Profiles
11713575 · 2023-08-01
Assignee
Inventors
Cpc classification
E04C2003/0434
FIXED CONSTRUCTIONS
E04B2/60
FIXED CONSTRUCTIONS
E04C3/07
FIXED CONSTRUCTIONS
International classification
B21H8/00
PERFORMING OPERATIONS; TRANSPORTING
E04B2/60
FIXED CONSTRUCTIONS
E04B2/74
FIXED CONSTRUCTIONS
E04B2/78
FIXED CONSTRUCTIONS
Abstract
An elongate profile having a first portion and a second portion, the first and second portions being joined together at a first joining portion, the first and second portions being non collinear, the joining portion comprising an array of raised or rebated formations, each formation extending across the joining portion in a direction which is non-parallel to the principal axis of the profile and flat lands being provided between successive formations in an array and the pitch between successive formations in an array being from 2 to 20 times, for example from 5 to 15 times, the thickness of the flatlands.
Claims
1. A pair of rolls for forming a pattern on sheet material, the first roll comprising a first forming portion for forming at least part of a first pattern on a sheet material and a second forming portion for forming at least part of a second pattern on the sheet material, the first forming portion comprising a first array of projections and the second forming portion comprising a second array of projections, the second roll comprising a third forming portion for forming at least part of said first pattern on the sheet material and a fourth forming portion for forming at least part of said second pattern on the sheet material, the third forming portion comprising a third array of projections and the fourth forming portion comprising an array of rebates, the second forming portion and the fourth forming portion being co-operable to emboss a pattern corresponding to the respective array of projections and rebates on the sheet material and the first and third forming portions are co-operable to cold work harden the sheet material to form an array of projections and depressions with each projection on one side of the sheet material corresponding to a depression on the other side of the sheet material wherein the third and fourth forming portions have distinct shapes, such that, in use, the first pattern and the second pattern formed on the sheet material are distinct, and wherein one or both of the first roll and the second roll are formed in one piece as a unitary article.
2. A pair of rolls according to claim 1, wherein the rolls are mounted for contra rotation.
3. A pair of rolls according to claim 1, wherein the first and second forming portions have distinct shapes, such that, in use, the first pattern and the second pattern formed on the sheet material are distinct.
4. A pair of rolls according to claim 1, wherein each of the first and second forming portions are configured to form the respective pattern along a forming direction, wherein the second forming portion is adjacent, abutting or spaced from the first forming portion in a direction orthogonal to the forming direction.
5. A pair of rolls according to claim 1, wherein the first forming portion includes an interruption in which the second forming portion is located or situated.
6. A pair of rolls according to claim 1, wherein the first roll comprises two first forming portions between which the second forming portion is located and/or the second roll comprises two third forming portions between which the fourth forming portion is located.
7. A pair of rolls according to claim 1, wherein the second forming portion extends around the circumference of the first roll and in the circumferential direction of the first roll and is surrounded or confined or bound by the first forming portion or portions in an axial direction or a direction along the axis of rotation of the rolls.
8. A pair of rolls according to claim 1, wherein the first roll comprises a series of parts or segments, each with a respective first or second forming portion, for example such that the first roll comprises alternating first and second forming portions, and/or wherein the second roll comprises a series of parts or segments each with a respective third or fourth forming portion.
9. A pair of rolls according to claim 1, wherein the first forming portion comprises a surface from which upstands plural male forming members for forming said first pattern.
10. A pair of rolls according to claim 9, wherein the second portion comprises a surface from which the second array of projections upstands.
11. A pair of rolls according to claim 1, wherein each of the first roll and the second roll has a first end and a second end and each of the first roll and the second roll has a gear located at or toward the first end and wherein the second end of each of the first roll and the second roll is free of a gear; in use, the gear of the first roll and the gear of the second roll intermesh to allow the first roll and the second roll to be driven.
12. A pair of rolls according to claim 1, wherein one of the first and second rolls comprises a peripheral extension portion and the other of the first and second rolls comprises a peripheral rebate portion and wherein, in use, the peripheral extension portion extends into and travels in the peripheral rebate portion.
