JP3044605B2 - Heat insulation construction method for low temperature tank wall - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention forms a heat-insulating layer of hard urethane on the outer wall of a low-temperature tank such as liquefied natural gas (LNG) or liquefied petroleum gas (LPG), in particular, on the inner surface of the outer wall of the inner and outer double walls. For the heat insulation of the low temperature tank wall.

[0002]

2. Description of the Related Art When forming a heat-insulating layer on the wall surface of a low-temperature tank, a surface material such as a glass mesh is provided on the surface side of the heat-insulating layer of hard urethane in order to reinforce the surface of the heat-insulating layer, protect the surface, and finish the appearance. It is desirable to attach.

[0003] As described above, when a predetermined heat-insulating structure is constructed on the wall surface of a low-temperature tank using a heat-insulating layer made of hard urethane and a surface material, a method of spraying hard urethane foam directly on the wall surface has conventionally been adopted. More specifically, as shown in FIG. 6 (A), the particles directed toward the wall surface W by the blast device 31 carried by the worker M who has got on the gondola 30 which can move up and down and can move horizontally along the low-temperature tank wall surface W. After blasting the wall W by blasting, FIG.
(B) As shown in FIG.
Apply primer using 2 or the like.

Subsequently, as shown in FIG. 6C, a hard urethane spray 33 is set on the gondola 30, and the hard urethane foam PUF is applied to the wall surface W after the primer treatment by raising and lowering and moving the gondola 30 horizontally. After automatic spraying and foaming, the urethane foam P
As shown in FIG. 6 (D), the surface of the UF is cut using a special hand cutter 34 or the like so as to have a constant thickness. Let it be sucked.

Thereafter, as shown in FIG. 6E, the spray gun 36 held by the worker M on the gondola 30 is held.
Heat-insulating layer 3 made of urethane foam PUF
7 is coated with an adhesive 40, and FIG.
As described above, a surface material 38 such as a glass mesh is sequentially adhered to the surface of the heat-insulating layer 37 by cooperation of a plurality of workers M. Finally, as shown in FIG. 6 (G), the adhesive 40 is cured by heating from above the surface material 38 using a drier 39 or the like, and the surface material 38 is fixedly integrated with the surface of the heat insulating layer 37. Let it.

[0006]

FIG. 6 (A) shows the case of the above-mentioned conventional method for heat-insulating the wall surface of a low-temperature tank.
As shown in (G), not only many steps are required, but also each step is almost an artificial operation by an operator,
In particular, since the cutting of the urethane foam surface is difficult to machine and requires manual work, there is a problem that an enormous construction period and cost are required as a whole. In addition, it is inevitable that the working environment will be deteriorated by dust such as cutting chips generated when cutting the surface of the urethane foam, and particularly in the case of heat-proofing the inner surface of the outer wall of the inner and outer double walls, work in a narrow space is required. , The deterioration of the working environment due to dust is remarkable.

[0007] In addition, in order to finish the thickness of the applied heat-insulating layer without variation over the entire wall surface, it is necessary to make the thickness constant during the process of cutting the surface from urethane foam spraying. However, there is a problem that finishing such a fixed thickness requires experience and a considerably high level of skill for the operator, and the thickness accuracy is naturally limited.

[0008] The present invention has been made in view of the above-mentioned circumstances, and it is possible to form a heat-insulating layer of hard urethane and a surface material continuously and integrally with a wall surface, thereby significantly reducing the construction period and construction cost. It is an object of the present invention to provide a method for heat-insulating the low-temperature tank wall surface, which can improve the working environment and improve the thickness accuracy of the heat-insulating layer.

