A COMPOSITE PANEL AND A METHOD FOR MANUFACTURING A COMPOSITE PANEL

Abstract

 A sandwich-structured composite panel (1), and a method for manufacturing the composite panel. The composite panel (1) comprises a first face skin (3) of sheet metal, a second face skin (4) of sheet metal, and a core (5) made of thermally insulating material arranged between the first face skin and the second face skin, the first and second face skins being attached to the core. The composite panel (1) further comprises an attachment edge (2) at the edge of the composite panel (1) for attaching the composite panel to another composite panel (1). The attachment edge (2) comprises an attachment profile (6) being formed from the sheet metal of at least one of said skins (3, 4) and shaped for a tongue- and-groove attachment. The sandwich-structured composite panel (1) further comprises a protective layer (7) of hydrophobic material arranged on the outer surface of a portion of the sheet metal in the attachment profile (6).

Description

BACKGROUND

[0001] The invention relates to a sandwich-structured composite panel, comprising a first face skin of sheet metal and a second face skin of sheet metal.

[0002] The invention further relates to a method for manufacturing the composite panel.

[0003] It is known to use steel composite panels in buildings and constructions as a façade cladding panel element, a partition wall panel element, or a ceiling panel element. A phenomenon known as crevice corrosion may be problematic for such steel composite panels. The crevice corrosion may take place in confined areas where water solution can penetrate but it cannot change at the same speed as other areas of the metal surface. For instance, seams and joints between composite panels attached to each other may create said confined areas hospitable for crevice corrosion.

[0004] Especially weathering steels, such as COR-TEN steel, may be very sensitive to crevice corrosion. Said weathering steels are group of steel alloys which were developed to eliminate the need for painting and form a stable rust-like appearance after several years' exposure to weather.

BRIEF DESCRIPTION

[0005] Viewed from a first aspect, there can be provided a sandwich-structured composite panel, comprising

• a first face skin of sheet metal,
• a second face skin of sheet metal, and
• a core made of thermally insulating material arranged between the first face skin and the second face skin, the first and second face skins being attached to the core,
• an attachment edge at the edge of the composite panel for attaching the composite panel to another composite panel,
• the attachment edge comprising
• an attachment profile being formed from the sheet metal of at least one of said skins and shaped for a tongue-and-groove attachment,
• the sandwich-structured composite panel further comprising
• a protective layer of hydrophobic material arranged on the outer surface of a portion of the sheet metal in the attachment profile.

[0006] Thereby the composite panel may provide inhibited or attenuated galvanic contacts or couplings between composite panels attached to each other. Thus, a final panel structure having good resistance against crevice corrosion at composite panel attachment joints may be achieved.

[0007] Viewed from a further aspect, there can be provided a method for manufacturing the composite panel as claimed in any one of the preceding claims, the method comprising, simultaneously or in any order, the steps of:

• providing a sheet metal,
• forming the attachment edge and the attachment profile to the sheet metal, thus providing the first face skin and the second face skin,
• attaching the first face skin and the second face skin to a core made of thermally insulating material,
• providing the protective layer in the attachment profile, and
• leaving at least one of the face skins without said protective layer.

[0008] Thereby a method for manufacturing composite panels providing metallic face skin(s) but still having good resistance against crevice corrosion at composite panel attachment joints in a final structure may be achieved.

[0009] The arrangement and the method are characterised by what is stated in the independent claims. Some other embodiments are characterised by what is stated in the other claims. Inventive embodiments are also disclosed in the specification and drawings of this patent application. The inventive content of the patent application may also be defined in other ways than defined in the following claims. The inventive content may also be formed of several separate inventions, especially if the invention is examined in the light of expressed or implicit sub-tasks or in view of obtained benefits or benefit groups. Some of the definitions contained in the following claims may then be unnecessary in view of the separate inventive ideas. Features of the different embodiments of the invention may, within the scope of the basic inventive idea, be applied to other embodiments.

[0010] In one embodiment, the protective layer is a polymer or polymer composite film. An advantage is that a protective layer that is durable may be achieved.

[0011] In one embodiment, the protective layer is a paint layer. An advantage is that a very thin protective layer may be achieved.

[0012] In one embodiment, the attachment profile comprises a tongue-profile, and wherein the protective layer is arranged on surface of said tongue-profile. An advantage is that the protective layer is easy to arrange on the tongue-profile.

[0013] In one embodiment, the attachment profile comprises a groove-profile, and wherein the protective layer is arranged on surface of said groove-profile. An advantage is that the protective layer is well-protected in the groove-profile against mechanical damages.

[0014] In one embodiment, the attachment edge comprises at least two attachment profiles. An advantage is that a robust attachment of panels may be achieved.