13. A pair of rolls according to claim 1, wherein each of the first and second roll comprise an aperture for receiving a shaft.
14. A method of treating sheet material, the method comprising passing a sheet material between a cooperating pair of rolls as in claim 1, each roll of the pair of rolls having a first portion for embossing the sheet material in a first region and a second portion for shaping the sheet material in a second region, and embossing the sheet material in the first region whilst simultaneously cold work hardening the sheet material in the second region.
15. A method according to claim 14, further comprising providing on the first and second rolls in the respective second portions plural male forming members.
16. A channel section having a base portion and a first side portion and a second side portion, the base portion being joined to the first side portion at a first joining portion, the base portion being joined to the second side portion at a second joining portion, the base portion being non collinear and non coplanar with respect to the first and second side portions, the first side portion being parallel to the second side portion, and the first and second joining portions and each comprising an array of embossed raised projections that extend outwardly, the channel section formed by a pair of rolls for forming a pattern on sheet material, the first roll comprising a first forming portion for forming at least part of a first pattern on a sheet material and a second forming portion for forming at least part of a second pattern on the sheet material, the first forming portion comprising a first array of projections and the second forming portion comprising a second array of projections, the second roll comprising a third forming portion for forming at least part of said first pattern on the sheet material and a fourth forming portion for forming at least part of said second pattern on the sheet material, the third forming portion comprising a third array of projections and the fourth forming portion comprising an array of rebates, the second forming portion and the fourth forming portion being co-operable to emboss a pattern corresponding to the respective array of projections and rebates on the sheet material and the first and third forming portions are co-operable to cold work harden the sheet material to form an array of projections and depressions with each projection on one side of the sheet material corresponding to a depression on the other side of the sheet material, wherein the first and second forming portions have distinct shapes, wherein one or both of the first roll and the second roll are formed in one piece as a unitary article, and wherein the third and fourth forming portions have distinct shapes.
17. A channel section according to claim 16, formed as a C member or section, having an in-turned ledge or flange extending from a distal portion of each of the first and second side portions to overlie the base portion.
18. A channel section according to claim 16, further comprising a first flange portion and a second flange portion, the first flange portion being joined to the first side portion at a third joining portion and the second flange portion being joined to the second side portion at a fourth joining portion, the first and second side portions being non colinear and non coplanar with the first and second flange portions, the first and second flange portions being in-turned, and parallel to and overlying the base portion and at different distances from the base portion.
19. A channel section according to claim 18, wherein the third and fourth joining portions and each comprise an array of embossed raised projections that extend outwardly.
20. A channel section according claim 16, wherein the base portion or the first side portion or the second side portion have a longitudinal strengthening rib.
21. A pair of rolls for forming a pattern on sheet material, the first roll comprising a first forming portion for forming at least part of a first pattern on a sheet material and a second forming portion for forming at least part of a second pattern on the sheet material, the first forming portion comprising a first array of projections and the second forming portion comprising a second array of projections, the second roll comprising a third forming portion for forming at least part of said first pattern on the sheet material and a fourth forming portion for forming at least part of said second pattern on the sheet material, the third forming portion comprising a third array of projections and the fourth forming portion comprising an array of rebates, the second forming portion and the fourth forming portion being co-operable to emboss a pattern corresponding to the respective array of projections and rebates on the sheet material and the first and third forming portions are co-operable to cold work harden the sheet material to form an array of projections and depressions on both sides of the sheet material with each projection on one side of the sheet material corresponding to a depression on the other side of the sheet material, wherein each of the first roll and the second roll are formed in one piece as a unitary article.
22. A pair of rolls for forming a pattern on sheet material, the first roll comprising a first forming portion for forming at least part of a first pattern on a sheet material and a second forming portion for forming at least part of a second pattern on the sheet material, the first forming portion comprising a first array of projections and the second forming portion comprising a second array of projections, the second roll comprising a third forming portion for forming at least part of said first pattern on the sheet material and a fourth forming portion for forming at least part of said second pattern on the sheet material, the third forming portion comprising a third array of projections and the fourth forming portion comprising an array of rebates, the second forming portion and the fourth forming portion being co-operable to emboss a pattern corresponding to the respective array of projections and rebates on the sheet material and the first and third forming portions are co-operable to cold work harden the sheet material to form an array of projections and depressions with each projection on one side of the sheet material corresponding to a depression on the other side of the sheet material, wherein the first and second forming portions have distinct shapes, wherein one or both of the first roll and the second roll are formed in one piece as a unitary article, and wherein the third and fourth forming portions have distinct shapes.
