JP4849639B2 - Durable member and open rack LNG vaporizer according to seawater using the same - Google Patents

Description

The present invention, durability member used in open rack-type LNG vaporizing dexterity header pipe according to the open rack-type LNG vaporization dexterity heat transfer tube or seawater according to the seawater, and, open rack-type LNG according to seawater using the durability member It relates to a vaporizer.

  An open rack vaporizer (ORV) is applied to vaporize liquefied natural gas (LNG). The ORV is a heat exchanger that vaporizes LNG by heat exchange with seawater, which is a heat source. 2A and 2B are schematic views of the ORV, where FIG. 2A is a front view thereof, FIG. 2B is a cross-sectional view thereof, and FIG. 2C is a schematic diagram showing a welded joint between a heat transfer tube and a lower header tube.

  As shown in FIGS. 2A and 2B, seawater is stored in the trough 70 in the ORV 100. The outer surface of the heat transfer panel (heat transfer tube panel) 10 formed by arranging a large number of heat transfer tubes 20 in a panel shape and joining the header tubes (lower header tube 30 and upper header tube 40) is discharged from the trough 70. Seawater flows down from the top. On the other hand, LNG is sent to the lower header pipe 30 via the lower manifold 50, heated by heat exchange with seawater, and vaporized and raised in each heat transfer pipe 20 of the heat transfer panel 10. Then, natural gas is led out from the upper manifold 60 via the upper header pipe 40. Further, as shown in FIG. 2C, the lower part of the heat transfer tube 20 is welded to the lower header tube 30.

  In the ORV heat transfer tube 20, the vicinity of the welded joint (including the welded portion) with the header tube (the lower header tube 30 and the upper header tube 40) is subjected to changes in the metal structure such as compound precipitation due to welding, and is corroded. It is often easy to do. The lower header pipe 30 and the lower part of the heat transfer panel 10 (lower part of the heat transfer pipe 20) on the LNG introduction side are dissolved because the seawater of the heating source is low temperature (about 0 ° C) by LNG (about -160 ° C). The environment is highly corrosive due to high oxygen concentration. For this reason, wear due to corrosion in the vicinity of the welded joint between the heat transfer tube 20 and the lower header tube 30 is significant, which affects the life of the ORV 100. In addition, as described above, seawater due to heat exchange at the time of LNG vaporization (during operation) is constantly applied to the lower header pipe 30 and the heat transfer panel 10, so that the surface of the lower header pipe 30 and the heat transfer panel 10 is erosion-corrosion. The risk of metal wear due to unavoidable is inevitable.

Therefore, various proposals have been made regarding the anticorrosion technology of ORV.
For example, Patent Document 1 proposes a technique in which a sacrificial anticorrosive metal (Zn—Al alloy or the like) is formed on a heat transfer tube surface (aluminum base material surface) by thermal spraying or cladding, thereby improving corrosion resistance. Patent Document 2 proposes an open rack type vaporizer heat transfer tube or header tube in which an organic coating layer containing petrolatum is formed on the outer surface layer in order to obtain high corrosion resistance. Furthermore, in Patent Document 3, an uncured product of a liquid vinyl ester resin composition is applied to the surface of a steel structure and / or a concrete steel structure, a transparent resin sheet is overlaid on the coating film, and ultraviolet light is applied thereon. An anticorrosion method for a steel structure or a concrete steel structure in which the whole is bonded and integrated by irradiation is proposed.
Japanese Patent Laid-Open No. 5-16496 JP 2004-293811 A JP 2003-213461 A

However, the conventional ORV anticorrosion technology has the following problems.
In the anticorrosion by the formation of the sacrificial anticorrosive metal layer in Patent Document 1, the sacrificial anticorrosive metal layer is consumed significantly faster depending on the use environment, only by the application of the sacrificial anticorrosive metal layer by thermal spraying at the lower header tube or the lower part of the heat transfer panel. In many cases, the function could not be demonstrated. Moreover, in the corrosion protection by thermal spraying, there is a problem that the weld joint is insufficiently sprayed or the sacrificial corrosion-resistant metal layer contains defects and corrodes. Furthermore, when using a material in which a sacrificial anticorrosive metal layer is formed of a clad, it is necessary to remove the sacrificial anticorrosive metal layer at the welded joint between the heat transfer tube and the header tube, and thus a separate anticorrosion treatment is required.