[0015] In one embodiment, a first attachment profile is formed from the first face skin and a second attachment profile is formed from the second face skin. An advantage is that the attachment edge may be provided with two attachment profiles in a simple way.

[0016] In one embodiment, the attachment edge comprises a section of the core between the first and second attachment profiles. An advantage is that thermal insulation property may be extended to the attachment edge.

[0017] In one embodiment, the composite panel comprises attachment edges at opposite edges thereof, such that said attachment edges are counterparts to each other. An advantage is at least two of said panels may be attached to each other.

[0018] In one embodiment, the material of the face skin is of naturally passivating metal. An advantage is that the need for painting or another surface finishing may be eliminated.

[0019] In one embodiment, the core is a board of foamed polyurethane. An advantage is that good thermal insulation properties may be achieved.

[0020] In one embodiment, the core is a polyisocyanurate (PIR) insulation board. An advantage is that good thermal insulation properties with improved flame-retardant properties may be achieved.

[0021] In one embodiment, the core is a mineral wool element. An advantage is that a composite panel having good flame-retardant properties may be achieved.

[0022] In one embodiment, the attachment edge is arranged on the upper or the lower edge of the panel. An advantage is that risk of corrosion in horizontal joints of a panel structure may be reduced.

[0023] In one embodiment, the composite panel comprises an airtight seal component arranged in the groove-profile. An advantage is that transport of air and moisture through the joint of composite panels may be prevented, and thus life-time of the panels extended.

[0024] In one embodiment, the method comprises: arranging a temporary protective layer of hydrophobic material on the surface of the sheet metal, forming the outer faces of the first face skin and the second face skin from the surface of sheet metal comprising the temporary protective layer, and following assembling the composite panel: removing the temporary protective layer on the outer faces of at least one of the skins, but leaving the temporary protective layer on the attachment profile, thus forming the protective layer in the attachment profile. An advantage is that the temporary protective layer that protects the skins during manufacturing of the composite panels is utilized as the protective layer, and thus material costs of the composite panels may be reduced.

[0025] In one embodiment, the method comprises: providing the protective layer in the attachment profile by painting. An advantage is that painting is simple way to provide layers on a substrate.

[0026] In one embodiment, the method comprises: arranging a temporary protective layer on the surface of the sheet metal, forming the outer faces of the first face skin and the second face skin from the surface of sheet metal comprising the temporary protective layer, removing the temporary protective layer from the attachment profile, and providing the protective layer in the attachment profile by painting. An advantage is that the temporary protective layer serves as a masking element for painting, thus a very precise painting may be realized.

BRIEF DESCRIPTION OF FIGURES

[0027] Some embodiments illustrating the present disclosure are described in more detail in the attached drawings, in which

Figure 1 is a schematic side view of a composite panel in partial cross-section, and

Figures 2a - 2d are schematic views of method for manufacturing a composite panel.

[0028] In the figures, some embodiments are shown simplified for the sake of clarity. Similar parts are marked with the same reference numbers in the figures.

DETAILED DESCRIPTION

[0029] Figure 1 is a schematic side view of a composite panel in partial cross-section.

[0030] The composite panel 1 may be e.g. a facade cladding panel element, or a partition wall panel element, or a ceiling panel element.

[0031] The composite panel 1 has a sandwich-structure, comprising a first face skin 3 of sheet metal, a second face skin 4 of sheet metal, and a core 5 made of thermally insulating material arranged between the first face skin and the second face skin. The first and second face skins 3, 4 are attached to the core 5.

[0032] In an embodiment, the material of the face skin 3, 4 is naturally passivating metal, such as weathering steel or COR-TEN steel.

[0033] In an embodiment, the core 5 is a board of foamed polyurethane. In another embodiment, the core 5 is a polyisocyanurate (PIR) insulation board. In still another embodiment, the core 5 is a wool element, such as a mineral wool element.

[0034] An attachment edge 2 is arranged at the edge of the composite panel 1 for attaching the composite panel to another composite panel. According to an aspect of the invention, the attachment edge 2 comprises an attachment profile 6 being formed from the sheet metal of first or second face skin 3, 4, or of both first and second skins. The attachment edge 2 is shaped such that the composite panels may be attached by a tongue-and-groove attachment to each other.

[0035] In an embodiment, the composite panel 1 comprises attachment edges 2 at opposite edges thereof, such that said attachment edges 2 are counterparts to each other.