Description
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
(1) In order that the invention may be more fully understood it will now be described, by way of example only and with reference to the accompanying drawings, in which:
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
(24) Referring to
(25) The base portion 2 has a neutral plane, designated P in the drawings. The base portion 2 comprises a central region 20 and a pair of outboard regions 21. Between the central region 20 and each outbound region 21 is a rebated portion 22 to provide, when looking along the profile (see
(26) The side portions 3, 4 each have an elongate inwardly directed rib 30, 40 respectively extending along the length thereof.
(27) The first side portion 3 is of greater area, i.e. it extends further from the base portion 2 in a direction orthogonal to the neutral plane P (and to the direction of the principal axis A of the profile 1), than does the second side portion 4. Also the rib 30 of the first side portion 3 is smaller than the rib 40 of the second side portion 4. The apex 31 of the rib 30 is positioned the same distance from the base portion 2 than is the apex 41 of the other rib 40. The reason for the differences will become apparent. It is also within the scope that the ribs are position at slightly different positions with respect to the neutral plane P and/or with respect to one another.
(28) As a consequence of the different extensions of side portions 3, 4 from the base portion 1, the respective ledge portions 5, 6 are parallel to each other (and to the neutral plane P) but are located at different distances (in a direction orthogonal to the neutral plane P) from the base portion 2.
(29) At each position where a portion 2, 3, 4, 5, 6 joins to another portion (2, 3, 4, 5, 6) there is a joining portion JP1, JP2, JP3, JP4. The material in the region of each joining portion JP1-4 may be, overall thinner than in the adjacent portions 2-6. In the above and below description a ‘joining portion’ is intended to mean a part which joins two elements of a profile the planes of which elements describe an angle therebetween of, or greater than, 30° (in the embodiment of
(30) Located as a longitudinal array 10 along each joining portion JP1-4 is a series of formations, namely outwardly extending protuberances or projections, 10a-d respectively. As is best seen in
(31) As shown each of the projections 10e extends outwardly from the surface of each of the joining portions JP1-4 (i.e. the projections 10 radiate or extend away from one another) and is curved around the respective bend in the profile 1 (that is at the respective joining portion JP1-4) such that each projection 10e is substantially L-shaped. Between successive projections are flat lands FL. It will be appreciated that each of the central region 20 and rebated portions 22 and outboard regions 21 are non-collinear or non-coplanar. It is within the scope of this invention, that a profile 1 comprising ‘joins’ and/or ‘joining portions’ wherein one, some, both or all the joins and/or joining portions comprise one or more embossed projections will fail within the scope of the invention.
(32) The surface of one or more of the portions 2, 3, 4, 5, 6 may be work hardened, embossed or knurled. It is preferred that at least one, some and most preferably all of the surface of the portions 2, 3, 4, 5, 6 are cold rolled and work-hardened, for example using a method set out in one of our patent applications GB2450765A, EP0801234A.
(33) For the avoidance of doubt and as would be appreciated by the skilled person, the term ‘cold working’ (also known as ‘cold work hardening’) as used herein refers to the deformation of metal plastically at a temperature below its lowest recrystallisation temperature, where strain hardening occurs as a result of such permanent deformation. In addition, the term ‘embossing’ as used herein refers to the operation of raising a design or form above and/or below the surface of a component by means of high pressure effected by pressing or squeezing action, and includes debossing.
