JP2020164234A - Thermally insulating construction method - Google Patents

Abstract

To provide a thermally insulating construction method that is superior in performance such as thermally insulating performance although site construction can be performed with excellent workability, according to the present invention.SOLUTION: A press plate 20 is installed so that an injection space S is formed with an outer peripheral surface 10A of a cylindrical tank 10 apart from the outer peripheral surface 10A, and a foam undiluted solution is injected into the injection space S while the cylindrical tank 10 is rotated, and foamed to form a heat insulating foam layer on the outer peripheral surface 10A of the cylindrical tank 10.SELECTED DRAWING: Figure 2

Description

The present invention relates to a heat-insulating construction method in which a heat-insulating structure including a heat insulating layer is constructed on the outer peripheral surface of a cylindrical tank.

Conventionally, a cylindrical tank has been used as a tank for storing low-temperature liquids such as liquefied natural gas (LNG), liquefied ethylene gas (LEG), and liquefied petroleum gas (LPG). It is known that a cylindrical tank has a heat-insulating structure by providing a heat insulating layer or the like on the outer peripheral surface in order to prevent the low-temperature liquid stored inside from being heated by external heat (for example, a patent). Refer to Documents 1 and 2). The heat insulating layer is generally composed of a foam such as urethane foam. In addition, a face material for reinforcement is often provided on the surface of the heat insulating layer.

Cylindrical tanks have been miniaturized in recent years, and it may be required to construct a heat shield structure on site. Therefore, a heat insulating layer may be formed by spraying on-site or by attaching a pre-foamed foam molded product to the outer peripheral surface with an adhesive. Further, after forming the heat insulating layer, the face material is further attached to the outside of the heat insulating layer by an adhesive or the like.

Japanese Unexamined Patent Publication No. 2016-16806 JP-A-2018-119634

However, when the heat insulating layer is formed by spraying on-site, it is difficult to control the thickness to be constant, and the heat insulating performance may be inferior. In addition, since the construction of the heat insulating layer and the construction of the face material are separate processes, there is room for improvement in terms of workability. On the other hand, when the heat insulating layer is formed by pasting a molded product, there is room for improvement such as followability of the heat insulating layer to the tank curvature, deterioration of heat insulating property due to split sticking, and an increase in the number of manufacturing steps.

Therefore, it is an object of the present invention to provide a heat-insulating construction method having excellent performance such as heat insulation performance while being able to perform on-site construction with good workability.

The gist of the present invention is the following [1] to [10].
[1] A holding plate is installed so as to form an injection space between the outer peripheral surface and the outer peripheral surface of the cylindrical tank.
A heat-insulating construction method in which a heat-insulating foam layer is formed on the outer peripheral surface of a cylindrical tank by injecting the foam stock solution into the injection space while rotating the cylindrical tank and foaming the foam stock solution.
[2] A face material is supplied along the inner surface of the presser plate facing the outer peripheral surface, and the foam stock solution is injected into the injection space while supplying the face material to the surface of the heat insulating foam layer. The heat-insulating construction method according to the above [1], which integrates the face materials.
[3] The heat-insulating construction method according to the above [2], wherein the face material is a glass cloth, a glass mesh, a metal plate or a plastic sheet.
[4] The heat-insulating construction method according to any one of the above [1] to [3], wherein the heat insulating foam layer is formed in a plurality of rows along the axial direction of the cylindrical tank.
[5] The heat-insulating construction method according to any one of [1] to [4] above, wherein the heat insulating foam layer is formed a plurality of times in the thickness direction.
[6] The heat insulating foam layer is formed in a plurality of rows along the axial direction of the cylindrical tank, and the heat insulating foam is formed so that the joints between the rows of the inner layer and the joints between the rows of the outer layer are displaced. The heat-insulating construction method according to the above [5], which is performed a plurality of times in the thickness direction.
[7] The heat insulating construction method according to any one of [1] to [6] above, wherein a release sheet is supplied along the inner surface of the holding plate facing the outer peripheral surface.
[8] The heat insulating construction method according to any one of the above [1] to [7], wherein the liquid leakage prevention member is arranged on both sides of the injection space and at least one lower portion.
[9] The heat-proof construction method according to the above [8], wherein the liquid leakage prevention member is any of a foam molded product, a tube, and a release sheet.
[10] The heat insulating construction according to any one of [1] to [9] above, wherein the guide roller is brought into contact with the outer peripheral surface and the holding plate is arranged at a constant distance from the outer peripheral surface. Method.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a heat-insulating construction method having excellent performance such as heat insulation performance while being able to perform on-site construction with good workability.

