GB2228752A

GB2228752A - Metal beam

Info

Publication number: GB2228752A
Application number: GB8902321A
Authority: GB
Inventors: Alan Bell
Original assignee: STEELPRESS
Current assignee: STEELPRESS
Priority date: 1989-02-02
Filing date: 1989-02-02
Publication date: 1990-09-05
Also published as: GB8902321D0

Abstract

A beam such as a roof purlin, roof beam or side rail, or eaves beam or valley beam is formed from commercial quality steel so as to have a web (2) and side flange formations (3, 4) and preferably also edge reinforcing ribs (9, 10). The metal sheet is structurally embossed (E) to strengthen the sheet, and the embossment (E) may comprise an array of separate deformations (11, 12) or a series of continuous deformations or corrugations (13). <IMAGE>

Description

"SUPPORT BEAM MEMBERS" DESCRIPTION: The present invention relates to support beam members made of sheet metal material for use in buildings. These support beam members include purlins and roof beams, and lintel beams, and also eaves beams and valley beams.

The above beam members are formed from metal sheeting, and to provide the necessary structural strength in the member it has been necessary for the sheeting of the member to have a certain minimum thickness and shape.

an many cases this has resulted in the member having the disadvantage of being undesirably heavy. The greater metal usage resulting from the use of thicker sheeting has of course the further disadvantage of increasing the cost of the beam member and the associated main structural frame.

It is an object of the present invention to obviate or mitigate these disadvantages.

According to the present invention a support beam member for a building is formed from sheet metal material and comprises a longitudinally extending main body part with a lateral flange at at least one edge of said main body part, said sheet material being structurally embossed so as to strengthen the material.

Preferably the structurally embossed sheet material has strength properties at least five per cent greater than a corresponding non-embossed plan sheet of a thickness equivalent to the material before it is structurally embossed.

Preferably the sheet material of the beam member is made of commercial grade steel or aluminium, and the sheet material preferably has substantially uniform thickness. The precise embossment pattern created by the structural embossing can take a wide variety of forms. For example, the embossing could create an array of separate individual deformations on the sheet or alternatively a series of elongate continuous deformations or corrugations could be provided extending parallel to a deformation axis.

Preferably the array or said deformation axis is set at an angle to the longitudinal axis of the beam member. In particular, the deformation axis of the corrugations can be set parallel to the members longitudinal axis but alternatively it may be set transversely. The individual deformations of the array pattern can have a variety of shapes in plan view. Thus these deformations could be of rectangular, circular, square or oblong shape in plan with other shapes possible. Further, deformations of different planar shape could be present in a particular array.

Thus the structural embossment of the sheet material improves the structural strength property of-the metal sheet and hence of the complete beam member, enabling a thinner sheet to be used with a consequent saving in material and hence in cost, or alternatively, for a given wall thickness, increased structural strength is imparted to the beam member.

Embodiments of the present invention will now be described with reference to the accompanying drawings wherein: Figs. 1 and 4 show end views of building beam members made from sheet metal material and in accordance with the present invention.

Fig. 5 shows a perspective view of a building beam according to another embodiment with suitable structural embossing applied to the beam.

Fig. 6 shows one form of structural embossment suitable for use in the invention, while Fig. 7 shows a sectional side view of a deformation of Fig. 6 through section X-X in Fig. 6.

Fig. 8 shows another form of embossment pattern; and Fig. 9 shows a variation of the embossment pattern shown in Fig. 6.

Referring to Figs. 1-5 of the drawings, a building beam 1 constituting for example a roof purlin, roof beam or side rail, or eaves beam or valley beam is formed from sheet metal material and comprises a longitudinally extending main body part 2 and flange formations 3, 4 at respective edges 5, 6 of the part 2. The flange formations 3, 4 include horizontal surfaces 7, 8 to enable the beam 1 to be suitably mounted and also to facilitate load carrying by the beam. In Figs. 1 and 3-5 the flange formations 3, 4 are oppositely directed while in Fig. 2 these formations project towards the same side, and the flange formations 3, 4 preferably carry reinforcing ribs 9, 10. These beam members 1 usually perform the function of providing a structural connection between the roof sheeting and the wall sheets and the main structural frame of a building.

In each of the above embodiments, the sheet material of the beam member 1 comprises commercial or profiling quality steel or aluminium.

Commercial or profiling quality steel would be satisfied by designations M1 and E2 of British Standards 2989 (1982) i.e. defined as low grade commercial or profiling quality steel. The steel will be suitably coated and/or galvanised. The sheet material of the beam 1 is structurally embossed, and the embossing E has the function of strengthening the sheet material and also strain hardening the material. The embossing may be applied substantially over the full area of the beam, but it would be possible for the embossing to be applied at only selected areas. As a further alternative, different areas of the beam could have different embossment patterns.