  Although it is possible to form anti-corrosion coating such as tar epoxy paint, at the lower header and the lower part of the heat transfer tube (especially near the welded joint between the heat transfer tube and the lower header tube) There is almost no practical example because there is a problem that the anticorrosion paint is frozen and peeled off by the heat cycle by repeating with normal temperature.

  In the technique in Patent Document 2, since only the organic coating layer containing petrolatum has low hardness, the erosion-corrosion resistance is insufficient. In this case, even if a hard layer such as an epoxy resin, a fluororesin, or an acrylic resin is provided on the organic coating layer, it is frozen and peeled off by a thermal cycle as described above, so that erosion-corrosion resistance protection is achieved. It was not enough. In addition, when a defect (such as a crack generated by shrinkage of the resin due to freezing) occurs in these resin layers, it is considered that seawater enters from the generated defect and the crack is further promoted by the thermal cycle.

  The technique in Patent Document 3 is premised on use in a corrosive environment such as normal temperature, humidity, and salinity, and is assumed to be used in an extremely severe environment such as an extremely low temperature during LNG vaporization such as ORV. The durability is not clear at all. In addition, when defects occur in these resins, it is considered that seawater enters from the generated defects and further cracking is promoted by the thermal cycle.

  Thus, at the welded joint between the heat transfer tube on the LNG introduction side of the ORV and the header tube in the past, suppression of wear due to corrosion such as erosion-corrosion resistance, cryogenic temperature at the time of operation and stop (about -160 ° C) ) And the temperature near normal temperature (durability at repeated low temperatures), and suppression of growth of defects in the resin coating layer during use of ORV (defect growth suppression) There are almost no development cases.

The present invention has been made in view of the above-mentioned problems, and its purpose is to prevent wear due to corrosion, and to provide a durable member having repeated cryogenic durability and defect growth suppressing effects, and the use thereof. An object of the present invention is to provide an open rack LNG vaporizer related to seawater .

The durable member according to the present invention is an endurance used for an open rack type LNG vaporizer heat transfer tube related to seawater or an open rack type LNG vaporizer header tube related to seawater (hereinafter also referred to as an ORV heat transfer tube as appropriate). From a vinyl ester resin, which is a bisphenol-type glycidyl ether or a novolac-type glycidyl ether esterified with acrylic acid or methacrylic acid and added with a styrene monomer , on a part or all of the surface of the substrate. The resin coating layer is at least one selected from oxide particles, metal particles having a natural oxide film on the surface, and metal particles having an oxide film formed on the surface. , Particles having an average particle size of 0.05 to 10 μm (these oxide particles, natural oxide film on the surface) 0.1 to 10% by volume with respect to the total volume of the resin coating layer, and having a thickness of metal particles having a metal particle having an oxide film formed on the surface thereof, as appropriate) together it is 30μm or more 10mm or less, when mixing the metal particles in the resin coating layer, the oxygen atoms present on the surface of the metal particles is applied to the styrene groups in the resin of the resin coating layer, the styrene monomer product The defects produced are covered with a styrene monomer .

According to such a durable member, by having the resin coating layer having a thickness of 30 μm or more and 10 mm or less , durability such as impact resistance, erosion-corrosion resistance, and repeated cryogenic durability is improved. Further, by containing a predetermined amount of particles having a predetermined average particle diameter in the resin coating layer, oxygen atoms present on the particle surface act on the styrene group in the resin of the resin coating layer. Thereby, a styrene monomer produces | generates and the adsorption / desorption reaction of the styrene monomer in a resin coating layer is accelerated | stimulated.

Further, in the durable member according to the present invention, at least one type of fiber selected from glass fiber, carbon fiber, and boron fiber (hereinafter also referred to as reinforcing fiber as appropriate) in the resin coating layer, It is characterized by containing 20 mass% or more and 60 mass% or less with respect to the total mass of the resin coating layer.

In this case, the fibers contained in the resin coating layer, off Lake like fiber, and is preferably at least one selected from fibers, matted dispersed in nonwoven fabric.

According to such a durable member, by forming the resin coating layer containing the reinforcing fiber, the strength against the impact from the outside world is further improved, and the invasion of the corrosive component from the outside world is achieved. Is prevented. Furthermore, the use of full rake-like or matted fibers, penetration of corrosive components from the outside is easily prevented more. Furthermore, it becomes easy to add the reinforcing fibers to the resin coating layer, and it becomes easy to obtain the reinforcing fibers.