[0009]

According to a first aspect of the present invention, there is provided a method for heat-insulating a wall of a low-temperature tank, wherein the heat-insulating layer is formed by spraying hard urethane on the wall of the low-temperature tank. A method for heat-insulating a low-temperature tank wall surface in which a surface material is adhered to the surface of the heat-insulating layer, wherein the elevating body is capable of moving up and down along the wall surface of the low-temperature tank as the elevating body rises from a construction start position. While sequentially feeding the held surface material in a tension applied state, spraying hard urethane on the back surface side of the fed surface material, at the uncured stage where the sprayed hard urethane exhibits self-adhesive force to the wall surface. The surface material and the hard urethane are integrally bonded to the wall surface by pressing the sprayed hard urethane side against the wall surface side of the low-temperature tank.

According to the first aspect of the present invention having the above constitutional requirements, when the elevating body is raised from the construction start position of the wall surface of the low-temperature tank, the surface material held by the elevating body is reduced. In the uncured stage, the hard urethane is sprayed on the back side of the surface material to be unwound, and the sprayed hard urethane exhibits a self-adhesive force. By pressing the attached hard urethane side against the wall surface side of the low-temperature tank, the surface material and the hard urethane are integrally bonded to the wall surface. Thus, it is possible to mechanically and continuously construct a heat-insulating structure consisting of the formation of a heat-insulating layer of hard urethane and the application of a surface material for surface reinforcement, surface protection and appearance finishing of the heat-insulating layer. Is possible,
As a result, the construction period and construction cost can be reduced and labor can be saved, and the work environment can be improved because the cutting work of the urethane foam surface is not required. Furthermore, as long as the amount of hard urethane sprayed on the back surface side of the surface material per unit area is kept constant, the thickness of the heat-insulating layer formed by the hard urethane can be controlled to a constant value. The thickness accuracy of the heat-insulating layer can be improved without the need for skill.

The elevating body used in the method for heat-insulating a low-temperature tank wall according to the first aspect of the present invention has only a function of sequentially feeding a surface material in a tension-applied state, and is capable of blowing hard urethane. The attachment gun may be provided on another elevating body that moves up and down in synchronism with it, or may be carried by an operator who rides on the elevating body. A surface material supply roller for holding the surface material wound around the surface material so as to be able to be fed upward and supplied in a state where the back surface faces the opposite side to the wall surface of the low-temperature tank, and the upper surface of the surface material supply roller A reversing tool for reversing the surface material fed from the supply roller so that its front and back surfaces are switched, and a spray gun for spraying hard urethane on the back surface of the surface material reversed by the reversing device. By using the form of the gondola, it is possible to reliably easily construction to the fully automated one-step operation with high thickness precision insulation layer that upward movement of a single gondola as described above.

Further, as the surface material used in the method for heat-insulating the wall surface of the low-temperature tank, a glass mesh is used, and a release paper is attached to the surface side of the glass mesh. By applying tension to the surface material unwound by winding the release paper, it is used under conditions where the temperature change of the tank wall surface and the temperature difference between the inside and outside of the wall surface is large and a large thermal shock acts on the wall surface The glass mesh that absorbs and mitigates the thermal shock caused by the glass mesh does not cause damage such as cracks in the heat-insulating layer, while the glass mesh with the property that it is difficult to apply tension is given sufficient tension via release paper, There is no wrinkle or the like, and it is possible to carry out a heat-insulating work with a good finish in appearance.

Further, when the inner surface of the outer wall of the inner and outer double walls in the low temperature tank is to be constructed, dust is not generated in a narrow space between the inner and outer double walls. Therefore, the effect of improving the working environment is more remarkable.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view showing a configuration of a gondola (elevating body) used when implementing a method for heat-insulating a low-temperature tank wall according to the present invention. This gondola 1 is composed of upper and lower two-stage gondola sections 1A and 1B. Are supported by a horizontal traverser (not shown) and a rope 2 connected to a winch so as to be vertically movable and horizontally movable along a wall surface W of the low-temperature tank.

