Marine structure and building structure

Abstract

An object of the present disclosure is to provide a marine structure (or a building structure) including a clad steel plate, to which a projection member can be suitably welded.SOLUTION: A marine structure 1 (or a building structure 1) includes a clad steel plate 10 having a base material 11 made of steel and a cladding material 12 covering the base material 11, and includes a projection member 20 welded to the clad steel plate 10 and projecting from the clad steel plate 10.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to marine and architectural structures. [Background technology]

[0002] BACKGROUND ART Titanium clad steel plate covered structures have been known in the past. Patent Document 1 discloses that in a part of the area where a steel structure is covered with a titanium-clad steel plate, an area is created where the titanium-clad steel plate is removed, and a stainless steel protrusion structure is arranged in this area so as to connect to the steel structure. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-5162 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide an offshore structure including clad steel plates, in which protrusion members can be suitably welded. Another object of the present disclosure is to provide an architectural structure that includes clad steel plates and that allows protruding members to be suitably welded. [Means for solving the problem]

[0005] The marine structure according to the present disclosure includes: A marine structure comprising a clad steel plate having a steel base material and a laminated material covering the base material, a protruding member welded to the clad steel plate and protruding from the clad steel plate; It is characterized by: In addition, the architectural structure according to the present disclosure is An architectural structure comprising a clad steel plate having a steel base material and a laminated material covering the base material, a protruding member welded to the clad steel plate and protruding from the clad steel plate; It is characterized by: [Effects of the Invention]

[0006] According to the present disclosure, it is possible to provide an offshore structure including clad steel plates in which protrusion members can be suitably welded. Furthermore, according to the present disclosure, it is possible to provide an architectural structure that includes clad steel plates and in which protruding members can be suitably welded. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic cross-sectional view illustrating a structure according to an embodiment of the present disclosure. [Figure 2] FIG. 1 is a schematic cross-sectional view illustrating a structure according to an embodiment of the present disclosure, the view being related to partial penetration welding. [Figure 3] FIG. 1 is a schematic cross-sectional view illustrating a structure according to an embodiment of the present disclosure, showing full penetration welding. [Figure 4] FIG. 10 is a schematic cross-sectional view for explaining a structure according to an embodiment of the present disclosure, showing an example in which a groove is formed at a base end of a protruding member. [Figure 5] FIG. 1 is a schematic cross-sectional view illustrating a structure according to an embodiment of the present disclosure, showing an enlarged view of the vicinity of a weld bead. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present disclosure will be described using examples, but it is clear that the present disclosure is not limited to the examples described below. In the following description, specific numerical values ​​and materials may be used as examples, but other numerical values ​​and materials may be used as long as the effects of the invention according to the present disclosure are obtained. Furthermore, the components of the following embodiments can be combined with each other. Furthermore, in this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. In this specification, the term "process" includes not only an independent process, but also a process that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved.

[0009] [First embodiment] A structure according to an embodiment of the present disclosure will be described below with reference to the drawings. Fig. 1 shows a schematic cross-sectional view for explaining a structure 1 according to this embodiment. Note that the X, Y, and Z coordinate axes in Figs. 1 to 7 are mutually orthogonal. In the example of Fig. 1, the plate surface of the stainless clad steel plate 10 is parallel to the X and Y coordinate axes.

[0010] (Stainless clad steel plate) The structure 1 according to this embodiment includes a stainless clad steel plate 10. The stainless clad steel plate 10 has a steel base material 11 and a stainless clad material 12 that covers the base material 11. FIG. 1 shows a portion of the stainless clad steel plate 10.

[0011] The base material 11 is a steel plate. The steel plate of the base material 11 is not particularly limited, but is more preferably a steel plate containing the following chemical composition: C: 0.23 mass % or less, P: 0.035 mass % or less, and S: 0.035 mass % or less. The chemical composition of the base material 11 may be determined by referring to a mill sheet that lists the steel type and chemical components. However, instead of using such a method, the steel plate to be used may be specified by a trade name or the like, and it may be determined whether the base material 11 is a steel plate based on the specifications of the steel plate.

