temperature of about -160 ° C.
To a degree.

The pipe 1 is a low-thermal-expansion part formed of an Fe—Ni-based low-thermal-expansion coefficient alloy called an invar alloy. The Fe-Ni-based low coefficient of thermal expansion alloy forming such a low coefficient of thermal expansion contains 30 to 45% by weight of Ni and has a coefficient of thermal expansion of about 1.5 × 10 ⁻⁶ /.
° C. The coefficient of thermal expansion of such an Fe—Ni-based low thermal expansion alloy is about 1/10 of that of austenitic stainless steel such as SUS304 used for conventional piping. Therefore, when a transport pipe is formed using the Invar alloy, even when the low-temperature liquefied gas is transported, the deformation due to expansion and contraction can be significantly reduced as compared with the conventional SUS pipe, and the SUS pipe is formed. It is possible to minimize the number of loop pipes that had to be provided in the pipes as much as possible.
As shown in (2), even if both ends of the pipe 1 are fixed without providing a loop pipe, the thermal stress generated in the pipe 1 does not exceed the allowable stress.

As a result, the pipe 1 has one end 2
In the portion from the end 3 to the other end 3, the overhanging portion can be eliminated, and the space for laying the pipe 1 does not need to be large. Therefore, even if the pipe 1 shown in FIG. 1 is laid in a tunnel, it is not necessary to increase the diameter of the tunnel from the viewpoint of the space for laying the pipe 1, and the cost required for the laying is reduced. can do.

Further, since the number of loop pipes can be reduced, it is easy to provide a cooling material on the surface of the pipe 1.

The first and second end portions 2, 3 of the pipe 1 are provided with first deformation limiting portions 4, 5, respectively. The first deformation restricting portions 4 and 5 fix and support both ends 2 and 3 of the pipe 1. Thereby, axial movement accompanying deformation due to expansion and contraction of the pipe 1 is suppressed, and the pipe 1 is fixed. And the pipe 1 by the first deformation limiting parts 4 and 5
Is the fixing of both ends 2 and 3 of the pipe 1, and the pipe 1
Can be completely suppressed in the entire axial direction, and the effect of suppressing the low-temperature shrinkage of the pipe 1 is SU.
It does not reach the S-made pipes 6 and 8. Further, even if both ends of the pipe 1 are fixed by the first deformation restricting portions 4 and 5 in this manner, the thermal stress does not exceed the allowable stress of the pipe 1.

Further, the equipment 10 has support portions 26, 2 for supporting the pipe 1 as a structure and installing it on the ground or the like.
7, 28 are provided at various positions in the axial direction.

The support portion 26 is provided for fixing and supporting the pipe 1 in the axial direction against the influence on the pipe 1 due to an earthquake or the like. As a result, the pipe 1 is supported by the first deformation restricting portions 4 and 5 and the support portion 26 against an action such as an earthquake in the axial direction.

The support portion 27 is for supporting the own weight of the pipe 1 in the vertical direction (vertical direction in FIG. 1), and the support portion 28 is for supporting the pipe 1 in the horizontal direction (vertical to the paper surface in FIG. 1). Direction).

As described above, the pipe 1 can be shared and supported by the first deformation restricting portions 4 and 5 and the support portion 26 against the influence of the earthquake or the like acting on the pipe 1, so that the pipe 1 can be stably provided.
Can be supported.

The supporting portions 26, 27 and 28 are provided at various points in the axial direction of the pipe 1 as required for the installation of the pipe 1 in addition to those shown in FIG. In providing these support portions, since the pipe 1 is not provided with a loop tube, the support portions can be provided at arbitrary positions. That is, in the case of a conventional SUS pipe, it was necessary to arrange a large number of loop pipes. Therefore, the position of the support portion for supporting the pipe and installing it on the ground or the like was determined according to the position of the large number of loop pipes. However, when providing the support portion, the support portion can be provided at an arbitrary position without being restricted by the position of the loop tube. Thereby, the equipment 10
Construction is easy.

Next, a low-temperature fluid transport facility 20 according to another embodiment will be described with reference to FIG. FIG.
Shows a side view of a part of the facility 20 as viewed from the side in the axial direction of the transport pipe 11 provided in the facility 20.

The equipment 20 for transporting low-temperature fluid is provided with a second deformation restricting part 14, 1 in the transport pipe 11 comprising the low thermal expansion part.
5 is provided. The second deformation restricting portions 14 and 15 are respectively provided at both ends 12 and 13 of the transportation pipe 11.

The second deformation restricting portions 14 and 15 are connected to the pipe 1
In order to allow the deformation in the axial direction due to the expansion and contraction of 1 in a certain range, it is possible to move in the axial direction within a certain upper limit in accordance with the deformation. This causes the pipe 11 to expand and
When the deformation due to shrinkage is to occur, the movement of both ends 12, 13 accompanying the deformation is allowed, so that the acting force on the second deformation restricting portions 14, 15 from the pipe 11 is reduced. .

