KR200210989Y1 - heat insulator used in pipes for transferring low temperature materials - Google Patents

Abstract

Low temperature, including the inner insulation layer 120, the intermediate insulation layer 130, the outer insulation layer 140 is made of a polyisocyanurate foam at least a half (1/2) cylindrical shape is sequentially coupled to the outer peripheral surface of the pipe to which the low-temperature material is transported In the cold insulation structure of the material transfer pipe, the junction portion 150 of the inner insulation layer 120 and the intermediate insulation layer 130 is formed in a step shape, the junction gap 200 is formed in the junction portion of the outer insulation layer 140. The cold insulating material of the low temperature material conveying piping which is formed and inject | pours, spot-foams, and adhere | attaches a polyurethane stock solution to this junction gap is disclosed. According to the present invention, the inflow of air and water vapor from the outside is completely blocked so that problems such as freezing of the water vapor inside the heat insulating material and thereby peeling off the heat insulating material do not occur.

Description

Cooling insulation for pipes for low temperature material transfer {heat insulator used in pipes for transferring low temperature materials}

The present invention relates to a cold insulation material structure of a low temperature material conveying pipe, specifically, a pipe for transporting low temperature liquefied gas such as LNG, LPG, and LEG is wrapped and blocked from outside air to prevent cold storage of the material inside the pipe. It relates to a heat insulating material structure to be maintained.

Liquefied gases such as LNG, LPG and LEG are transported and stored in tanks at stockpiling bases, for example, from vessels and then supplied to each consumption area via pipes in the supply lines. At this time, the temperature of the liquefied gas transported through the piping pipe is very low as a very low temperature. If the temperature rises due to the temperature of the outside air during the transport over a long distance, vaporization of the liquefied gas occurs inside the pipe to ensure proper transport. Not only that, but the expansion of the internal pressure can damage the pipe and cause a fatal accident.

In consideration of this point, the heat insulating material is wrapped in the piping pipe to block external air. An example of such a conventional heat insulating material structure is illustrated in FIGS. 1 and 2.

Referring to the drawings, the insulation structure is an inner insulation layer 20 is primarily coupled to the outer circumferential surface of the transport pipe 10 to which the low-temperature material is transported, and the intermediate insulation layer 30 is sequentially bonded on the inner insulation layer 20. ) And an outer insulation layer 40. The inner (20), middle (30), and outer insulation layers (30) all have a polyisocyanurate (hereinafter referred to as PIR) foam in a half (1/2) cylindrical or quarter cylindrical shape. It is manufactured and bonded with a sealant 50.

The fiberglass reinforcing tapes 21 and 31 are wound on the inner insulation layer 20 and the intermediate insulation layer 30 so as to firmly support them. In addition, to prevent moisture permeation, the middle insulation layer 30 has a manila foil as a secondary vapor barrier layer 60, and the outer insulation layer 40 has a mastic composed of about 30% solids and about 70% volatiles. ), The primary vapor barrier membrane 70 is covered. On the vapor barrier layer 70, a jacket layer 80 made of stainless steel or the like is applied again as a metal protective film, and a tape 90 made of stainless steel is also finished on the jacket layer 80 to finish.

Figure 3 is a side cross-sectional view of a conventional cold insulation structure. As shown, the inner insulation layer 20, the intermediate insulation layer 30 and the outer insulation layer 40 sequentially coupled on the pipe 10 for transporting the low temperature material are connected in the longitudinal direction by the shrinkage connecting portion 100. . In other words, the PIR insulation material shrinks and expands in the longitudinal direction due to the temperature difference between when low-temperature liquefied gas flows inside the pipe, and as a result, dimensional error and distortion may occur. In order to flexibly absorb the contraction connection part 100 is interposed. Specifically, the inner insulation layer 20 is filled with a glass wool 100 with a thickness of 100 mm every 6 m maximum, and the middle insulation layer 30 and the outer insulation layer 40 with a thickness of 50 mm every 6 m maximum. A portion of the outer insulation layer 40 is covered with a butyl rubber material (not shown) for steam blocking.

By the way, in the conventional cold insulation structure as mentioned above, the joint part of the sealant 50 of the inner insulation layer 20, the intermediate | middle insulation layer 30, and the outer insulation layer 40 is linear, and external air and water vapor | steam are connected to this junction part gap. There is a risk of inflow. Moreover, the shrinkage connecting portion 100 fills the space by filling the glass wool and expands as described above. Furthermore, the primary vapor barrier membrane uses a mastic composed of about 30% of solids and 70% of volatiles, which is difficult to apply to a certain thickness and cannot completely block water vapor. It does not completely prevent the ingress of water vapor.

The external air and water vapor introduced as above freeze inside the insulation due to the low temperature of the liquefied gas, thereby lowering the insulation efficiency of the insulation. Moreover, this freezing eventually leads to damage and destruction of the insulation.

The present invention was devised to solve the above problems, and an object of the present invention is to provide a cold insulating material for a low temperature material conveying pipe whose structure is improved to completely block the inflow of air and water vapor from the outside.