It is sectional drawing of the cylindrical tank which has a heat-shielding structure formed in the construction method of 1st Embodiment. It is a schematic side view for demonstrating the construction method of 1st Embodiment. It is a schematic perspective view for demonstrating the construction method of 1st Embodiment. It is a schematic side view for demonstrating the construction method of 1st Embodiment. It is a schematic side view for demonstrating the modification of the construction method of 1st Embodiment. It is a vertical sectional view of the cylindrical tank which has a heat-shielding structure formed by the construction method of 2nd Embodiment. It is sectional drawing of the cylindrical tank which has the heat-shielding structure formed by the construction method of 2nd Embodiment.

[First Embodiment]
FIG. 1 shows a heat insulating structure 11 constructed on a cylindrical tank 10 by the construction method of the first embodiment of the present invention. The cylindrical tank 10 stores a liquid inside and has a cylindrical side wall. The cylindrical tank 10 is a tank for storing low-temperature liquids such as LNG, LEG, and LPG. The heat-insulating structure 11 constructed on the cylindrical tank 10 includes a heat insulating foam layer 12 and a face material 13. The heat insulating foam layer 12 is formed on the outer peripheral surface 10A of the side wall of the cylindrical tank 10, and the face material 13 is further attached to the outer peripheral surface of the heat insulating foam layer 12.

The heat insulating foam layer 12 may be any material that can be used as a heat insulating material, such as urethane foam, phenol foam, and styrene foam, but urethane foam and phenol foam are preferable from the viewpoint of ease of manufacture and curing speed, and urethane foam is preferable. More preferred. By using urethane foam, self-adhesiveness, foamability, heat insulation, etc. tend to be good. The thickness of the heat insulating foam layer 12 is not particularly limited, but is, for example, 20 to 150 mm, preferably 50 to 100 mm.
Examples of the face material 13 include a cloth material such as glass cloth, a mesh material such as glass mesh, a metal plate such as an iron plate and a steel plate, and a plastic sheet. The thickness of the face material 13 is not particularly limited, but is, for example, 0.1 to 5 mm, preferably 0.15 to 1 mm.

Next, the construction method of the heat-insulating structure will be described in detail with reference to FIGS. 2 to 4.
In this construction method, as shown in FIGS. 2 and 3, the heat shield structure 11 is constructed by using the pressing plate 20 and the foam stock solution supply device 21 and the like. The foam stock solution supply device 21 is a device for supplying the foam stock solution, and includes a discharge port 22 for discharging the foam stock solution. The foam stock solution supply device 21 can move the discharge port 22 in the horizontal direction (that is, the axial direction X of the cylindrical tank 10 described later).

The foam stock solution supplied from the foam stock solution supply device 21 is a liquid for forming a heat insulating foam layer, and becomes a foam (heat insulating foam layer 12) by being foamed and cured. For example, in urethane foam, the foam stock solution contains a polyisocyanate component, a polyol component, a foaming agent, a foam stabilizer, a catalyst and the like. Such a foam stock solution is prepared, for example, by mixing a polyisocyanate component (two liquids) with one liquid in which a foaming agent, a foam stabilizer, a catalyst, etc. are mixed with a polyol component in the foam stock solution supply device 21. Will be done.