  Furthermore, the durable member according to the present invention is characterized by having an Al alloy sprayed coating layer as an intermediate layer between the base material and the resin coating layer.

  According to such a durable member, by providing the sprayed coating layer of the Al alloy as the intermediate layer, the resin coating layer penetrates into the pores formed on the surface of the sprayed coating layer, and an anchoring action is generated. Thereby, the adhesiveness of a resin coating layer and a thermal spray coating layer improves. Moreover, when the resin coating layer is lost, the sprayed coating layer having a potential lower than that of Al of the base material is eluted to prevent corrosion of the base layer (base material).

The open rack type LNG vaporizer according to the present invention uses the durable member described above.
According to open rack-type LNG vaporizers according to such seawater, the header pipe of the open rack type LNG vaporizers according to the heat transfer tubes or seawater open rack-type LNG vaporizers according to seawater, the durability member of the present invention Since it uses, it becomes an open rack type LNG vaporizer concerning the seawater excellent in durability.

According to the durable member of claim 1 of the present invention, the outer surface has the resin coating layer for improving the durability, so that it is sufficient for an impact from the outside assumed in a normal use environment. It has a strong strength. Further, even in the vicinity of the welded joint portion between the heat transfer tube on the LNG introduction side and the header tube in the open rack LNG vaporizer relating to seawater, wear due to erosion-corrosion hardly occurs, and further, excellent repeated low-temperature durability. And when it has a defect growth inhibitory effect and a defect arises in the resin coating layer, the produced defect is repaired effectively (self-repair). Therefore, it is possible to increase the life of the open rack-type LNG vaporizing dexterity header pipe according to the open rack-type LNG vaporization dexterity heat transfer tube or seawater according to the seawater, a long life of the open rack type LNG vaporizers according to seawater as a result can do.

  According to the durable member of claim 2 of the present invention, by forming the resin coating layer containing the reinforcing fiber, it is possible to ensure a sufficient strength against an impact from the outside, and the resin. Since the reinforcing fibers contained in the coating layer have a barrier effect against the entry of corrosive components from the outside, wear due to corrosion is less likely to occur, and durability is further improved.

  According to the durable member of the third aspect of the present invention, by using the reinforcing fiber having a predetermined shape, the barrier effect against the intrusion of the corrosive component from the outside is further increased, and the durability is further improved. Moreover, it becomes easy to contain a reinforced fiber in a resin coating layer, and also a reinforced fiber can be obtained easily and cheaply.

  According to the durable member of claim 4 of the present invention, since the adhesion between the resin coating layer and the thermal spray coating layer is improved by providing the Al alloy thermal spray coating layer as the intermediate layer, the resin coating layer is peeled off. It becomes difficult. Moreover, the corrosion resistance of the base material itself of the durable member is improved by the sacrificial anticorrosive action of the intermediate layer which is an Al alloy.

According to open rack-type LNG vaporizers according to seawater according to claim 5 of the present invention, the header tubes open rack-type LNG vaporizers according to the heat transfer tubes or seawater open rack-type LNG vaporizers according to seawater, the present invention Therefore, the durability of the heat transfer tube or the header tube is improved, and the durability of the open rack LNG vaporizer related to seawater is improved. In particular, at the welded joint between the heat transfer tube on the LNG introduction side and the header tube, it is possible to improve the effect of suppressing wear due to erosion-corrosion, repeated cryogenic durability, and suppressing the defect growth of the resin coating layer. it can.

Next, durability member according to the present invention with reference to the drawings, and, with the open rack-type LNG vaporizers according to the seawater will be described in detail. In the drawings to be referred to, FIGS. 1A and 1B are schematic cross-sectional views showing the configuration of a durable member, and FIG. 2 is a schematic view of an open rack LNG vaporizer (ORV) according to seawater . (A) is the front view, (b) is the sectional view, (c) is a mimetic diagram showing the welded joint part of a lower header pipe and a heat exchanger tube.

As shown in FIG. 1 (a), durability member 1a is used in a open rack-type LNG vaporizing dexterity header pipe according to the open rack-type LNG vaporization dexterity heat transfer tube or seawater according to the seawater (ORV heat transfer pipe) There is a resin coating layer 3 made of a vinyl ester resin on part or all of the surface of the substrate 2.
Each configuration will be described below.