1 is a partial cutaway perspective view showing the structure of the heat insulation of the conventional pipe.

2 is a cross-sectional view taken along the line II-II of FIG.

Figure 3 is a side cross-sectional view of the cold insulation of the contraction connection in the conventional pipe.

Figure 4 is a partially cut perspective view showing the structure of the cold insulation of the pipe according to the present invention.

5 is a cross-sectional view taken along the line V-V of FIG. 4.

Figure 6 is a side cross-sectional view of the cold insulation of the shrinkage connection portion according to the present invention.

<Description of main reference numerals in the drawings>

10,110 Pipe 20,120 Insulation layer 30,130 Insulation layer

40,140 Insulation layer 21,31,121,131 Insulating fiberglass tape

100,300..Glass Wool 160 .. First Vapor Barrier 170 .. Second Vapor Barrier

180.Jacket layer

In order to achieve the above object, the cold insulation material of the low temperature material conveying pipe according to the present invention is made of at least a half (1/2) cylindrical shape with a PIR foam, and the inner insulation layer is sequentially bonded to the outer peripheral surface of the pipe to which the low temperature material is conveyed. In the cold insulating material structure of the low-temperature material transfer pipe including an intermediate insulation layer, an outer insulation layer, the junction of the inner insulation layer and the intermediate insulation layer is characterized in that the step formed.

In addition, it is preferable that a bonding gap is formed at the junction of the outer insulation layer and a polyurethane foam is injected into the bonding gap and cured.

Preferably, a first vapor barrier layer is interposed between the intermediate insulation layer and the external insulation layer, and the first vapor barrier layer is formed of an aluminum thin plate coated on both sides with polyethylene.

More preferably, a second vapor barrier membrane is bonded on the outer insulation layer, and the second vapor barrier membrane is prepared by applying and curing FRP impregnated with a glass mat and a yarn cloth in a polyester resin. .

According to another embodiment of the present invention, a low-temperature material transfer including an inner insulation layer, an intermediate insulation layer, and an outer insulation layer that are manufactured in at least a half (1/2) cylindrical shape with a PIR foam and are sequentially coupled to a pipe outer circumferential surface to which the low temperature material is transferred. In the cold insulation of the pipe for use, the inner insulation layer and the intermediate insulation layer is provided with a shrinkage connection in the longitudinal direction, the shrinkage connection is formed by filling the glass wool in a predetermined gap, while the outer insulation layer is not cold insulation is not formed Insulation is provided.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 and 5 illustrate the cold insulation of the low temperature material transfer pipe according to a preferred embodiment of the present invention. Referring to the drawings, the cold insulation of the present invention includes an inner insulation layer 120, an intermediate insulation layer 130 and an outer insulation layer 140 are sequentially coupled to the outer peripheral surface of the transport pipe 110.

The heat insulation layers are made of the PIR foam as described above, are fabricated into a half (1/2) cylinder, and then bonded to each other. In this embodiment, but is made of a semi-cylindrical combination, but is not limited to this can be produced in at least two parts, that is, 1/3 cylindrical, 1/4 cylindrical.

According to a feature of the present invention, the junction portion 150 of the inner insulation layer 120 and the intermediate insulation layer 130 is in the shape of a staircase. The staircase junction 150 has superior airtightness as compared to the conventional straight junction (see 50 of FIG. 1), thereby minimizing the possibility of inflow of outside air. The stair joint 150 is preferably bonded with a joint sealant. Subsequently, the combined inner insulation layer 120 is wound using a glass fiber reinforced tape 121, preferably 898, of 3M, to be supported more firmly.

On the inner insulation layer 120, the intermediate insulation layer 130 of the same material is combined again in the same structure. At this time, the step junction portion of the intermediate insulation layer 130 is coupled to be located at a different point from the step junction portion of the inner insulation layer 120 is preferably further improved airtightness. The same fiberglass reinforcing tape 131 is wound on the intermediate insulation layer 130.

A first vapor barrier layer 160 is interposed between the intermediate insulation layer 130 and the outer insulation layer 140. The first vapor barrier layer 160 is an aluminum thin plate coated on both sides of polyethylene, and the adhesive is applied to an inner surface thereof so that the first vapor barrier layer 160 is completely in contact with the intermediate insulation layer 130.

After the first vapor barrier layer 160 is bonded, the same fiberglass reinforcing tape 131 is wound thereon.

According to another feature of the present invention, the outer insulation layer 140 does not have a stepped joint, but a joint gap 200 of about 20 mm is formed therebetween, and the polyurethane stock solution is injected into the joint gap 200. , Foamed on site and joined. Such polyurethane foams preferably have a density of 40-50 kg / m ³ , such as FINEpol-240 manufactured by Finetec. Injection of the polyurethane stock solution is made directly during construction in the field to seal the joint more securely, and a separate spacer may be employed to maintain a gap of about 20 mm. More specifically, the metalized polyester tape 201 is attached to the bonding gap 200 to prevent the foam from flowing around or spreading when the polyurethane stock solution is injected, and then the inside of the space. After injecting the polyurethane stock solution into the solution, the tape 201 is removed after curing.