As shown in FIG. 2, the cylindrical tank 10 is placed on the turning roll 30 so that its axial direction X is horizontal. The turning roll 30 is provided with, for example, two sets of two rolls arranged along the axial direction X of the cylindrical tank 10 (that is, the vertical direction of the paper surface in FIG. 2), and the cylindrical tank is placed on the four rolls. 10 is placed. The axial direction of each roll of the turning roll 30 coincides with the axial direction X of the cylindrical tank 10, and by rotating each roll in the same direction, the cylindrical tank 10 can be rotated about the axis. The axial length of each roll constituting the turning roll 30 is sufficiently shorter than the axial length of the tank 10.
Of course, the number of rolls of the turning roll 30 is not particularly limited, and may be 6 or the like. Further, the cylindrical tank 10 may be rotated by any means other than the turning roll 30 as long as the cylindrical tank 10 can be rotated about the axis.

The holding plate 20 is supported by, for example, a base 25 and is installed so as to be separated from the outer peripheral surface 10A of the cylindrical tank 10, thereby forming an injection space S between the holding plate 20 and the outer peripheral surface 10A. The injection space S is a space for injecting the foam stock solution. A discharge port 22 is arranged above the injection space S.
Here, the inner surface 20A of the pressing plate 20 facing the outer peripheral surface 10A is formed on a curved surface along the outer peripheral surface 10A. As a result, the distance between the outer peripheral surface 10A of the cylindrical tank 10 and the inner surface 20A of the holding plate 20 can be made constant along the circumferential direction of the cylindrical tank 10.

As shown in FIG. 2, the base 25 is provided with a guide roller 28. The guide roller 28 is arranged so as to abut on the outer peripheral surface 10A of the cylindrical tank 10. When the guide roller 28 comes into contact with the outer peripheral surface 10A, the guide roller 28 and the holding plate 20 are fixed to the base 25 so that the positional relationship with the base 25 does not change. That is, the guide roller 28 and the pressing plate 20 are in a state in which the positional relationship does not change with each other. As a result, when the guide roller 28 is kept in contact with the outer peripheral surface 10A of the cylindrical tank 10, the distance between the inner surface 20A of the holding plate 20 and the outer peripheral surface 10A of the cylindrical tank 10 becomes constant. Therefore, for example, when the cylindrical tank 10 is rotated, the guide roller 28 suppresses the distance between the inner surface 20A and the outer peripheral surface 10A from fluctuating, which makes it easier to make the thickness of the heat insulating foam layer 12 uniform.

The axial direction of the guide roller 28 coincides with the axial direction X of the cylindrical tank 10. Therefore, when the guide roller 28 is in contact with the outer peripheral surface 10A of the cylindrical tank 10, it can rotate with the rotation of the tank 10, and the guide roller 28 can refer to the cylindrical tank 10 with respect to the cylindrical tank 10. It is prevented that extra force is applied.
Further, it is preferable that the guide roller 28 can be switched between being fixed to the base 25 and being displaceable. Therefore, the guide roller 28 may be appropriately displaced with respect to the base 25 before being brought into contact with the cylindrical tank 10. By displacing the guide roller 28 and then bringing it into contact with the tank 10, the distance between the inner surface 20A of the holding plate 20 and the outer peripheral surface 10A of the cylindrical tank 10 can be appropriately adjusted. Then, by adjusting the distance between the inner surface 20A of the holding plate 20 and the outer peripheral surface 10A of the cylindrical tank 10, the thickness of the obtained heat insulating foam layer can also be adjusted.

Further, in addition to the pressing plate 20, a winding roll 26, a supply roll 27, and the like are attached to the base 25. A face material 13 is wound around the winding roll 26. The supply roll 27 is arranged near the upper part of the injection space S. The face material 13 is unwound from the winding roll 26, guided by the supply roll 27, and supplied from the upper part of the injection space S toward the injection space S. In the injection space S, the face material 13 is arranged along the inner surface 20A of the holding plate 20. Depending on the type of the face material 13, an uncoiler or the like may be provided for feeding from the winding roll 26, and the supply speed may be appropriately adjusted.