(34) It is known that embossing and cold work hardening are distinct techniques. Embossing involves compressing material, in this case sheet metal, between two tools (e.g. rolls) to reduce its thickness beyond its ultimate tensile strength into the purely plastic range; it is a compression process which uses significant force to squeeze the material between two tools (e.g. rolls), one of which has a projection or rebate) and the other has a rebate (or projection) whereby the pattern on the tool (e.g. roll) is transferred to the material. In contrast, work hardening by cold roll forming involves plastic strain hardening a material by locally stretching the material without compression. It is conveniently achieved in our above-identified patent applications by using pairs of matched male forming rolls with the teeth of one of the rolls extending (as the rolls rotate) into gaps between teeth on the other roll. Clearly, the skilled person knows and recognises that the techniques are distinct and generate different effects. For example, because of the thinning that occurs with embossing processes embossing is not usually used to work harden or strengthen a sheet material. Other surface effecting process include knurling and coining. Knurling involves pressing a series of sharp serrations on a hardened steel roller into a work-piece, effectively displacing the material sideways using serrations or projections, rather than pushing projections through the other side of the sheet. This has the effect of roughening the surface, for example to increase surface roughness/friction coefficient, but does not materially alter the strength or stiffness of the work-piece (in some cases it may weaken the material).
(35) Because one side portion 3 extends further away from the portion 2 than the other side portion 4 easy and convenient to make a box section, as will be described below.
(36) Referring now to
(37) The profile 1′ has a base portion 2′ from which extend a pair of parallel side portions 3′, The side portions 3′, 4′ respectively terminate with in-turned ledge portions 5′, 6′ which overlie the base portion 2′.
(38) The base portion 2′ has a neutral plane designated P′ in the drawings. The base portion 2′ comprises a central region 20′ and a par of outboard regions 21′. Between the central region 20′ and each outbound region 21′ is a rebated portion 22′ to provide when looking along the profile 1′ (see
(39) The side portions 3′, 4′ each have an elongate inwardly directed rib 30′, 40′ respectively extending along the length thereof.
(40) The first side portion 3′ is of greater area, i.e. it extends further from the base portion 2′ in a direction orthogonal to the neutral plane P′ (and to the direction of the principal axis A′ of the profile 1′), than does the second side portion 4′. Also the rib 30′ of the first side portion 3′ is smaller than the rib 40′ of the second side portion 4′. The apex 31′ of the rib 30′ is positioned slightly further away from the base portion 2′ than is the apex 41′ of the other rib 40′. The reason for the differences will become apparent.
(41) As a consequence of the different extensions of side portions 3′, 4′ from the base portion 1′, the respective ledge portions 5′, 6′ are parallel but are located at different distances (in a direction orthogonal to the neutral plane P′) from the base portion 2′.
(42) At each position where a portion 2′, 3′, 4′, 5′, 6′ joins to another portion (2′, 3′, 4′, 5′, 6′) there is a joining portion JP1′, JP2′, JP3′, JP4′. The material in the region of each joining portion JP1′-4′ may be overall, thinner than in the adjacent portions 2′-6′.
(43) Located as a longitudinal array 10′ along each joining portion JP1′-4′ is a series of inwardly extending protuberances or projections 10a′-d′ respectively. As is best seen in
(44) As shown, the projections 10e′ extend inwardly from the surface of each of the joining portions JP1′-4′ and are curved around the bends in the profile 1′ (that is at the respective joining portion JP1′-4′) such that each projection 10e′ is substantially L shaped. Between successive projections are flat lands FL′.
(45) As well as projections 10e′ in the joining portions JP1′-4′, there is also an array projections 10e′ along each of joins J1′-4′ between each of the central region 20′ and rebated portion 22′ and between each outboard region 21′ and its adjacent rebated portion 22′. It will be appreciated that each of the central region 20′ and rebated portion 22′ and outboard region 21′ and rebated portion 22′ are non-collinear or non-coplanar. It is within the scope of this invention, that a profile comprising ‘joins’ and/or ‘joining portions’ wherein both or either the joins and/or joining portions comprise one or more embossed projections will fall within the scope of the invention.
(46) As well as having the embossed rebates 10′, substantially the entire surface of the side portions 3′ and 4′ has been knurled KP, to provide surface roughening effect on the outermost surface of each side portion 3′, 4′. Alternatively, the or any of the portions 2, 3, 4, 5, 6 could, preferably, have been work hardened in accordance with our above-identified patent applications.