[0036] The composite panel 1 comprises further a protective layer 7 made of hydrophobic material and arranged on the outer surface of a portion of the sheet metal in the attachment profile 6. In an embodiment, the protective layer 7 is a polymer or polymer composite film, such as polyethylene (e.g. high-density polyethylene HDPE) or polypropylene film. In an embodiment, the protective layer comprises polyethylene terephthalate PET, having good ultraviolet resistance, low water absorption and low electrical conductivity. In an embodiment, the protective layer comprises polyethylene naphthalene PEN, having better ultraviolet resistance, lower water absorption and lower electrical conductivity. In an embodiment, the protective layer comprises polyimide PI, having still better ultraviolet resistance, lower water absorption and lower electrical conductivity. The protective layer 7 comprising polymer film may be a monolayered film or multi-layer film.

[0037] In another embodiment, the protective layer 7 is a paint layer.

[0038] In an embodiment, the attachment profile 6 comprises a tongue-profile 8, and the protective layer 7 is arranged on surface of said tongue-profile. In an embodiment, the attachment profile 6 comprises a groove-profile 9, and the protective layer 7 is arranged on surface of said groove-profile.

[0039] In an embodiment, the attachment edge 2 comprises at least two attachment profiles 6. In an embodiment (e.g. as shown in Figures), the attachment edge 2 comprises two parallel tongue-profiles 8, or two parallel groove-profiles 9. In another embodiment, the attachment edge 2 comprises one tongue-profile and one groove-profile arranged parallel with the tongue-profile. In an embodiment, a first of said attachment profiles 6 may be formed from the first face skin 3, whereas the second attachment profile is formed from the second face skin 4.

[0040] in an embodiment, attachment edge 2 comprises an airtight seal component 10 extending preferably all over the length of the attachment edge 2. The seal component 10 may be attached e.g. in the groove-profile 9, and as the tongue-profile is arranged in said groove-profile, the seal component 10 gets squeezed between the profiles.

[0041] In an embodiment, the attachment edge 2 comprises a section of the core 5 between the first and second attachment profiles 6.

[0042] The attachment edge 2 may be arranged on the upper or the lower edge of the panel. Thus, the attachment edges 2 connected to each other may establish a horizontal seam of a panel structure. However, in some another embodiments, the attachment edge 2 is arranged another way. For example, the attachment edge 2 may be arranged on a side edge of the panel, and thus form a part of a vertical seam of a panel structure.

[0043] In Figure 1, attachment means 12 attaching the composite panels 1 to a support structure 13 are screws. In another embodiments, another type of attachment means may be used. In some embodiments, for instance, the composite panel is glued to the support structure.

[0044] The support structure 13 may be basically any structure of a building or a construction being suitable for the attachment of the composite panels.

[0045] Figures 2a - 2d are schematic views of method for manufacturing a composite panel. In the embodiment of the method shown in the Figures, it is first provided 100 a sheet metal 14. As shown in Figure 2a, the sheet metal is provided from a roll of metal sheet 15. However, the sheet metal may also be provided in plate-form.

[0046] A temporary protective layer 11 of hydrophobic material is arranged 101 on the surface of the sheet metal 14.

[0047] Figure 2b is showing forming 102 the attachment edges 2 and the attachment profile 6 to the sheet metal 14, thus providing the first face skin and the second face skin. The temporary protective layer 11 lies on outer faces of the first face skin and the second face skin. The forming 102 may be realized e.g. by roll-forming or cold forming methods.

[0048] Figure 2b is showing attaching 103 the first face skin 3 and the second face skin to a core made of thermally insulating material, by e.g. gluing. Thus, the composite panel 1 has been assembled, shown in Figure 2c.

[0049] Following assembling the composite panel 1, the temporary protective layer 11 is removed 105 on the outer face of at least one of the skins 3, 4, but it is leaved 106 on the attachment profile 6, thus forming 104 the protective layer 7 in the attachment profile 6. In an embodiment, the temporary protective layer 11 is removed 105 on the outer face of both of the skins 3, 4, but it is leaved 106 on the attachment profile 6. In an embodiment, in the removing step it is first made a cutting or slit on an appropriate line in the temporary protective layer 11, and then the sections to be removed are stripped or pulled away from the outer faces of the skin 3, 4.

[0050] It is to be noted that in Figure 2d, the upper face skin 3 is shown with section of the temporary protective layer 11 to be removed (dashed line), whereas the lower face skin 4 is shown said section already removed.

[0051] In some embodiments (e.g. as the shown embodiment), the protective layer 7 is arranged only to one attachment edge of the composite panel. In some another embodiments, the protective layer 7 is arranged to both or all the attachment edges of the composite panel.

[0052] In another embodiment of the method, the protective layer 7 is provided as a strip of polymer or polymer composite film that is attached to the attachment profile 6.