≪Durable material≫
<Base material>
The material of the base material 2 is not particularly limited as long as it is used for the ORV heat transfer tube, but the material of the base material 2 of the ORV heat transfer tube is usually 3000 series, 5000 series, or 6000 series aluminum alloy. Used.

<Resin coating layer>
The resin coating layer 3 is made of a vinyl ester resin and is formed on a part or all of the surface of the substrate 2.
In addition, forming on a part of the surface means impact resistance, erosion-corrosion resistance, repeated cryogenic durability, defect growth inhibitory property, etc. without forming the resin coating layer 3 on the entire surface of the substrate 2. As long as durability can be exhibited, the base material 2 may have a portion that is not covered with the resin coating layer 3 and may have a portion where the base material 2 is exposed.
In addition, the resin coating layer 3 is preferably formed in a portion where the base material 2 is severely worn and deteriorated.

  By forming the resin coating layer 3 made of vinyl ester resin on the outer surface of the base material 2 of the durable member 1a, impacts from the outside and defects that occur during use of the ORV (for example, seawater used during heat exchange) Erosion-corrosion due to the flow of the liquid) and durability against heat cycles due to repeated low temperatures and temperatures near room temperature.

The main component of the resin constituting the resin coating layer 3 is a vinyl ester. The vinyl ester resin is sometimes called an epoxy acrylate resin, and various types of epoxy compounds are esterified with acrylic acid or methacrylic acid, and a polymerizable monomer is added to form an addition polymerization type. The epoxy compound to be a component of the raw material, typically bisphenol glycine di ether or novolak glycine di ether has been widely used, The present invention may be used any type of vinyl ester resin.

The resin coating layer 3 is at least one selected from oxide particles, metal particles having a natural oxide film on the surface, and metal particles having an oxide film formed on the surface, and the average particle size is 0. .05 to 10 μm of particles (particles 4) are contained in an amount of 0.1 to 10% by volume based on the total volume of the resin coating layer 3.
In addition, the metal particle which has an oxide film (natural oxide film) means the metal particle which has the surface oxide layer on the surface of the metal particle, and was covered with this surface oxide layer.
In addition, the natural oxide film is an oxide film that is inevitably generated on the metal surface, not actively oxidized on the surface.

When the particles 4 are mixed in the resin coating layer 3, oxygen atoms present on the surface of the particles 4 act on styrene groups in the resin of the resin coating layer 3 to generate styrene monomers, and the resulting defects are coated with the styrene monomers. The And the adsorption-desorption reaction of the styrene monomer in the resin coating layer 3 is accelerated | stimulated, a defect growth inhibitory effect is expressed, and the produced defect is self-repaired.
That is, such an effect is considered to be derived from an oxide or an oxide film (natural oxide film) formed on the surface. Accordingly, the metal particles may be in an untreated state, but even those that are positively oxidized, such as heating in an oxidizing atmosphere, are effective.

However, if the average particle diameter of these particles 4 is less than 0.05 μm, it is difficult to obtain the particles 4, and even if they can be obtained, there is a problem that they are very expensive and costly. On the other hand, if it exceeds 10 μm, the adsorption / desorption reaction of the styrene monomer does not occur well, and the effect of mixing the particles 4 is not exhibited.
If the content of these particles 4 is less than 0.1% by volume, the oxygen atoms acting on the styrene group are insufficient, the adsorption / desorption reaction of the styrene monomer in the resin coating layer 3 is not promoted, and the defect growth suppressing effect is obtained. descend. On the other hand, if it exceeds 10% by volume, the effect of mixing and lowering the effect of mixing the particles 4 occurs, and the cost increases.

Examples of the particles 4 include those composed of titania, silica, alumina, zirconia, zinc oxide, etc. as the oxide particles 4, and examples of the metal particles 4 having an oxide film (or natural oxide film) include nickel. (Nickel oxide), tungsten (tungsten oxide), and the like can be mentioned, but the usable particles 4 are not limited to these, and any particles 4 having the same form may be used. But you can.
In addition, about the measurement of the average particle diameter of the particle | grains 4, although it can carry out by the method of observing the particle | grains 4 using an optical microscope or a scanning electron microscope (SEM), the average particle diameter 0 generally marketed is used. .5 to 10 μm particles 4 may be used.