(47) Whilst in
(48) Referring to the profile of
(49) The sheet material 100 is first passed through a pair of embossing rollers 200 comprising a first roll 180 and a second roll 190 contra rotating about respective axes 201, 202. The embossing roller pair 200 causes the sheet material 100 to become embossed to provide an embossed sheet material 101, which may be subsequently shaped to form a profile 1 of the invention.
(50) Passage of the embossed sheet material 101 through successive pairs of rollers 220, 230, 240 causes the castellations (20, 21) on the base portion 2, elongate ribs 30, 40 and folds the side portions 3, 4, and ledge portions 5, 6.
(51) As can be seen the rollers 220, 230, 240 successively bend the sheet material 101 in the region of the joining portions JP1-4 to form the embossed projections into L-shaped projections 10e.
(52) Whilst the above description describes the manufacture of a profile 1 with plain surfaces 2, 3, 4 it is possible to provide a profile with one or more knurled portions (as per the profile 1′ shown in
(53) If it is desired to provide a profile having work hardened portions, for example work hardened in accordance with one of the methods disposed in one of GB2450765A or EP0891234A, it is possible to work harden the sheet material upstream or downstream of the embossing roll pair 200. However, we prefer, for reasons of efficiency, to emboss and work harden the sheet material 100 simultaneously.
(54) Reference is made to
(55) Passage of the sheet material 100 between the matched rolls 180a, 190a causes the projections 191a to emboss the sheet material 100 by stretching and forcing sheet material into the rebates 181a on the upper roll 180a, thereby forming a flat sheet material 101a having plural columns of embossed projections 110a, one column corresponding to each circumferential series of rebates 181a on the first roll 180a and corresponding series of projections 191a on the second roll 190a.
(56) Out board of the embossing regions 181a, 191a, each roll 180a, 190a carries a series of male forming elements in respective work-hardening regions 182a, 192a. The male formers on one roll intermesh with those of the other roll such that as the rolls 180a, 190a contra-rotate the male formers of one roll extend into spaces between the male formers on the other roll and vice versa. The work hardening may be undertaken in accordance with one or more methods described in our earlier patent applications, GB2450765A or EP0891234A, and preferably in accordance with EP2091674.
(57) In order to help with the alignment of the rolls 180a, 190a, one roll (e.g. 180a) may be provided with peripheral extension portions (e.g. as indicated at 183a) which are able to travel in peripheral matched rebate portions (e.g. as indicated at 193a) on the other roll (e.g. 190a).
(58) The sheet material may be formed into a C-profile, for example as shown in relation to
(59)
(60) Referring first to
(61) Referring now to
(62) The embossed region 181b comprises a band having a surface 183b which is raised with respect to the root 185b of the roll 181b (i.e. the surface 183b is radially further from the centre of the roll 180b than the root 185b). Extending into the surface 183b are a series of rebates 184b, each being rectangular with parallel sides extending in the transverse direction T′ and with rounded ends.
(63) Referring now to
(64) The embossed region 191b comprises a band having a surface 193b which is raised with respect to the root 195b of the roll 190b (i.e. the surface 193b is radially further from the centre of the roll 190b than the root 195b). Extending from the surface 193b are a series of projections 194b, each being rectangular with parallel sides extending in the transverse direction T′ and with rounded ends.
(65) In use, the rolls 180b, 190b are aligned such that the male formers 186b of the first roll 180b intermesh with male formers 196b of the second roll 190b and the projections 194b of the second roll at least partially extend into the rebates 184b of the first roll 180b.