[0012] The cladding material 12 is made of stainless steel. The cladding material 12 may be made of, for example, SUS410, SUS430, SUS304, SUS312L, etc. Furthermore, the cladding material 12 may be made of SUS312L from the viewpoint of not losing corrosion resistance even in high temperature environments or high salt concentration environments.

[0013] The thickness of the stainless clad steel plate 10 is not particularly limited, but is preferably 6 mm or more from the viewpoint of strength. Furthermore, the thickness of the base material 11 constituting the stainless clad steel plate 10 is not particularly limited. The thickness of the laminated material 12 constituting the stainless clad steel plate 10 is not particularly limited, but is preferably about 2 mm from the viewpoints of strength and economy.

[0014] The above-mentioned stainless clad steel plate 10 is manufactured by joining a steel plate serving as the base material 11 and a stainless steel plate serving as the clad material 12 by a rolling method, build-up welding method, pressure welding method, explosive welding method, molten metal welding method, welding method, or the like.

[0015] (exposed part) An exposed portion 100 where the base material 11 is exposed is formed on the surface of the stainless clad steel plate 10. The exposed portion 100 is formed on the surface (surface 10a and surface 10b) of the stainless clad steel plate 10 on the side where the clad material 12 is located. In other words, the exposed portion 100 is formed on the surface 10a (surface 12a of the clad material 12).

[0016] The exposed portion 100 has an exposed surface 100s and an exposed end surface 100e. The exposed surface 100s is formed substantially parallel to the surface 10a of the stainless clad steel plate 10. The exposed end surface 100e is formed in a direction intersecting the surface 10a of the stainless clad steel plate 10. It is preferable that the base material 11 is exposed over the entire exposed surface 100s. That is, it is preferable that the exposed portion 100 is formed deeper than the thickness of the laminated material 12. In other words, it is preferable that the exposed surface 100s is located farther from the surface 10a of the stainless clad steel plate 10 in the thickness direction of the stainless clad steel plate 10 than the boundary between the base material 11 and the laminated material 12. The boundary between the base material 11 and the laminated material 12 is the joining surface between the surface 11b of the base material 11 and the surface 12b of the laminated material 12.

[0017] The exposed portion 100 may be formed by cutting a portion of the clad material 12, or the clad material 12 and the base material 11, from the stainless clad steel plate 10. Alternatively, the clad material 12 may not be provided in some areas during the production of the stainless clad steel plate 10, resulting in a stainless clad steel plate 10 having the exposed portion 100.

[0018] The shape of the exposed portion 100 when viewed from the surface (surface 10a) of the stainless clad steel plate 10 is not particularly limited, and it is preferable that the shape encompasses the base end portion 21 of the protruding member 20 described below.

[0019] (Protruding parts) The structure 1 according to this embodiment includes a protruding member 20. The protruding member 20 protrudes from the stainless clad steel plate 10 at the exposed portion 100. That is, the protruding member 20 is arranged so as to extend in a direction intersecting the surface of the stainless clad steel plate 10. The protruding member 20 is welded to the stainless clad steel plate 10 at the base end 21 side of the protruding member 20. The tip end 22 of the protruding member 20 is located on the opposite side to the base end 21. Other members such as accessories as described below may be attached to the tip end 22 side.

[0020] The protruding member 20 is preferably made of stainless steel, stainless clad steel plate, carbon steel or a nickel-based alloy. The stainless steel is not particularly limited, but may be, for example, SUS410, SUS430, SUS304, SUS312L, etc. Furthermore, from the viewpoint of not losing corrosion resistance even in high temperature environments or high salt concentration environments, the stainless steel may be SUS312L. The carbon steel is not particularly limited, but more preferably has a chemical composition containing 0.23 mass% or less, P: 0.035 mass% or less, and S: 0.035 mass% or less. A nickel-based alloy is an alloy whose main component is nickel (nickel content is 50% by mass or more). The chemical composition of the protrusion member 20 may be determined by referring to a mill sheet that lists the steel type and chemical components. However, instead of using such a method, the material to be used may be specified by a trade name or the like, and the material of the protrusion member 20 may be specified based on the specifications of this material.