Next, each step of the heat-shielding construction method will be described in sequence. First, in the present embodiment, the cylindrical tank 10 is placed on the turning roll 30 as described above. Further, as shown in FIGS. 2 and 3, the pressing plate 20 is installed so as to be separated from the outer peripheral surface 10S of the cylindrical tank 10 to form an injection space S. Further, as described above, the face material 13 is fed out from the winding roll 26 and arranged along the inner surface 20A of the pressing plate 20 in the injection space S.

At this time, liquid leakage prevention members 35A, 35B, 35C are arranged in the lower portion and both side portions of the injection space S, and the lower portion and both side portions of the injection space S are sealed by the liquid leakage prevention members 35A, 35B, 35C. To. The liquid leakage prevention members 35A, 35B, and 35C are foam molded products in the present embodiment and are elastically deformable. Therefore, the lower portion and both side portions of the injection space S are appropriately sealed. The liquid leakage prevention members 35A, 35B, and 35C may be fixed to, for example, the outer peripheral surface 10A of the cylindrical tank 10. The liquid leakage prevention members 35B and 35C may be provided over the entire circumference of the outer peripheral surface 10S. Further, the liquid leakage prevention member 35A may have a length corresponding to the width length of the holding plate 20.
The foam molded product is formed by processing the foam into a predetermined shape such as a columnar shape so that the lower portion and both side portions of the injection space S can be appropriately sealed. The foam molded product is preferably a urethane foam molded product. The liquid leakage prevention members 35A to 35C may be fixed to the outer peripheral surface 10A with an adhesive, an adhesive, an adhesive tape, or the like, or may be fixed to the outer peripheral surface 10A with a magnet or the like.

In this way, after the injection space S is sealed and the face material 13 is in a state along the inner surface 20A of the pressing plate 20, the foam stock solution R is supplied to the injection space S from the discharge port 22. At this time, as shown in FIG. 3, the discharge port 22 may be moved so as to reciprocate along the horizontal direction.
The foam stock solution R injected into the injection space S is foamed and hardened, adhered to and integrated with the face material 13 arranged along the inner surface 20A, and also adhered to the outer peripheral surface 10A of the cylindrical tank 10. Will be done.

Further, when the injection of the foam stock solution into the injection space S is started, the cylindrical tank 10 is rotated about the axis. As a result, the foam stock solution is injected into the injection space S while rotating the cylindrical tank 10. At this time, the cylindrical tank 10 is rotated so that the portion facing the presser plate 20 faces downward with respect to the presser plate 20. That is, as shown in FIG. 4, the foam stock solution R injected into the injection space S moves downward so as to move away from the discharge port 22 while foaming and hardening.
On the other hand, the foam stock solution R is continuously supplied from the discharge port 22 to the injection space S between the outer peripheral surface 10A and the inner surface 20A, and the cylindrical tank 10 has a heat insulating foam on the outer peripheral surface 10A over the entire circumference. Layer 12 will be formed. Further, while the foam stock solution is supplied, the face material 13 continues to be supplied along the inner surface 20A of the holding plate 20 in accordance with the rotation of the cylindrical tank 10, so that the surface on the surface of the heat insulating foam layer 12 is surfaced. The material 13 will be integrated (see FIG. 1).

As described above, the liquid leakage prevention members 35A, 35B, and 35C are fixed to the cylindrical tank 10. Therefore, when the cylindrical tank 10 is rotated, as shown in FIG. 4, the lower liquid leakage prevention member 35A also moves together with the cylindrical tank 10 and moves away from the injection space S. However, the foam stock solution R exists in the lower part of the injection section S, and the foam stock solution R does not leak from the lower part of the injection section S.
Since the liquid leakage prevention member 35A (foam molded product) becomes unnecessary when it is moved away from the pressing plate 20 as shown in FIG. 4, it may be appropriately removed from the cylindrical tank 10. Alternatively, a part of the heat insulating material may be formed while being attached to the outer peripheral surface 10A of the cylindrical tank 10.