(66) When sheet material is passed between the roils 180b, 190b the sheet material is embossed between the cooperating embossing regions 181b, 191b and work hardened in the cooperating work hardening regions 182b, 192b. In the embossing regions, the sheet material is gripped between the facing surfaces 183b, 193b and stretched in the region of the projections 194b and rebates 184b to assume the shape of the projections 194b. In each of the work hardening regions the sheet material does not contact the root 185b, 195b of either roll 180b, 190b but is locally stretched to work harden the material by action of the intermeshing male members 182b, 192b), that is to say there is no compression of the sheet material between a projection 182b (or 192b) on one roll 160b (or 190b) and the root 195b (or 185b) of the other roll 190b (or 180b). In other words, when the tools intermesh there is a clearance between the peaks of the projections (e.g. 182b) on one roll (e.g. 180b) and the root (e.g. 195b) on the other roll (e.g. 190b) which is equal to, or preferably greater than the base gauge of the sheet material to be processed. In contrast, in the embossing regions, there is no such clearance. It is by virtue of the respective configurations (i.e. that the surface 183b of the band is raised with respect to the root 185b, and that the surface 193b of the band is raised with respect to the root 195b) that embossing is effected in that region and that because there is adequate clearance between the facing rollers in the cold work hardening regions that the sheet material is work hardened in those regions.
(67) It is hugely advantageous to be able to conduct each of the distinct forming methodologies in a single pass though one set rollers 180, 190.
(68) The profile 1, for example where one or more of the base 2, side portions 3, 4, ledge portions 5, 6 are work hardened, and formed in accordance with the invention, as better compression characteristics than those absent the array of projections 10a-d.
(69) This is surprising because the profile has not beery work hardened in the joining portions but rather has been embossed, which leads to thinning. It is the joining portions which are required to withstand deflecting forces. Consequently, one would expect a deterioration in the compression characteristics, as compared to a profile which had been work hardened or which had not been processed (embossed) at all.
(70) Referring to
(71) The array of projections and each projection 60 has one or more of a pitch P, a width W, a form depth F and a form position FP.
(72) The pitch P is the inter projection (formation) distance. For a sheet material with a gauge G we prefer a pitch P which can be 2 to 20 times the base gauge G and is preferably from 5 to 15 times the base gauge G of the material. Preferably the pitch P is from 6 to 14 times the base gauge G, and most preferably from 8 to 12 times the base gauge G.
(73) The width W of each projection 60 is determined as the linear distance between the intersection of a line denoting a tangent α of the apex of the top surface 60t of the projection 60 and lines formed between the start of the root part (e.g. 193b in
(74) The form depth F is the distance between a first face 60f of the sheet material and the top surface 60t (or a tangent α of the apex of the top surface 60t where the top surface 60t is not flat, as shown) of a projection 60. In some embodiments the form depth F of is between 1.5 and 4 times the base gauge G of the material, preferably between 1.6 and 3.5 times the base gauge G and most preferably from 1.8 to 3 times the base gauge G.
(75) The form position FP is defined as the linear distance between the end of the curved part of a projection 60 on a joining portion JP1″ (or JP2″) and the end of the curved part of the profile 50. In some embodiments the form position FP of a projection may be from 0.2 G to G, preferably from 0.25 G to 0.75 G and most preferably from 0.4 G to 0.6 G.
(76) In the region of the joining portion JP1″ (or JP2″) the projection 60 may be curved. Such a curved projection 60 may have an internal radius of curvature IR and an external radius of curvature OR. In some embodiments the internal radius of curvature IR of a projection may be from 0.2 G to G, preferably from 0.25 G to 0.75 G and most preferably from 0.4 G to 0.6 G. The external radius of curvature may be IR+G.
(77) Because of the nature of the embossment, the sheet material stretched when forming the projections 10. The resultant thickness RT (for example as measured in the direction of the line XX-XX in
(78) The characteristics described above in relation to
(79) In
(80) In order to demonstrate the increase in compression resistance a series of tests were carried out, as follows.
EXAMPLE 1
(81) In order to test the stiffness single portion of the profile 1 of the invention, one of the wall portions 3 or 4 of a profile according to the invention was loaded and the deflection measured. The profile had the following characteristics, width 63 mm, wall height 32 and 34 mm. The base gauge G was 0.5 mm the projections had a pitch P of 5 mm, and each was 7 mm long, and had a width W of 2.5 mm, a form depth F of 1 mm and RT was 0.4 mm.
(82) The test enabled the stiffness to be calculated. We call this a Single Leg Test.