[0021] It is more preferable that the pitting corrosion index of the protruding member 20 is equal to or greater than the pitting corrosion index of the laminated material 12. In the HAZ (Heat Affected Zone) and weld metal, the welding heat can cause additives such as chromium, which has high corrosion resistance, and iron, which has low corrosion resistance, to become non-uniform, resulting in component segregation and the formation of localized areas with low corrosion resistance. By using a highly corrosion-resistant material for the protruding member 20, welding can be performed so that the pitting corrosion index of the base material 11 is satisfied, even if component segregation occurs. The pitting corrosion index can be calculated using the formula PRE=Cr+3.3Mo+16N or PREW=Cr+3.3(Mo+0.5W)+16N, where Cr, Mo, W, and N represent the contents (mass%) of chromium, molybdenum, tungsten, and nitrogen, respectively. By using a highly corrosion-resistant material for the welding material forming weld bead 30, welding can be performed so as to satisfy the pitting corrosion index of base metal 11 even if there is component segregation.

[0022] There are no particular limitations on the shape of the protruding member 20. The protruding member 20 may have a shape that is suitable for the purpose of the protruding member 20, such as connecting another member to the protruding member 20. For example, the protruding member may be provided with a notch, a hole, a recess, a screw hole, a male thread, or the like.

[0023] Next, a description will be given of welding of the protruding member 20. It is preferable that the base end portion 21 of the protruding member 20 is welded to the base material 11. The strength of the joint is improved by forming the exposed portion 100 and welding the protruding member 20 to the base material 11 rather than by welding the protruding member 20 to the laminated material 12 of the stainless clad steel plate 10. In other words, the strength of the interface between the laminated material 12 and the base material 11 is relatively low, and there is a possibility that the interface will peel off when subjected to a tensile force in the plate thickness direction, so the laminated material 12 is peeled off.

[0024] The welding between the base end 21 of the protruding member 20 and the base material 11 is preferably any one of fillet welding, partial penetration welding, and full penetration welding. For example, Fig. 1 shows an example of a structure 1 in which the protruding member 20 and the base material 11 are joined by fillet welding.

[0025] 2 shows an example of a structure 1 in which a protruding member 20 and a base material 11 are joined by partial penetration welding. In partial penetration welding, a portion of the protruding member 20 and / or the base material 11 melts due to the heat input during welding, and a weld bead 30 extends between the protruding member 20 and the base material 11, with the weld metal of the weld bead 30 occupying part of the space between the protruding member 20 and the base material 11.

[0026] 3 shows an example of a structure 1 in which a protruding member 20 and a base material 11 are joined by full penetration welding. In full penetration welding, a portion of the protruding member 20 and / or the base material 11 melts due to the heat input during welding, and a weld bead 30 extends between the protruding member 20 and the base material 11, with the weld metal of the weld bead 30 occupying the entire space between the protruding member 20 and the base material 11.

[0027] In either of the above welding methods, it is preferable that weld bead 30 be formed between exposed surface 100s of exposed portion 100 and side surface 23 of protruding member 20. Weld bead 30 may be formed to surround base end 21 of protruding member 20. That is, weld bead 30 may be provided continuously around protruding member 20. Alternatively, when overlay welding, which will be described later, is performed, weld bead 30 may be provided partially around base end 21 of protruding member 20. That is, weld bead 30 may be provided discontinuously.

[0028] In the example of FIG. 1, the weld bead 30 has a predetermined length and extends in a direction along the Y coordinate axis.

[0029] Weld bead 30 formed by welding is preferably formed so as to extend beyond the boundary between base material 11 and laminated material 12 to tip 22 of protruding member 20. By forming weld bead 30 so as to extend beyond the boundary between base material 11 and laminated material 12 to tip 22 of protruding member 20, the strength of the joint can be ensured while reliably joining the protruding member and base material.

[0030] The positional relationship between weld bead 30 and the boundary between base material 11 and laminated material 12 is observed as follows: A sample having a cross section perpendicular to the direction in which the weld bead extends is cut out from the structure to be observed, and the sample is visually observed to determine whether weld bead 30 extends beyond the boundary between base material 11 and laminated material 12 toward tip 22 of protruding member 20.