In the present embodiment, the width of the holding plate 20 (that is, the length along the axial direction X) is sufficiently smaller than the length of the cylindrical tank 10 in the axial direction X. On the other hand, according to the above construction method, the heat insulating foam layer 12 is formed in a length approximately equal to the width of the pressing plate 20. Therefore, the heat insulating foam layer 12 formed by one rotation of the cylindrical tank 10 is usually only a part of the outer peripheral surface of the cylindrical tank 10.
Therefore, in the present embodiment, assuming that the heat insulating foam layers 12 formed by one rotation of the tank 10 are in one row, the heat insulating foam layers may be formed in a plurality of rows along the axial direction X of the cylindrical tank 10. .. By performing the plurality of rows, for example, the heat insulating foam layer 12 can be formed in most of the outer peripheral surface 10A of the tank 10 or substantially in the entire region.
However, if the cylindrical tank 10 is sufficiently small, a single row of heat insulating foams 12 may be formed.

Further, as described above, when the heat insulating foam layer 12 in the first row was formed, the liquid leakage prevention members 35B and 35C were arranged on both sides of the injection space S, but the heat insulating foam layers 12 in the second and subsequent rows In the formation, one side of the injection space S may be sealed by the already formed heat insulating foam layer 12, so that one of the liquid leakage prevention members 35B and 35C can be omitted.
When forming the heat insulating foam layer 12 in three or more rows, for example, after forming the first row, the heat insulating foam layer 12 in the third row is formed at a distance, and then the heat insulating foam layer in the second row is formed. If 12 is formed, both sides can be sealed by the already formed heat insulating foam layer when the second row heat insulating foam layer 12 is formed. Therefore, both the liquid leakage prevention members 35B and 35C can be omitted.
When the side portion is sealed with the already formed heat insulating foam layer 12, the injected foam stock solution and the already formed heat insulating foam layer 12 are integrated, so that between adjacent rows (heat insulating foam layers 12, 12). The mechanical strength at the joints is relatively good.

As described above, in the present embodiment, the heat insulating foam layer is formed by injecting the undiluted foam solution between the pressing plate 20 kept at a constant interval and the outer peripheral surface 10A of the tank 10, so that highly accurate thickness control can be performed. It is possible to form a heat insulating foam layer having a uniform thickness. Further, since the mist does not scatter because of the injection method, and the undiluted solution may be carried to the site instead of the foam for construction, the volume of the intermediate material is extremely reduced. Therefore, although it is possible to carry out on-site construction with good workability, the performance such as heat insulation of the heat-insulating structure is excellent.
Further, since the face material and the heat insulating foam layer can be integrated by injection molding without separately providing the face material sticking process, the workability is excellent even when the face material is attached. Further, the heat insulating foam layer is hardened at the time of injection molding to adhere to the face material, the already constructed foam layer, and the tank surface with high adhesive strength, so that it becomes easy to improve the peel strength, the interlayer strength, the mechanical strength, and the like. .. In addition, injection molding using a presser plate, that is, a mold, makes it possible to finish the surface smoothly.

In the above first embodiment, the face material 13 is provided in the heat shield structure, but the face material 13 may be omitted. When the face material 13 is omitted, the winding roll 26 and the supply roll 27 may be omitted, but the release sheet may be supplied from the winding roll 26 and the supply roll 27 instead of the face material 13. Good. At this time, the release sheet may be supplied along the inner surface 20A of the holding plate 20 as in the face material 13.
If the face material 13 is omitted, the foam stock solution comes into direct contact with the presser plate 20, so that the presser plate 20 and the foam stock solution are easily adhered. However, by supplying the release sheet, the presser plate 20 and the face material are easily adhered to each other. Adhesion with 13 can be prevented.
Examples of the release sheet include a fluororesin sheet made of a fluororesin such as ethylene tetrafluoroethylene and ethylene difluoride, and a resin sheet having excellent releasability such as a silicone resin sheet. Further, a release paper or a release film in which at least one surface of the paper base material or the resin film is release-treated with a silicone resin or the like may be used.