Thus, the second deformation restricting unit 1 of the equipment 20
Regarding 4 and 15, the supporting strength can be reduced, and the supporting structure of the second deformation limiting portion can be simplified.

When the second deformation restricting portions 14 and 15 move by a certain distance in accordance with the deformation of the pipe 11, the ends 12 and 13 of the pipe 11 are fixed, so that the transport pipe can be stably supported. .

If there is little room to absorb the movement of the two ends 12, 13 of the pipe 11 by the pipes 6, 8, as shown in FIG. 2, a SUS having a loop pipe, an elbow pipe or the like (not shown) is used. Piping parts 17 and 18 at both ends 1
2 and 13 may be provided outside to absorb the movement of both ends 12 and 13 of the pipe 11.

The pipe 11 is provided with the support portions 26 and the like (not shown) at various positions in the axial direction.

Although FIGS. 1 and 2 show an example in which a loop pipe is not provided at all as a transport pipe, a loop pipe may be provided.
As described above, when the transport pipe is configured to have a low thermal expansion portion, the contraction and expansion are extremely small.
Therefore, even if a loop pipe is provided, the expansion and contraction can be absorbed by using a very small number of loop pipes and using a loop pipe having a small loop size, and the space for laying the transport pipe can be reduced. This is because it is possible to reduce the number of times.

Further, in order to cope with the situation of the pipe line, a curved pipe or an elbow may be included in the middle of the transport pipe.

[0035]

As described above, since the equipment for transporting low-temperature fluid of the present invention is provided with the transportation pipe comprising the low thermal expansion part, the construction of the equipment is easy and the cost is reduced. It has the effect of being able to do so.

Further, even if both ends of the transport pipe are fixed by the deformation restricting portions, the effect that the thermal stress generated in the transport pipe does not exceed the allowable stress of the pipe is exerted.

[Brief description of the drawings]

FIG. 1 is a side view of a low-temperature fluid transport facility provided with a first deformation restricting unit.

FIG. 2 is a side view of a low-temperature fluid transport facility provided with a second deformation restricting unit.

FIG. 3 is a diagram illustrating a conventional pipe for transporting low-temperature fluid.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transport pipe 2, 3 End of transport pipe 4, 5 First deformation limiting part 6 Pipe 7 Storage tank 8 Pipe 10 Facility for low-temperature fluid transport 11 Transport pipe 12, 13 End of transport pipe 14, 15 Second deformation restricting part 17, 18 SUS pipe part 20 Low temperature fluid transportation equipment 26, 27, 28 Support part 51 Low temperature pipe 52 Loop pipe 53 Elbow pipe 54, 55 Pipe connection point 56 Support part

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Naoshige Kubo 4-1-2, Hiranocho, Chuo-ku, Osaka-shi, Osaka Inside Osaka Gas Co., Ltd. (72) Inventor Taku Iwahashi 4 Hiranocho, Chuo-ku, Osaka-shi, Osaka 1-2 1-2 Osaka Gas Co., Ltd. (72) Shuji Yamamoto 5-11-11 Nishijima, Konohana-ku, Osaka City, Osaka Prefecture Osaka Gas Co., Ltd. Production Technology Center (72) Inventor Kazuhiro Ogawa Central, Osaka City, Osaka Prefecture 4-5-33 Kitahama-ku, Sumitomo Metal Industries, Ltd. (72) Inventor Masao Akiyama 4-5-33 Kitahama, Chuo-ku, Osaka-shi, Osaka Sumitomo Metal Industries, Ltd. (72) Inventor Hiroaki Masatomo Wakayama, Wakayama 1850, Minato-shi, Sumitomo Metal Industries, Ltd.Wakayama Works (72) Inventor, Kanji Komori 8, Harima-cho, Harima-cho, Kako-gun, Hyogo Kawasaki Heavy Industries, Ltd. Harima Plant (72) Inventor Soji Kishimoto 8 Harima-cho Niijima, Kako-gun, Hyogo Prefecture Kawasaki Heavy Industries, Ltd. Harima Factory

Claims (3)

[Claims] 1. A low-temperature fluid transport facility comprising a transport pipe comprising a low thermal expansion portion formed of an Fe—Ni-based low thermal expansion coefficient alloy. 2. A first deformation restricting portion which is provided at both ends of a low thermal expansion portion in the axial direction of the transport pipe so as to restrain and support movement due to deformation due to expansion and contraction. The facility for transporting cryogenic fluid according to claim 1. 3. When both ends of the low-thermal-expansion portion in the axial direction of the transportation pipe are moved by a certain distance while allowing the ends to move by a certain distance due to deformation due to expansion and contraction, the both ends are moved. The low-temperature fluid transport facility according to claim 1, further comprising a second deformation restricting portion for fixing the fluid.