  Further, in order to provide the resin coating layer 3 with durability such as excellent impact resistance, erosion-corrosion resistance, repeated cryogenic durability, and defect growth suppression, the thickness of the resin coating layer 3 is 30 μm or more. It is necessary to. As will be described later, in consideration of the case where the reinforcing fiber 5 is contained, the thickness of the resin coating layer 3 is preferably 40 μm or 50 μm or more. Moreover, when the thickness of the resin coating layer 3 is less than 30 μm, the particles 4 mixed in the resin coating layer 3 are dispersed non-uniformly, and it is difficult to obtain the effect of mixing the particles 4.

  On the other hand, during ORV operation, the LNG introduction side is at a very low temperature and the discharge side is at room temperature, resulting in a large temperature difference, and the heat transfer panel is deformed when the operation is stopped. Further, since subtle vibrations also occur during operation, if the resin coating layer 3 is too thick, the heat exchange with seawater decreases, and deformation due to temperature differences and vibration during operation cannot be followed. For these reasons, the thickness of the resin coating layer 3 is preferably 10 mm or less, more preferably 5 mm or less, and even more preferably 3 mm or less.

Regarding the measurement of the thickness of the resin coating layer 3, first, a test piece is prepared by the same method as that for forming a heat transfer tube or a header tube in an actual ORV, and three samples are cut out from the test piece in the thickness direction. . Next, this is mirror-polished and observed using an optical microscope (50 times magnification), and the smallest of the obtained thicknesses is defined as the thickness of the resin coating layer 3.
The resin coating layer 3 may have a laminated structure of two or more layers in order to improve strength and durability.

Here, in the durable member 1a, it is preferable that the resin coating layer 3 contains at least one fiber (reinforced fiber 5) selected from glass fiber, carbon fiber, and boron fiber.
By containing these reinforcing fibers 5 in the resin coating layer 3, it is possible to secure a sufficient strength against impacts from the outside and to provide a barrier effect against the intrusion of corrosive components from the outside.

  The content of the reinforcing fiber 5 is 20% by mass or more with respect to the total mass of the resin coating layer 3. When the reinforcing fiber 5 is contained in an amount of 20% by mass or more, wear of the heat transfer tube and the header tube is reduced. Preferably it is 30 mass% or more. On the other hand, if the reinforcing fiber 5 contained in the resin coating layer 3 is too much, the toughness of the resin coating layer 3 is impaired, so the content of the reinforcing fiber 5 is 60% by mass or less, preferably 50% by mass or less.

The content of the reinforcing fiber 5 in the resin coating layer 3 is such that the test piece is prepared by the same method as that for forming the heat transfer tube or the header tube in the actual ORV, and the dry mass of the formed resin coating layer 3 is as follows. And the ratio of the mass of the reinforcing fiber 5 is obtained and obtained as an average value measured five times. When measuring after forming the resin coating layer 3 containing the reinforcing fibers 5, the resin coating layer 3 was taken from the test piece, the resin coating layer 3 is thermally decomposed at a differential indicates difference thermobalance, etc., it was collected It can be determined from the ratio between the mass of the resin coating layer 3 and the mass of the remaining reinforcing fibers 5. Further, the resin coating layer 3 collected with a solvent such as chloroform, ether, benzene or the like is dissolved, and it can be determined from the ratio between the mass of the collected resin coating layer 3 and the mass of the remaining reinforcing fibers 5.

  The shape of the reinforcing fiber 5 may be spherical or rod-like, but in order to increase the barrier effect of the entry of corrosive components from the outside more effectively, it may be flake-like (scale-like (chip-like)) or mat-like. preferable. Moreover, you may use the reinforcing fiber layer which combined the flake-shaped reinforcing fiber 5 and the mat-shaped reinforcing fiber 5. FIG.

Further, the reinforcing fiber 5 is made of a flake fiber having a short side length of 20 μm or more, a long side length of 30 μm or more, and a thickness of 1 μm or more, and a mat-like fiber in which short fibers having a diameter of 5 μm or more are dispersed in a nonwoven fabric. It is preferable that at least one selected.
Such a reinforcing fiber 5 may be a commercially available glass flake or a mat-like glass fiber because of its availability.

In addition, the upper limit of the size of the reinforcing fiber 5 is not particularly defined, and the reinforcing fiber 5 may be contained in the resin coating layer 3 and may be used without departing from the gist of the present invention.
Moreover, what is necessary is just to judge about the magnitude | size of the reinforced fiber 5 as a parameter | index displayed on the commercial item.
If such a reinforcing fiber 5 is used, the reinforcing fiber 5 can be easily and inexpensively obtained, and the reinforcing fiber 5 can be easily contained in the resin coating layer 3.