[0053] In still another embodiment of the method, the protective layer 7 is applied in the attachment profile 6 by painting. In this embodiment, it is possible to utilize the temporary protective layer 11 as a painting masking, i.e. the temporary protective layer 11 is removed on sections of the attachment profile 6 to be painted, and then applying paint on exposed sections of the attachment profile 6.

[0054] The invention is not limited solely to the embodiments described above, but instead many variations are possible within the scope of the inventive concept defined by the claims below. Within the scope of the inventive concept the attributes of different embodiments and applications can be used in conjunction with or replace the attributes of another embodiment or application.

[0055] The drawings and the related description are only intended to illustrate the idea of the invention. The invention may vary in detail within the scope of the inventive idea defined in the following claims.

REFERENCE SYMBOLS

[0056] 

1

composite panel

2

attachment edge

3

first face skin

4

second face skin

5

core

6

attachment profile

7

protective layer

8

tongue-profile

9

groove-profile

10

seal component

11

temporary protective layer

12

attachment means

13

support structure

14

sheet metal

15

roll of metal sheet

100 - 106

method steps

Claims

1. A sandwich-structured composite panel (1), comprising

- a first face skin (3) of sheet metal,

- a second face skin (4) of sheet metal, and

- a core (5) made of thermally insulating material arranged between the first face skin and the second face skin, the first and second face skins being attached to the core,

- an attachment edge (2) at the edge of the composite panel (1) for attaching the composite panel to another composite panel (1),

- the attachment edge (2) comprising

- an attachment profile (6) being formed from the sheet metal of at least one of said skins (3, 4) and shaped for a tongue-and-groove attachment,

- the sandwich-structured composite panel (1) further comprising

- a protective layer (7) of hydrophobic material arranged on the outer surface of a portion of the sheet metal in the attachment profile (6).

2. The composite panel as claimed in claim 1, wherein the protective layer (7) is a polymer or polymer composite film.

3. The composite panel as claimed in claim 1, wherein the protective layer (7) is a paint layer.

4. The composite panel as claimed in any of the preceding claims, wherein the attachment profile (6) comprises a tongue-profile (8), and wherein the protective layer (7) is arranged on surface of said tongue-profile.

5. The composite panel as claimed in any of the preceding claims, wherein the attachment profile (6) comprises a groove-profile (9), and wherein the protective layer (7) is arranged on surface of said groove-profile.

6. The composite panel as claimed in any of the preceding claims, wherein the attachment edge (2) comprises at least two attachment profiles (6).

7. The composite panel as claimed in claim 6, wherein a first attachment profile (6) is formed from the first face skin (3) and a second attachment profile (6) is formed from the second face skin (4).

8. The composite panel as claimed in claim 7, wherein the attachment edge (2) comprises a section of the core (5) between the first and second attachment profiles (6).

9. The composite panel as claimed in any of the preceding claims, comprising attachment edges (2) at opposite edges thereof, such that said attachment edges (2) are counterparts to each other.

10. The composite panel as claimed in any of the preceding claims, wherein the material of the face skin (3, 4) is of naturally passivating metal.

11. The composite panel as claimed in any one of the claims 5 - 10, comprising an airtight seal component (10) arranged in the groove-profile (9).

12. A method for manufacturing the composite panel as claimed in any one of the preceding claims, the method comprising, simultaneously or in any order, the steps of:

- providing (100) a sheet metal (14),

- forming (102) the attachment edge (2) and the attachment profile (6) to the sheet metal (14), thus providing the first face skin (3) and the second face skin (4),

- attaching (103) the first face skin (3) and the second face skin (4) to a core (5) made of thermally insulating material,

- providing (104) the protective layer (7) in the attachment profile (6), and

- leaving (105) at least one of the face skins (3, 4) without said protective layer (7).

13. The method as claimed in claim 12, comprising:

- arranging (101) a temporary protective layer (11) of hydrophobic material on the surface of the sheet metal (14),

- forming the outer faces of the first face skin (3) and the second face skin (4) from the surface of sheet metal (14) comprising the temporary protective layer (11), and

- following assembling the composite panel (1):

- removing (105) the temporary protective layer (11) on at least one of the outer faces of the skins, but

- leaving (106) the temporary protective layer (11) on the attachment profile (6), thus forming the protective layer (7) in the attachment profile (6).

14. The method as claimed in claim 12, comprising:

- providing (104) the protective layer (7) in the attachment profile (6) by painting.

15. The method as claimed in claim 14, comprising:

- arranging (100) a temporary protective layer (11) on the surface of the sheet metal (14),

- forming the outer faces of the first face skin (3) and the second face skin (4) from the surface of sheet metal (14) comprising the temporary protective layer (11),

- removing the temporary protective layer (11) from the attachment profile (6), and

- providing (104) the protective layer (7) in the attachment profile (6) by painting.

Drawing