[0031] The weld may be a partial penetration weld or a full penetration weld. In the structure 1 according to the present embodiment, as shown in Fig. 4, it is preferable that a groove 24 is formed at the base end 21 of the protruding member 20. By providing the groove 24, the weld strength of the weld bead 30 with the base material 11 can be ensured.

[0032] In the structure 1 according to this embodiment, buildup welding may be further performed on the weld bead 30 formed by welding to form a buildup weld bead 40. By performing buildup welding to form the weld buildup bead 40, corrosion resistance can be improved.

[0033] The overlay weld bead 40 is in contact with the cladding material 12 and the protruding member 20 and is preferably made of stainless steel or a nickel-based alloy having a pitting corrosion index equivalent to that of the cladding material 12 and the protruding member 20 . When the protruding member 20 is a stainless clad steel plate, the pitting corrosion index of the protruding member 20 is the pitting corrosion index of the stainless steel that is the clad material.

[0034] The leg length of the weld bead 30 is preferably longer than the leg length of the overlay weld bead 40. As shown in Fig. 5 , the leg length of the weld bead 30 is the minimum height Hf of the weld bead 30 in the thickness direction of the stainless clad steel plate 10. The leg length of the overlay weld bead 40 is the minimum height Ho of the weld bead 40 in the thickness direction of the stainless clad steel plate 10. With this configuration, the welding strength of weld bead 30 can be ensured.

[0035] The throat thickness of weld bead 30 is preferably thicker than the throat thickness of overlay weld bead 40. With this configuration, the weld strength of weld bead 30 can be ensured.

[0036] Because it is difficult to measure throat thickness directly, the leg length that will ensure the required throat thickness is determined, and then the leg length is controlled during welding, thereby ultimately ensuring the required throat thickness. Specifically, the required throat thickness is first determined at the design stage, and then the leg length that will ensure the required throat thickness is determined. At this time, the required leg length is recorded on drawings, etc. During welding, the leg length is measured and controlled. The throat thickness can then be calculated from the geometric relationship between the leg length of the weld in the design and the groove depth.

[0037] The leg length or throat thickness of the weld bead 30 and the overlay weld bead 40 can be obtained based on the drawings, manufacturing instructions, etc. at the time of welding.

[0038] The overlay weld bead 40 may be made up of multiple layers. In order for the overlay weld bead 40 to be made up of multiple layers, overlay welding is performed in multiple steps. By performing overlay welding in multiple steps, the chemical components of the base material 11 and the protruding member 20 are prevented from flowing into the overlay weld bead 40. This ensures the corrosion resistance of the overlay weld bead 40. Whether the overlay weld bead 40 is made up of multiple layers can be determined based on welding drawings, manufacturing instructions, etc.

[0039] For example, if a titanium clad steel plate such as that described in Patent Document 1 is applied to the structure according to this embodiment, there is a concern that molten metal will flow into the welded joint from the titanium and base steel plate, making the welded joint more susceptible to embrittlement. However, in the structure according to this embodiment, the protruding members protruding from the stainless clad steel plate are joined to the base material by welding in the exposed portions of the stainless clad steel plate, so there is less concern about embrittlement at the welded joints as described above.

[0040] The structure 1 according to this embodiment is a structure including a stainless clad steel plate, and the protruding members can be suitably welded to the exposed portions where the base material is exposed.

[0041] In the structure 1 according to this embodiment, there is no need to provide any additional members other than the stainless clad steel plate 10 in order to connect the protruding members 20. Therefore, it is possible to reduce manufacturing costs while ensuring sufficient corrosion resistance.

[0042] [Second embodiment] A welding method according to an embodiment of the present disclosure will be described below. The welding method according to this embodiment includes a bending step, a cutting step, and a welding step.

[0043] (Bending process) In the bending process, the stainless clad steel plate is bent. By bending, the stainless clad steel plate is processed into, for example, a steel pipe or a bent plate material. During bending, the surface to which the protruding member is welded is processed so as to be the surface on which the clad material is located.

[0044] (cutting process) In the cutting step, the stainless clad steel plate is cut to form an exposed portion on the surface of the stainless clad steel plate. The cutting step is carried out after the bending step. In the cutting step, the surface of the stainless clad steel plate on which the cladding material is located is cut, thereby removing the cladding material and exposing the base material of the stainless clad steel plate.