  The resin coating layer 3 preferably has a laminated structure by alternately depositing vinyl ester resin and reinforcing fibers 5 formed in layers. By making the resin coating layer 3 have a laminated structure, the barrier effect against the impact from the outside world and the strength and the invasion of corrosive components is improved.

Here, as shown in FIG. 1 (b), the durable member 1 b further includes an Al alloy sprayed coating layer 6 as an intermediate layer between the base material 2 and the resin coating layer 3. Also good.
<Sprayed coating layer>

  By providing the Al alloy sprayed coating layer 6 as an intermediate layer, the resin coating layer 3 penetrates into the pores formed on the surface of the sprayed coating layer 6 and exhibits an anchor effect. Adhesion with the intermediate layer 6 is improved. Even if the resin coating layer 3 is missing, the intermediate layer 6 having a lower potential than the Al of the base material 2 is eluted, so that the base layer (base material 2) is obtained by the sacrificial anticorrosive action of the intermediate layer 6. Has the effect of preventing corrosion.

As the Al alloy constituting the sprayed coating layer 6, for example, an Al—Zn alloy, an Al—Mg alloy, an Al—Zn—Mg alloy, or the like can be used. Moreover, when using an Al-Zn alloy, an Al-2 mass% Zn alloy is mentioned, for example. For the above reason, the sprayed coating layer 6 needs to be a base metal (having a larger ionization tendency) than the base material 2.
The thickness of the sprayed coating layer 6 is not particularly specified, but may be about several tens of μm to several mm.

  As a manufacturing method of the durable members 1a and 1b, the resin coating layer 3 can be formed by a normal means using dipping, brushing, spraying or the like. Moreover, the particle | grains 4 and the reinforced fiber 5 are made uniform by adding and mixing in resin. For the intermediate layer 6, thermal spraying (frame spraying, electric spraying, high-speed flame spraying, etc.) can be mainly used. In addition, the manufacturing method of durable member 1a, 1b is not limited to these, What kind of method may be used if the effect similar to this invention is acquired by the method applied normally.

≪Open rack type LNG vaporizer related to seawater≫
The open rack type LNG vaporizer according to the seawater according to the present invention uses the above-described durable member.
Header tube open rack-type LNG vaporizers according to the heat transfer tubes or seawater open rack-type LNG vaporizers according to seawater, the use of durable member of the present invention, the durability of the open rack type LNG vaporizers according to seawater In particular, durability at the welded joint between the heat transfer tube on the LNG introduction side and the header tube is improved.

As the open rack type LNG vaporizer according to the seawater according to the present invention, a configuration of a generally used open rack type vaporizer may be used except that the durable member of the present invention is used. For example, FIG. What is necessary is just to set it as a structure as shown to (a)-(c).
That is, the heat transfer tube 20 produced using the durable members 1a and 1b of the present invention (see FIGS. 1A and 1B) and the header tube (the lower header tube 30 and the upper header tube 40) are welded and joined. Then, the open rack type LNG vaporizer 100 related to seawater is produced.
In addition, since it is as having demonstrated the structure and effect | action of the open rack type LNG vaporizer 100 which concerns on the seawater shown to Fig.2 (a)-(c), description is abbreviate | omitted here.

Next, the durable member according to the present invention and the open rack type LNG vaporizer according to seawater will be specifically described with examples and comparative examples.
[First embodiment]
Various particles shown in Table 1 were mixed in a commercially available vinyl ester resin (Lipoxy R-833DA manufactured by Showa Polymer Co., Ltd.), and then the resin was coated on an aluminum alloy (A5083) to form a resin coating layer. Next, the test piece after coating was scratched with a knife so as to reach the metal substrate. In order to examine the durability, the test piece thus produced was immersed in artificial seawater at 30 ° C., and a corrosion test was performed. The test time was 48 hours, the corrosion resistance was obtained from the AC impedance method, and the corrosion resistance (durability) was evaluated. Since the area of the scratch portion differs depending on the test piece, a corrosion resistance ratio obtained by dividing the corrosion resistance at each time by the corrosion resistance immediately after immersion was used. That is, although the load at the time of applying a scratch is constant, the length is not constant within a strict range, so the area may be different for each test piece. Therefore, in order to exclude these effects, the value of “corrosion resistance ratio” was used.