COMPARATIVE EXAMPLE 1
(83) A profile of identical size and length but absent the projections 10 of the invention was tested an identical manner.
(84) The results are shown in Table 1.
(85) TABLE-US-00001 TABLE 1 Single Leg Test data for Example 1 and Comparative Example 1 Deflection (mm) Deflection (mm) Stiffness Variation at 50N at 150N (N/mm) (%) Ex. 1 0.667 1.967 38.5 (1) C. Ex. 1 0.52 1.8107 38.7 —
(86) The data in Table 1 demonstrates that the stiffness of the profile 1 of the invention is practically identical to that of a profile of the prior art. This is a surprising result because the thinning of the material brought about as a result of the embossing would lead one to expect that the stiffness would be reduced in a profile 1 of the invention.
EXAMPLE 2
(87) In order to test the stiffness of both wall portions of the profile 1 of the invention, both of the wall portions 3 or 4 of a sample identical to that described in Example 1 were loaded and the deflection measured, we call this a Double Leg Test. This enabled the stiffness to be calculated.
COMPARATIVE EXAMPLE 2
(88) A profile of identical size and length but absent the projections 10 of the invention was tested in an identical manner.
(89) The results are shown in Table 2.
(90) TABLE-US-00002 TABLE 2 Double Leg Test data for Example 2 and Comparative Example 2 Deflection (mm) Deflection (mm) Stiffness Variation at 50N at 100N (N/mm) (%) Ex. 2 2.255 4.83 19.4 6 C. Ex. 2 2.32 5.06 18.2 —
(91) The data of Table 2 demonstrates that the deflection profile and stiffness of the profile 1 of the invention is substantially greater than that of a profile of the prior art. These are surprising results, not least because of the apparent identically under the Single Leg Test and because of the change of the material brought about as a result of the embossing would suggest that the stiffness would be reduced in a profile 1 of the invention. We believe that this shows a significant improvement over the prior art.
EXAMPLE 3
(92) We conducted some comparative tests on a sample of stud 1 having ‘external’ projections 10 according to
(93) Both studs 1, 1′ had the same number and array of projections 10, 10′ (that being the array shown in
(94) The moment of inertia and sectional modulus of each of the studs 1, 1′ was determined.
COMPARATIVE EXAMPLE 3
(95) A profile of identical size and shape but absent the projections was tested in an identical manner.
(96) The results are shown in Table 3.
(97) TABLE-US-00003 TABLE 3 Data showing the moment of inertia (I) and sectional modulus (Z). I.sub.XX (mm.sup.4) I.sub.YY (mm.sup.4) Z.sub.XX (mm.sup.3) Z.sub.YY (mm.sup.3) Ex. 3A 60500 10700 1650 420 Ex. 3B 58200 10100 1700 450 C. Ex. 3 58200 9700 1650 410
(98) It can clearly be seen that the moment of inertia I (indicative of the resistance to bending) is higher in both of the examples of the invention by between 4 and 10% and the sectional modulus from 2.5 to 7% (both in the y direction).
(99) Both these results show that a profile made in accordance with the invention is stiffer than a profile made in accordance with the prior art.
(100) To further test the performance of profiles of the invention, we conducted some further tests.
EXAMPLE 4
(101) We conducted a series of three point bend tests on plural samples of profiles made according to the invention and formed in accordance with
COMPARATIVE EXAMPLE 4
(102) A pair of profiles of the same dimensions but absent the projections were tested in the same manner as set out in Example 4.
(103) The results (average of 3 runs in each case) are shown in Table 4.
(104) TABLE-US-00004 TABLE 4 Three Point Bend Test data for Example 4 and Comparative Example 4 Maximum load Maximum Force @ Force @ (N) Extension (mm) 3 mm (N) 5 mm (N) Ex. 4 1338 17 245 430 C. Ex. 4 848 12 226 383
(105) The results clearly demonstrate that the profile of the invention preformed better in terms of its ability to withstand defecting forces time a profile of the prior art.