[0045] In the cutting step, a part of the base material may be cut off. By cutting off a part of the base material, it is possible to reliably expose the base material without leaving any mating material on the exposed surface.

[0046] (welding process) In the welding step, the protruding member is welded to the base material at the exposed portion. The welding step is performed after the cutting step. In the welding step, the base end of the protruding member is brought into contact with the exposed portion of the base material, and the base end of the protruding member and the base material are joined by welding. The base end of the protruding member and the base material are joined by a weld bead formed by welding. The welding is preferably any one of fillet welding, partial penetration welding, and full penetration welding. The shape of the weld bead formed by welding is as described in the above-mentioned embodiment.

[0047] In the welding step, buildup welding may be further performed after the above welding. That is, buildup welding may be further performed on the weld bead formed by welding to form a buildup weld bead. The shape of the buildup weld bead formed by welding is as described in the above-described embodiment.

[0048] The method may further include a preparation step of preparing a stainless clad steel plate before the bending step.

[0049] The welding method according to this embodiment allows the exposed portion to be formed with high precision. Furthermore, the welding method allows errors that occur in the bending process to be absorbed in the cutting process. Furthermore, the welding method according to this embodiment allows all processes to be carried out, for example, in a factory.

[0050] [Third embodiment] The welding method according to this embodiment includes a bending process, a cutting process, and a welding process. The welding method according to this embodiment differs from the welding method according to the second embodiment in that the bending process is carried out after the cutting process, and then the welding process is carried out. However, since each process of this embodiment is the same as each process of the second embodiment, a description thereof will be omitted here.

[0051] (Variation) In the welding method according to the above embodiment, the protruding member 20 may be welded to the base material 11 in a downward position or a vertical position.

[0052] (Addendum) The structure and welding method according to the above embodiment can be understood, for example, as follows. (1) A structure according to one embodiment of the present disclosure includes: A structure comprising a stainless clad steel plate having a steel base material and a stainless steel clad material covering the base material, An exposed portion where the base material is exposed is formed on the surface of the stainless clad steel plate, The exposed portion is provided with a protruding member protruding from the stainless clad steel plate. It is characterized by: The structure is a structure including a stainless clad steel plate, and the protruding member can be suitably welded to the exposed portion where the base material is exposed.

[0053] (2) In the structure described in (1) above, The base end of the protruding member may be welded to the base material. In the above structure, the base end of the protruding member is welded to the base material, which has the advantage of improving the strength of the joint.

[0054] (3) In the structure described in (2) above, The welding between the base end of the protrusion member and the base material is any one of fillet welding, partial penetration welding, and full penetration welding, The weld bead formed by the welding may be formed so as to extend beyond the boundary between the base material and the clad material toward the tip end of the protruding member. This allows the protruding member and the base material to be reliably joined while ensuring welding strength.

[0055] (4) In the structure described in (2) or (3) above, The weld may be a partial penetration weld or a full penetration weld. In the above structure, the welding strength between the weld bead and the base material can be ensured.

[0056] (5) In the structure according to any one of (2) to (4) above, overlay welding is performed on the weld bead formed by the welding; The overlay weld bead formed by the overlay welding may be in contact with the laminated material and the protruding member, and may be made of stainless steel or a nickel-based alloy having a pitting corrosion index equivalent to the pitting corrosion index of the laminated material and the protruding member. In the above structure, corrosion resistance can be improved by applying build-up welding.

[0057] (6) In the structure described in (5) above, The leg length of the weld bead may be longer than the leg length of the overlay weld bead. In the above structure, the welding strength of the weld bead can be ensured.

[0058] (7) In the structure according to any one of (5) or (6) above, The throat thickness of the weld bead may be greater than the throat thickness of the overlay weld bead. In the above structure, the welding strength of the weld bead can be ensured.

[0059] (8) In the structure according to any one of (5) to (7) above, The overlay weld bead may be made up of a plurality of layers. In the above structure, the inflow of chemical components of the base material and the protruding member into the overlay weld bead is suppressed, thereby ensuring the corrosion resistance of the overlay weld bead.