Further, even when the face material 13 is used, the release sheet may be supplied together with the face material 13 along the inner surface 20A of the pressing plate 20. For example, a laminate of the face material 13 and the release sheet may be wound around the winding roll 26, and the laminate may be unwound and supplied along the inner surface 20A of the presser plate 20. In this case, the release sheet is arranged on the inner surface 20 side of the pressing plate 20.
Further, the face material 13 and the release sheet do not need to be supplied from the same winding roll 26. For example, as shown in FIG. 5, a winding roll 31 different from the winding roll 26 is provided, and the same. The release sheet 32 supplied from the winding roll 31 and the face material 13 supplied from the winding roll 26 may be stacked and supplied along the inner surface 20A of the pressing plate 20.

As described above, when the face material 13 and the release sheet were supplied onto the inner surface 20A of the holding plate 20, even if the face material 13 was a cloth material, a mesh material, or the like and had a gap, it exuded from the gap. It is prevented that the foam stock solution R comes into contact with the inner surface 20A side of the holding plate 20. Therefore, it is possible to prevent a problem that the cured product of the foam stock solution R adheres to the pressing plate 20.
Therefore, when the face material 13 is a cloth material such as glass cloth, a mesh material such as glass mesh, or the like, it is preferable to supply both the face material 13 and the release sheet on the inner surface 20A of the pressing plate 20. ..

[Second Embodiment]
Next, the heat-insulating construction method of the second embodiment of the present invention will be described with reference to FIGS. 6 and 7. In the following description, the differences from the first embodiment will be mainly described, but the description thereof will be omitted if the configuration is the same as that of the first embodiment. Further, members having the same configuration are designated by the same reference numerals.
In the first embodiment, the heat insulating foam layer is formed once in the thickness direction, but in the present embodiment, it is formed a plurality of times in the thickness direction. That is, as shown in FIG. 6, the heat insulating foam layer includes an inner layer 42A on the cylindrical tank 10 side and an outer layer 42B arranged on the surface side of the inner layer 42A.

More specifically, first, a plurality of rows of heat insulating foam layers 42 to be inner layers 42A are formed along the axial direction X of the cylindrical tank 10. Here, in the inner layer 42A, a joint 45A is formed between the heat insulating foam layer 42 forming each row and the heat insulating foam layer 42 in the row adjacent to the heat insulating foam layer 42. The heat insulating foam layer 42 of the inner layer 42A may be formed in the same manner as in the first embodiment. A face material may be provided on the surface of the inner layer 42, but may be omitted as shown in FIG. 6, that is, the face material 13 is formed between the inner layer 42A and the outer layer 42B as shown in FIG. You don't have to.
On the other hand, when a face material is provided on the surface of the inner layer 42A (not shown in FIG. 6), a glass mesh or a glass cloth can be preferably used as the face material. By using a glass mesh or glass cloth, the adhesiveness between the inner layer 42A and the outer layer 42B is excellent, and the strength of the heat insulating foam layer 42 is further improved.

Next, the heat insulating foam layer 42 constituting the outer layer 42B may be formed on the inner layer 42A formed as described above. The heat insulating foam layer 42 constituting the outer layer 42B may be formed in the same manner as in the first embodiment, but at this time, the face material 13 is supplied along the inner surface 20A of the pressing plate 20 to supply the surface of the outer layer 42B. The face material 13 may be integrally formed. At this time, also in the outer layer 42B, the joints 45B are provided between the heat insulating foam layers 42 and 42 forming each row, but as shown in FIG. 6, they are arranged so as to be separated from the joints 45B and 45A. Just do it. That is, each joint 45A of the inner layer 42A and each joint 45B of the outer layer 42B may be arranged at different positions in the axial direction X of the cylindrical tank 10.
The joints 45A and 45B generally have lower mechanical strength than other parts, but by shifting as described above, it is possible to reduce the decrease in mechanical strength of the entire heat-insulating structure.
The type of the face material 13 provided on the surface of the outer layer 42B is as described above and is not particularly limited, but a metal plate such as an iron plate or a plastic sheet is preferable for the purpose of makeup and moisture proofing. Of course, the face material 13 provided on the surface of the outer layer 42B may be omitted.