The second vapor barrier layer 170 is coated on the outer insulation layer 200. The second vapor barrier layer 170 is manufactured by applying and curing a fiber reinforce plastic (FRP) impregnated with a glass mat and a yarn cloth to a polyester resin, for example, of Sewon Hwasung Co., Ltd. It can be manufactured using Polystar R-235SE polyester resin, CM300-104 glass mat of Owens Corning Korea Co., Ltd. and KN2100S nightcloth of Gangnam Precision. The second vapor barrier membrane 170 thus prepared has a water vapor transmission coefficient of almost zero to completely block the inflow of water vapor. The same material as the second vapor barrier layer 170 is partially applied to seal the portion after the polyurethane stock solution is injected and cured into the above-described junction gap 200.

The jacket layer 180 made of stainless steel is again coupled to the second vapor barrier layer 170, which is firmly coupled and supported by the stainless steel band 190 wound thereon. In addition, the surface bonding portion of the jacket layer 180 is bonded by a metal sealant to seal the inflow of air.

Figure 6 shows a side cross-sectional view of the cold insulation according to an embodiment of the present invention. According to another feature of the present invention, the inner insulation layer 120 and the intermediate insulation layer 130 is provided with a contraction connection portion 300 in the longitudinal direction, the inner insulation layer has a gap of 100mm every 6m up to a glass wool in this gap The middle insulation layer is filled with a gap of 50mm every 6m, and the glass wool is filled in this gap to form a shrinkage connection. Preferably, the interval between the contraction connection portion 300 of the inner insulation layer 120 and the intermediate insulation layer 130 is about 150mm is appropriate.

In addition, the present inventors have found that the outer insulation layer 140 is not provided with a contraction connection because the outer insulation layer 140 is hardly affected by the temperature of the liquefied gas flowing through the pipe 110. Specifically, Table 1 below shows one side of the PIR used as a heat insulator of the present invention in contact with liquid nitrogen at -192 ° C., and the other side was maintained at room temperature (30 ° C.), and then the temperature was measured according to the thickness of the PIR. to be.

Distance from liquid nitrogen (mm) Measured temperature (℃) 10 -174.6 20 -157.6 40 -122 60 -105 80 -92 100 -75 120 -54.6 140 -32 160 -21.7 180 16.2 190 27.2

As can be seen from the table, if the thickness of the inner insulation layer 120, the middle insulation layer 130 and the outer insulation layer 140 is 50mm, 100mm, 50mm respectively, the outer insulation layer 140 has almost no temperature deviation, so the separate shrinkage It is not necessary to have a connection. Therefore, as in the present invention, by not providing a separate contractive connection to the outer insulation layer 140, it is possible to completely eliminate the room for the air and water vapor flow.

According to the present invention, the joint portion of each heat insulating layer has a stepped shape, and adopts the first vapor barrier film 160 of aluminum sheet coated on both sides with polyethylene, and injects the polyurethane stock solution to the outer heat insulating layer 140, By using FRP having a moisture permeability coefficient of 0 as the second vapor barrier membrane 170, it is possible to block the inflow of air or water vapor from the outside into the pipe, thereby removing the icing and the insulation that has been a problem in the conventional cold insulation structure Damage, destruction, etc. can be prevented.

Claims (6)

Low temperature material including an inner insulation layer 120, an intermediate insulation layer 130, and an outer insulation layer 140 that are made of polyisocyanurate at least a half (1/2) cylinder and are sequentially bonded to the outer circumferential surface of the pipe through which the low temperature material is transported. In the cold insulation of the conveying piping, The junction 150 of the inner insulation layer 120 and the intermediate insulation layer 130 is a cold insulation of the low temperature material transfer pipe, characterized in that the step made. The cold insulating material according to claim 1, wherein a joint gap (200) is formed at a joint of the outer heat insulating layer (140), and a polyurethane stock solution is injected into the joint gap, followed by field foaming and bonding. 3. The method of claim 2, wherein a first vapor barrier layer 160 is interposed between the intermediate insulation layer 130 and the outer insulation layer 140, and the first vapor barrier layer 160 is coated with polyethylene on both sides thereof, and the inner surface thereof is adhesive. Cooling insulation, characterized in that consisting of a thin aluminum sheet. The method of claim 3, wherein a second vapor barrier layer 170 is coupled to the outer insulation layer 140, and the second vapor barrier layer 170 is formed of a glass mat and a yarn cloth on a polyester resin. Cooling insulation prepared by coating and curing the impregnated FRP. The method of claim 1, The inner insulation layer 120 and the intermediate insulation layer 130 is provided with a shrinkage connecting portion 300 in the longitudinal direction, and the shrinkage connecting portion is formed by filling glass wool in a predetermined gap, while the outer insulation layer 140 has a shrinkage connecting portion. Cold insulation, characterized in that not formed. The method of claim 5, wherein the inner insulation layer is filled with glass wool in the gap with a gap of 100mm every 6m, the middle insulation layer is filled with glass wool in this gap with a gap of 50mm every 6m. Cold insulation.