A glass mesh 3 as a surface material is wound in a roll shape on a lower gondola portion 1B of the two-stage type gondola 1 together with release paper 4 adhered to the surface side of the glass mesh 3 with a light adhesive force. By winding up the surface material supply roller 5 to be held and the release paper 4, the glass mesh 3 is sequentially turned upward in a state in which the back surface side is opposite to the wall surface W of the low-temperature tank and in a tension applied state. A release paper take-up roller 6 that can be taken out is provided.

On the other hand, the upper gondola portion 1A of the two-stage type gondola 1 is provided with a reversing tool for bending and reversing the glass mesh 3 and the release paper 4 fed from the supply roller 5 so that the front and back surfaces thereof are exchanged. A fixed platen 7 having an inverted character shape and a spray gun 8 for spraying hard urethane on the back side of the glass mesh 3 bent and inverted by the platen 7 and near the top of the bent portion are provided.

Next, a description will be given of a procedure for constructing a heat-insulating structure on the wall surface W of the low-temperature tank using the two-stage gondola 1 having the above configuration. As shown in FIG. 2, one end of the glass mesh 3, which is fed upward along with the release paper 4 from the supply roller 5 by the winding of the winding roller 6 and is inverted by the platen 7 so that the front and back are switched, It is fixed to the construction start position A of the wall surface W of the low-temperature tank.

In this state, when the gondola 1 is raised straight upward from the construction start position A, the glass mesh 3 and the release paper 4 are moved from the supply roller 5 with an appropriate tension in accordance with the rise. While being sequentially fed out, it is bent and inverted so that the front and back are reversed by the platen 7, and the back surface of the glass mesh 3 faces the wall surface W of the low-temperature tank in a parallel state at a predetermined interval. In the above gondola 1
As shown in FIG. 3, a hard urethane PUF is sprayed on the back side of the glass mesh 3 and near the top B of the bent portion from the spray gun 8 installed in the upper gondola section 1A.

The hard urethane PUF sprayed in this manner is in a stage before it is cured, that is, in an uncured stage in which self-adhesion to the wall surface W is exhibited, and the platen 7 is hardened.
When the glass mesh 3 moves along with the glass mesh 3 which is inverted and moves downward, and is in parallel with the wall surface W of the low-temperature tank, as shown in FIG. As a result, as shown in FIG. 4, the low-temperature tank wall W at the trace of the upward movement of the gondola 1 is adhered to the wall W integrally.
Heat-insulating layer 10 made of hard urethane PUF and heat-insulating layer 1 for surface reinforcement, surface protection and appearance finish of the heat-insulating layer 10
A heat-insulating structure 11 consisting of a glass mesh 3 integrally bonded to the surface 0 is installed.

Prior to the above-described heat protection, a plurality of rows of foamed urethane spacers 12 are previously bonded to the wall surface W of the low-temperature tank in parallel with each other at predetermined intervals in the horizontal direction as shown in FIG. By fixing, the wall surface W is divided into a plurality of parts, and the above-mentioned heat insulating structure is constructed while sequentially traversing the gondola 1 in the lateral direction with the divided wall parts Wa, Wb,.

In the above-described embodiment, the inverted gland-shaped platen 7 is fixedly installed as an inverting tool on the upper gondola portion 1A of the gondola 1 of the upper and lower two-stage type. Rollers may be provided.

[0022]

As described above, according to the first aspect of the present invention, only by raising and lowering the elevating body from the construction start position of the wall surface of the low temperature tank, the heat insulating layer made of hard urethane and the heat insulating layer are formed on the wall surface. A heat-insulating structure consisting of a surface material for surface reinforcement, surface protection and appearance finishing of the layer can be mechanically and continuously integrated. Therefore,
Compared to the conventional thermal insulation construction method described in detail at the beginning, the construction period and construction cost can be significantly reduced and labor can be saved.In addition, since the urethane foam surface cutting work is not required at all, especially inside and outside of low-temperature tanks Even when the inner surface of the outer wall of the double wall is to be constructed, there is no fear of generating dust in a narrow space between the inner and outer double walls, and the working environment can be greatly improved. In addition, the thickness and surface finish of the heat-insulating layer formed of hard urethane can be controlled to a constant level, and the thickness accuracy and surface finishing accuracy of the heat-insulating layer can be improved without the need for experience or advanced skill. It works.