EXAMPLE 5
(106) We decided to further investigate single leg compression performance by mounting a series of profiles of the invention in a test rig as shown in
COMPARATIVE EXAMPLE 5
(107) We tested a series of prior art profile having the same dimensions as those of Example 5 but absent the projections.
(108) The results (average of four runs in each case are shown in Table 5.
(109) TABLE-US-00005 TABLE 5 Single Leg Test data for Example 5 and Comparative Example 5 Maximum load Maximum Force @ Force @ (N) Extension (mm) 4 mm (N) 8 mm (N) Ex. 5 303 13 156 254 C. Ex. 5 188 14 91 153
(110) These results demonstrate that as the amount of compression increases (that is as against Example 1), the profile of the invention shows better performance over the prior art.
EXAMPLE 6
(111) To investigate the performance of the profile of the invention a series of stud walls were constructed, the walls being either 3.6 m high (Example 6A) or 4.2 m high (Example 6B). Each wall comprised a header and footer track section of 3.6 m length and between which 7 equi-spaced studs formed from profiles according to the invention were located.
(112) For Example 6A a single layer of plasterboard was attached to each side of the so formed frame to form a stud wall 3.6 m high and 3.6 m wide.
(113) For Example 6B a double layer of plasterboard was attached to each side of the so-formed frame to form a stud wall 4.2 m high and 3.6 m wide.
(114) Each wall was subjected to a positive pressure applied uniformly over the surface of the wall, the pressure being increased at 50 N/m.sup.2 increments.
COMPARATIVE EXAMPLE 6
(115) Two identical walls were constructed from prior art profiles which had the same characteristics but were absent the embossed projections of the invention.
(116) The results are shown in Table 6 and indicated graphically in
(117) TABLE-US-00006 TABLE 6 Wall performance data for Example 6 and Comparative Example 6 Def @ 200 N/mm.sup.2 Force @ L/240 Bending Stiffness @ (mm) (N/m.sup.2) L/240 (Nm.sup.2) Ex. 6A 14 205 29944 C. Ex. 6A 16 195 28515 Ex. 6B 11 266 62311 C. Ex 6B 17 202 46918
(118) The data demonstrates that the profile of the invention performs better when constructed as a wall than profiles of the prior art.
(119) Moreover, in a further test it was found that board stepping was significantly reduced in profiles of the invention as compared to profiles of the prior art.
(120) It is also within the scope of the invention to provide an array of projections 10 at each vertex of non-co-linear portions of the profile 1, or any other profile. Moreover, projections 10 may be provided at a single vertex of non-co-linear portions of a profile (or the profile 1) or indeed at plural vertices.
(121) The projections 10 on the profile 1 extend outwardly, which is preferred because, we believe, it leads to improved performance. Some or ail of the projections in the same or different arrays (10a-d) may extend inwardly. Moreover, the embossing may be carried out by use of a forming roll (e.g. roll 180 or 190) which carries formations and a plain roll (e.g. the other of roll 190 or 180) the combined action of both causing formation of the projections 10a-d. The projections may be any shape. We prefer embossed projections with a shape having a principal axis which is not parallel to the principal axis of the profile because this leads to a greater improvement in performance.
(122) We prefer profiles which have been both embossed that is embossed to form said projections 10, and work-hardened. Toots which can perform both operations simultaneously on a sheet material are preferred, in preferred operations and tools, the embossing and embossing regions (and consequential embossments) are bound, in the transverse direction of the work-piece or sheet metal, by work hardening and work hardening regions (and consequential work hardened regions), in the running direction of the tool, the sheet material having corresponding embossments and work hardened zones.
(123) The embossed projections may have a pitch of 3 mm or greater. In some embodiments, in a direction along an array of projections, from 30-70% of the distance is taken up by the width of the projections. The pitch projection in an array on one joining portion a different to the pitch of projections on another joining portion on the same profile.
(124) The profile may be in other shapes. It may provide grid for a suspended ceiling or other framing or sectional members. For example, the profile can be an I, Z, W or other sectional shape, for example a box section or other three dimensional shape, whether regular, irregular or otherwise convoluted. We can provide profiles from steel up to 3 mm thick.