The corrosion resistance (durability) evaluation was performed by comparing the corrosion resistance ratio before and after the test because the applied scratch portion was repaired by the adsorption / desorption reaction of the styrene monomer, thereby increasing the corrosion resistance. Here, it carried out by calculating | requiring the average value of the corrosion resistance ratio after 12 hours after a test start. Specifically, the average value of the corrosion resistance ratio after 12, 24, 36, and 48 hours was obtained. A sample having an average value exceeding 1.0 was judged to have good corrosion resistance (durability), and a sample having an average value of 1.0 or less was judged to have poor corrosion resistance (durability).
These results are shown in Table 1. In Table 1, those not satisfying the claims of the present invention are indicated by underlining the numerical values and the like.

As shown in Table 1, Experiment No. Since Nos. 1 to 23 satisfied the configuration of the present invention, the average value of the corrosion resistance ratio after 12 hours was improved as compared with the case of the resin alone (Experiment No. 27), and the self-healing property was improved. As a result, the durability was good.

  In contrast, Experiment No. In No. 24, since the mixed particles did not have oxygen atoms, the corrosion resistance ratio was reduced, and the desired effect could not be exhibited, resulting in poor durability. Experiment No. In No. 25, since the average particle diameter of the mixed particles was too large, the corrosion resistance ratio was decreased and the desired effect could not be exhibited, and the durability was inferior. Experiment No. In No. 26, since the content of the mixed particles was excessive, the corrosion resistance ratio was decreased and the desired effect could not be exhibited, and the durability was inferior. Experiment No. Since No. 27 did not contain particles in the resin, the desired effect could not be expressed and the durability was poor. Experiment No. In No. 28, since the resin coating layer was thin, the particles were dispersed non-uniformly in the resin, so that the desired effect could not be exhibited and the durability was poor.

[Second Embodiment]
Next, considering the actual use situation of the ORV heat transfer tube or the header tube, the durability when the reinforcing fiber was contained in the resin coating layer was examined. First, the surface of the aluminum alloy (A5083) is roughened by shot blasting (alumina # 16-20) (arithmetic mean roughness Ra = 20-40 μm), and on top of that, a part thereof is an Al—Zn alloy. The thermal spray coating consisting of was coated to a coating thickness of about 300 μm.

Under the conditions shown in Table 2, a resin coating layer (reinforced fiber-containing resin coating) containing a predetermined amount of reinforcing fibers (see Table 2) using glass fibers, carbon fibers, or boron fibers mixed with particles in the resin Layer). About some, the resin coating layer was produced, without mixing a reinforced fiber. The resin coating layer and the reinforcing fiber-containing resin coating layer are composed of the above-described vinyl ester resin (Showa Polymer's Lipoxy R-833DA), surface layer protective resin (Showa Polymer's Lipoxy R-802), and reinforcing fibers. (In the case of a reinforced fiber-containing resin coating layer) and an aluminum alloy. For the two or more layers, the resin and the reinforcing fiber (in the case of the reinforcing fiber-containing resin coating layer) were formed into a laminated structure and formed on the aluminum alloy so that the resin was on the surface. Experiment No. For No. 39, the resin coating layer that does not contain reinforcing fibers has a two-layer structure.
In addition, about some test pieces, the alloy sprayed coating layer of Al-2 mass% Zn was provided as an intermediate | middle layer.

  This test piece was subjected to a cryogenic combined corrosion test 60 times with one cycle of 35 ° C., 5% saline spraying environment (23 hours) and liquid nitrogen immersion (1 hour), containing a resin coating layer and reinforcing fibers. The durability of the resin coating layer was investigated. After 5 times, 30 times, and 60 times of the cycle test, the resin coating layer and the reinforcing fiber-containing resin coating layer were observed for cracking and peeling.

Durability evaluation is good for those in which cracking or peeling did not occur in 60 cycles, excellent in durability (◎), those in which cracking or peeling occurred within 60 cycles within 60 cycles (○) More than 5 cycles, cracked or peeled off within 30 cycles, slightly good (△), cracked or peeled off within 5 cycles, poor (×) It was judged.
These results are shown in Table 2. In Table 2, those not satisfying the claims of the present invention are indicated by underlining numerical values and the like.