In the above description, an example in which the heat insulating foam layer is formed twice in the thickness direction has been described, but even when the heat insulating foam layer is formed three times or more (that is, three or more layers are provided), at least one layer (that is, an inner layer) is described. ) And the joints of at least the other layer (outer layer) may be arranged so as to be offset from each other. However, it is more desirable that the joints of all layers are staggered.
When three or more heat insulating foam layers are provided, the face material provided on the surface of the outer layer constituting the outermost layer is a metal plate such as an iron plate or a plastic sheet for cosmetic and moisture-proof purposes, and the outermost layer. When a face material is provided on the surface of a layer other than the above, the face material is preferably a mesh material such as a glass mesh or a glass cloth, or a cloth material for the purpose of reinforcement.

In the present embodiment, by forming the heat insulating foam layer 42 a plurality of times in the thickness direction, it is possible to increase the thickness of the heat insulating foam layer as a whole. The overall thickness of the heat insulating foam layer in the second embodiment is appropriately adjusted according to the desired heat insulating performance and the like, but is, for example, 40 to 600 mm, and can be further increased to 600 mm or more. is there.

The heat insulating foam layer 42 in each row may be formed over the entire circumference in the circumferential direction as described above, but a joint (joint in the circumferential direction) is formed between the start point and the end point of the heat insulating foam layer formation in each row. .. Therefore, when the heat insulating foam layer is formed more than once in the thickness direction, as shown in FIG. 7, the joints 46A in the circumferential direction of the inner layer 42A and the joints 46A in the circumferential direction of the outer layer 42B are formed at the portions overlapping in the thickness direction. The joints 46B may be arranged so as to be displaced in the circumferential direction.
Even when the heat insulating foam layer is formed three times or more in the thickness direction (that is, three or more layers are provided), at least one layer (that is, the inner layer) of the joint in the circumferential direction and at least one other layer (outer layer) The joints may be arranged so as to be offset from the joints in the circumferential direction. However, it is more desirable that the joints of all the stacked layers in the circumferential direction are displaced.

Each of the embodiments described above is an example of the present invention, and various modifications can be made as long as the effects of the present invention are exhibited. For example, the winding roll 26 is attached to the base 25, but does not need to be attached to the base 25 and may be arranged at another position. Further, a release sheet or a face material may be supplied on the inner surface 20A of the pressing plate 20 by a member other than the winding roll 26 and the supply roll 27. Further, the guide roller 28 may be omitted. Since a certain thickness accuracy can be obtained without using the guide roller 28, a heat insulating foam layer having relatively good heat insulating performance can be obtained.

In the above embodiment, the liquid leakage prevention members 35A, 35B, and 35C at the lower part and both sides are fixed to the outer peripheral surface 10A of the tank 10, but the present invention is not limited to these embodiments. For example, the liquid leakage prevention member 35A may be fixed to the outer peripheral surface 10A of the cylindrical tank 10, and the liquid leakage prevention members 35B and 35C on both sides may be fixed to the holding plate 20. When the liquid leakage prevention members 35B and 35C on both sides are fixed to the holding plate 20, the liquid leakage prevention members 35B and 35C and the foam stock solution are easily adhered to each other, but they are adhered by supplying a release sheet or a face material. Can be constructed while preventing.
Further, although the example in which the foam molded product is used as the liquid leakage prevention member 35A, 35B, 35C has been described above, the liquid leakage prevention member 35A, 35B, 35C is not limited to the foam molded product, and other liquid leakage prevention members are prevented. It may be a member. For example, tubes, release sheets and the like can also be used.