In particular, as the elevating body used in the method for heat-insulating the low-temperature tank wall according to the first aspect of the present invention, a two-stage type gondola having a configuration as described in the second aspect is used. Accordingly, as described above, a heat insulating layer having high thickness accuracy and high surface finishing accuracy can be reliably and easily applied by a fully automatic one-step operation of raising a single gondola.

Further, as the surface material used in the above-described method for heat-insulating the low-temperature tank wall surface, a glass mesh having release paper adhered to the back surface thereof is used as described above. Absorbs and relaxes thermal shock caused by temperature changes and temperature differences between the inside and outside of the wall to prevent damage such as cracks in the heat-insulating layer. By applying tension, it is possible to carry out a heat-resistant construction with a good appearance in appearance without wrinkles or the like on the surface.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing a configuration of a gondola used for implementing a method for heat-insulating a low-temperature tank wall according to the present invention.

FIG. 2 is a schematic side view of a main part showing a state immediately before the start of thermal insulation work using the gondola.

FIG. 3 is an enlarged vertical cross-sectional side view of a main part for explaining a state of thermal insulation construction.

FIG. 4 is an enlarged vertical cross-sectional side view of a main part of a low-temperature tank wall surface after heat-insulating work.

FIG. 5 is a schematic cross-sectional view showing a state of a low-temperature tank wall surface before thermal insulation construction.

6 (A) to 6 (G) are schematic perspective views illustrating a conventional method for heat-insulating a low-temperature tank wall.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gondola of upper and lower two-stage type 1A Upper gondola section 1B Lower gondola section 3 Glass mesh (example of surface material) 4 Release paper 5 Surface material supply roller 7 Fixed platen (example of reversing tool) 8 Spray gun 10 Heat insulation layer W Low temperature Tank wall PUF sprayed hard urethane

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-27051 (JP, A) JP-A-58-94568 (JP, A) JP-A-58-80071 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) F17C 3/04 E04H 7/18 E04B 1/76

Claims (4)

(57) [Claims] 1. A method for heat-insulating a wall of a low-temperature tank, wherein hard urethane is sprayed on a wall of the low-temperature tank to form a heat-insulating layer, and a surface material is adhered to a surface of the heat-insulating layer. While sequentially feeding the surface material held by the elevating body with tension from the construction start position of the elevating body capable of ascending and descending along the tension applying state,
A hard urethane is sprayed on the back side of the fed surface material, and the sprayed hard urethane is pressed against the wall surface side of the low-temperature tank at an uncured stage where the sprayed hard urethane exhibits a self-adhesive force to a wall surface. A method for heat-insulating a low-temperature tank wall surface, wherein the surface material and the hard urethane are integrally bonded to the wall surface. 2. A surface for holding the surface material, which is wound in a roll shape, at the lower portion of the elevating body so as to be able to be fed upward and supplied so that the back surface thereof faces the opposite side to the wall surface of the low-temperature tank. A material supply roller is provided, and an upper part thereof has a reversing device for reversing the surface material fed from the surface material supply roller so that the front and rear surfaces thereof are interchanged, and a reverse surface of the surface material reversed by the reversing device. 2. The method for heat-insulating a low-temperature tank wall according to claim 1, wherein an upper and lower two-stage gondola equipped with a spray gun for spraying hard urethane is used. 3. A glass mesh is used as the surface material, and a release paper is attached to a surface side of the glass mesh, and tension is applied to the surface material fed by winding the release paper. 3. The method for heat-insulating a low-temperature tank wall according to 1 or 2. 4. The method for heat-insulating a low-temperature tank wall according to claim 1, wherein the wall surface of the low-temperature tank to be installed is the inner surface of the outer wall of the low-temperature tank having an inner and outer double wall.