  As shown in Table 2, Experiment No. Nos. 29 to 31 satisfy the configuration of the present invention and have an intermediate layer, so that the reinforcing fiber-containing resin coating layer does not crack, crack, peel off, or the like even after 60 cycles of the cycle test. Was excellent and very durable. Experiment No. 32 and 33 satisfy the configuration of the present invention and have an intermediate layer, and thus have high durability. However, the shape of the reinforcing fiber is not preferable, so the durability is not excellent and good. Experiment No. The result was slightly inferior to 29-31.

  Experiment No. No. 34 has high durability in order to satisfy the configuration of the present invention, but does not have an intermediate layer. Therefore, the durability is not excellent and is good. The result was slightly inferior to 29-31. Experiment No. Nos. 35 to 38 satisfied the configuration of the present invention, and had an intermediate layer, so had high durability and good durability. However, experiment no. Compared to 29-31, the number of layers is small, so The result was slightly inferior to 29-31.

  Experiments Nos. 39 and 40 have a predetermined amount of particles mixed in the resin, but have no reinforcing fibers, and therefore have slightly higher durability. It was inferior to 29-38.

  In contrast, Experiment No. No. 41 has poor durability because the mixed particles do not have oxygen atoms. Experiment No. No. 42 had poor corrosion resistance because the average particle size of the mixed particles was too large. Experiment No. Since No. 43 did not contain particles in the resin, the corrosion resistance was poor. Experiment No. No. 44 had poor durability because the content of the mixed particles was excessive. Experiment No. No. 45 had poor durability because the resin coating layer was thin.

As mentioned above, although the durable member which concerns on this invention, and the open rack type | mold LNG vaporizer which concerns on the seawater using this were demonstrated in detail, showing the best embodiment and an Example, the meaning of this invention is content mentioned above The scope of rights should be broadly interpreted based on the description of the scope of claims. Needless to say, the contents of the present invention can be widely modified and changed based on the above description.

(A), (b) is a cross-sectional schematic diagram which shows the structure of a durable member. It is the schematic of the open rack type LNG vaporizer (ORV) which concerns on seawater , (a) is the front view, (b) is the sectional drawing, (c) is the welding joint part of a lower header pipe and a heat exchanger tube. It is a schematic diagram shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a, 1b Durable member 2 Base material 3 Resin coating layer 4 Particle 5 Reinforcement fiber 6 Thermal spray coating layer (intermediate layer)
10 Heat transfer panel (heat transfer tube panel)
20 heat transfer tube 30 lower header tube 40 upper header pipe 50 lower manifold 60 open rack-type LNG vaporizers according to the upper manifold 70 trough 100 seawater (ORV)

Claims (5)

A durable member used in open rack-type LNG vaporizing dexterity header pipe according to the open rack-type LNG vaporization dexterity heat transfer tube or seawater according to the seawater,
Part or all of the surface of the substrate has a resin coating layer made of a vinyl ester resin obtained by esterifying bisphenol-type glycidyl ether or novolac-type glycidyl ether with acrylic acid or methacrylic acid and adding a styrene monomer to carry out addition polymerization. And
The resin coating layer is at least one selected from oxide particles, metal particles having a natural oxide film on the surface, and metal particles having an oxide film formed on the surface, and the average particle size is 0.05. Containing 10 to 10 μm of particles in an amount of 0.1 to 10% by volume with respect to the total volume of the resin coating layer, and having a thickness of 30 μm to 10 mm ,
When the metal particles are mixed in the resin coating layer, oxygen atoms present on the surface of the metal particles act on styrene groups in the resin of the resin coating layer to generate styrene monomers, and the resulting defects are styrene monomers. A durable member characterized by being coated with . The resin coating layer contains at least one fiber selected from glass fiber, carbon fiber, and boron fiber in an amount of 20% by mass to 60 % by mass with respect to the total mass of the resin coating layer. The durable member according to claim 1. Fibers contained in the resin coating layer ,
Off Lake like fiber, and, matted fibers dispersed in a nonwoven fabric form,
The durable member according to claim 2, wherein the durable member is at least one selected from the group consisting of:   4. The durable member according to claim 1, further comprising an Al alloy sprayed coating layer as an intermediate layer between the base material and the resin coating layer. 5. An open rack type LNG vaporizer according to seawater, wherein the durable member according to any one of claims 1 to 4 is used.

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