[0060] (9) In the structure according to any one of (5) to (8) above, The overlay weld bead may be formed so as to extend over the surface of the laminated material. In the above structure, the overlay weld bead can ensure corrosion resistance of the exposed end surfaces of the cladding material and the base material.

[0061] (10) In the structure according to any one of (2) to (9), The weld bead formed by the welding may not be in contact with the mating material. In the above structure, the inflow of chemical components of the weld bead into the laminated material is suppressed.

[0062] (11) In the structure according to any one of (1) to (10) above, The protruding member may be stainless steel, stainless clad steel plate, carbon steel, or a nickel-based alloy. The above structure has the advantage that the material can be appropriately selected depending on the required corrosion resistance.

[0063] (12) In the structure described in (11) above, The pitting corrosion index of the protruding member may be equal to or greater than the pitting corrosion index of the laminated material. In the above structure, by using a highly corrosion-resistant material for the protrusion material, there is an advantage that welding can be performed so as to satisfy the pitting corrosion index of the base material even if there is component segregation.

[0064] (13) In the structure according to any one of (1) to (12) above, The protruding member may be a member for attaching an accessory to the structure. The above structure has the advantage that accessories can be easily attached to the structure, and can be preferably used as a structure to support accessories, such as, but not limited to, breakwaters, ladders, walkways, etc.

[0065] (14) A welding method according to one aspect of the present disclosure includes: A welding method applied to the structure according to any one of (1) to (13) above, a bending process step of bending the stainless clad steel plate; a cutting step, which is carried out after the bending step, of cutting the stainless clad steel plate to form the exposed portion on the surface of the stainless clad steel plate; a welding step of welding the protruding member to the base material at the exposed portion after the cutting step; The present invention is characterized by comprising: The above welding method allows the exposed portion to be formed with high precision, and also allows errors occurring in the bending process to be absorbed in the cutting process.

[0066] (15) A welding method according to one aspect of the present disclosure includes: A welding method applied to the structure according to any one of (1) to (13) above, a cutting step of cutting the stainless clad steel plate to form the exposed portion on the surface of the stainless clad steel plate; a bending process step of bending the stainless clad steel plate, which is carried out after the cutting process; a welding step of welding the protruding member to the base material at the exposed portion after the bending step; The present invention is characterized by comprising: The above welding method allows the exposed portion to be formed with high precision, and also allows errors occurring in the bending process to be absorbed in the cutting process. [Industrial Applicability]

[0067] According to the marine structure or architectural structure of the present disclosure, protruding members can be suitably welded in marine structures or architectural structures equipped with clad steel plates. Therefore, the invention of the present disclosure is extremely useful industrially. [Explanation of symbols]

[0068] 1 structure 10 Stainless clad steel plate 100 exposed area 20 Protruding member 30 Weld Bead 40 Overlay weld bead

Claims

1. A marine structure comprising a clad steel plate having a steel base material and a laminated material covering the base material, a protruding member welded to the clad steel plate and protruding from the clad steel plate; A marine structure characterized by:

2. overlay welding is performed on the weld bead formed by the welding; an overlay weld bead formed by the overlay welding is in contact with the laminated material and the protruding member, and is made of stainless steel or a nickel-based alloy having a pitting corrosion index equivalent to that of the laminated material and the protruding member; 2. The marine structure according to claim 1 .

3. The weld bead formed by the welding is not in contact with the mating material.

2. The marine structure according to claim 1 .

4. The protruding member is a member for attaching an attachment to the marine structure.

2. The marine structure according to claim 1 .

5. An architectural structure comprising a clad steel plate having a steel base material and a laminated material covering the base material, a protruding member welded to the clad steel plate and protruding from the clad steel plate; An architectural structure characterized by:

6. overlay welding is performed on the weld bead formed by the welding; an overlay weld bead formed by the overlay welding is in contact with the laminated material and the protruding member, and is made of stainless steel or a nickel-based alloy having a pitting corrosion index equivalent to that of the laminated material and the protruding member; 6. The architectural structure according to claim 5.

7. The weld bead formed by the welding is not in contact with the mating material.

6. The architectural structure according to claim 5.

8. The protruding member is a member for attaching an accessory to the architectural structure.

6. The architectural structure according to claim 5.

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