The tube may be expanded by supplying air to the inside by an air pump or the like, and in the expanded state, seal either the lower portion or both side portions of the injection space S. The material of the tube is not particularly limited, but a material having excellent releasability such as a fluororesin such as ethylene tetrafluoroethylene and ethylene difluoride and a silicone resin may be used. Further, a surface material having excellent mold releasability such as fluororesin or silicone resin may be attached to the surface of the resin tube, or the surface of the resin tube may be subjected to a mold release treatment with a mold release agent such as silicone resin. You may. Further, as the air tube, a water supply hose made of resin reinforced with glass fiber may be diverted.

When the release sheet is used as a liquid leakage prevention member, the release sheet supplied along the inner surface 20A of the holding plate 20 as described above may be used as the liquid leakage prevention member. Specifically, a member that bends at least one of both side portions and the tip portion of the release sheet supplied along the inner surface 20A of the presser plate 20 to seal either both side portions or the lower portion of the injection space S. It is good to use as. When the side portion of the release sheet is bent, for example, a bending mechanism for bending both sides of the release sheet may be provided between the supply roll 27 and the injection space S.
Further, the release sheet may be supplied so as to cover the side portion of the injection space S from a release sheet supply roll (not shown) provided separately from the winding roll 26.

Further, the liquid leakage prevention members 35A, 35B, and 35C may be other than the foam molded product, the tube, and the release sheet, and may be, for example, a frame material having a foam sheet, a release sheet, or the like attached to the outer peripheral surface.
Further, the above-mentioned foam molded product, tube, mold release sheet, frame material and the like may be used in appropriate combination. For example, different members may be used for the lower liquid leakage prevention member 35A and the side liquid leakage prevention members 35B and 35C.

10 Cylindrical tank 10A Outer surface 11 Heat insulation structure 12,42 Insulation foam layer 13 Face material 20 Presser plate 20A Inner surface 22 Discharge port 25 Base 26, 31 Winding roll 27 Supply roll 28 Guide roller 30 Turning roll 32 Release sheet 35A , 35B, 35C Liquid leakage prevention member 42A Inner layer 42B Outer layer 45A, 45B, 46A, 46B Joint R Foam stock solution S Injection space

Claims (10)

A holding plate is installed so as to form an injection space between the outer peripheral surface and the outer peripheral surface of the cylindrical tank.
A heat-insulating construction method in which a heat-insulating foam layer is formed on the outer peripheral surface of a cylindrical tank by injecting the foam stock solution into the injection space while rotating the cylindrical tank and foaming the foam stock solution. The face material is supplied along the inner surface of the presser plate facing the outer peripheral surface, and the foam stock solution is injected into the injection space while supplying the face material, and the face material is applied to the surface of the heat insulating foam layer. The heat-insulating construction method according to claim 1, which is integrated. The heat-insulating construction method according to claim 2, wherein the face material is a glass cloth, a glass mesh, a metal plate or a plastic sheet. The heat-insulating construction method according to any one of claims 1 to 3, wherein a plurality of rows of the heat insulating foam layer are formed along the axial direction of the cylindrical tank. The heat-insulating construction method according to any one of claims 1 to 4, wherein the heat insulating foam layer is formed a plurality of times in the thickness direction. The heat insulating foam layer is formed in a plurality of rows along the axial direction of the cylindrical tank, and the heat insulating foam is formed in the thickness direction so that the joints between the rows of the inner layer and the joints between the rows of the outer layer are displaced. The heat-insulating construction method according to claim 5, which is performed a plurality of times. The heat-insulating construction method according to any one of claims 1 to 6, wherein a release sheet is supplied along the inner surface of the holding plate facing the outer peripheral surface. The heat-insulating construction method according to any one of claims 1 to 7, wherein liquid leakage prevention members are arranged on both sides of the injection space and at least one lower portion. The heat-insulating construction method according to claim 8, wherein the liquid leakage prevention member is any of a foam molded product, a tube, and a release sheet. The heat-insulating construction method according to any one of claims 1 to 9, wherein the guide roller is brought into contact with the outer peripheral surface and the holding plate is arranged at a constant distance from the outer peripheral surface.