The actual embossment pattern can be chosen from a wide variety of different forms, and Figs. 6, 8 and 9 merely show several examples. Thus in Fig. 6, the embossment applies an array of separate individual deformations 11, 12. As can be seen in Fig. 6 the deformations 11 are of oblong form in plan view while the deformations 12 are of a smaller circular shape, the pattern arrangement being defined by an orthogonal series of lines K-K, L-L with each circular deformation 12 surrounded by four oblong deformations 11. The spacing of lines K-K, L-L specify the pitch of the deformation array: a pitch of 5 rtrn may be used for example.The structural embossing is achieved by a cold deformation using for example a suitable embossment tool e.g. rollers, and it is a feature of the embossment that the orthogonal lines K-K, L-L are oblique to the rolling direction R.

Where the embossing of Fig. 6 is applied to the sheet material forming the beam, the longitudinal axis S-S (Fig. 5) of the beam will correspond with the rolling axis R so that the deformation array 11, 12 will be oblique to the longitudinal axis S-S of the beam i.e. the orthogonal lines K-K, L-L will be oblique to this axis. It is also arranged that the thickness t (Fig. 7) of the sheet material remains substantially uniform over the area of the material even after the embossing process.

It will be understood that deformations of other planar shape could be presented in the array of Fig. 6 for example deformations of rectangular or square form could be used. Further, different patterns are possible such as for example a uniform array of similar deformations, and an irregular (non-uniform) deformation array is also possible.

Fig. 8 shows embossing E of corrugated form with nodes 13, 14 and the ratio of pitch P to valley depth H can be suitably chosen. The embossment of Fig. 8 may be the preferred form in many instances and this embossment form is used in the beam of Fig. 5. The corrugations shown in Fig. 8 are of micro form. Where the beam member 1 is provided with the corrugated embossment of Fig. 8, the axis of deformation (i.e. out of the plane of the paper in Fig. 8) of the profile can be arranged appropriately relative to the longitudinal axis S-S of the beam. For example, the profile deformation axis may be arranged longitudinally to the longitudinal axis S-S.

Fig. 9 shows an embossment pattern E generally similar to that of Fig. 6 but with the distinguishing feature of two circular deformations 12 being surrounded by four oblong deformations 11. As will be readily appreciated, even further variations are possible. in all cases it is preferred that the embossment has the effect of increasing a structural strength property e.g. bending resistance of the sheet material by at least 5 per cent. Where a plastics coating is to be applied to the material the embossment may be carried out before or after the coating is applied.

The thickness of the sheet may be within the range 25 rtrn to 5 rrrn for example and the beam 1 will have a suitable length to meet the span required.

The application of the embossment to the sheet material of the beam in accordance with the present invention provides two distinct advantages concerning structural and aesthetic enhancement. Thus, the embossment increases the strength of the beam and this will enable thinner sheet material to be used thereby lightening the beam and consequently giving rise to a possible saving in cost since less metal is required. Also varying quality of metal mateial may be utilised as the stain hardening and cold deformation of the material due the embossment process mitigates against adverse effects created by the use of varying quality material.

Further, the embossing deformations will increase the corrosion resistance of the sheet material.

The deformations 11, 12 can be arranged to project so as to be visible externally and this improves the aesthetic qualities of the beam. In the case of the corrugated embossment of Fig. 6, at least one face of the profile, for example the surface with nodes 13, can be suitably coated with synthetic material. The stronger structurally embossed building beam members will enable the use of a lighter and cheaper structural steel work supporting frame for these components.

Claims

1. A support beam member for a building, formed from sheet metal material comprising a longitudinally extending main body part with a lateral flange at at least one edge of said main body part, said sheet material being structurally embossed so as to strengthen the material.

2. A support beam member as claimed in claim 1, wherein the structurally embossed sheet material has strength properties at least five per cent greater than a corresponding non-embossed plane sheet of a thickness equivalent to the material before it is structurally embossed.

3. A support beam member as claimed in claims 1 or 2, wherein the sheet material of the beam member is made of commercial grade steel or aluminium.

4. A support beam member as claimed in any one of the preceding claims, wherein the sheet material has substantially uniform thickness.

5. A support beam member as claimed in any one of the preceding claims, wherein the embossment provides an array of separate individual deformations on the sheet.

6. A support beam member as claimed in any one of claims 1 to 4, wherein the embossment comprises a series of elongate continuous deformations or corrugations.

7. A support beam member as claimed in claim 5 wherein the array of separate deformations is arranged as a pattern having orthogonal axes and one of said axes is set at an angle to the longitudinal axis of the beam member.

8. A support beam member as claimed in claim 6, wherein the continuous deformations or corrugations extend parallel to the longitudinal axis of the beam member.

9. A support beam member as claimed in claim 6, wherein the continuous deformations or corrugations extend at an angle to the longitudinal axis of the beam member.

10. A support beam member as claimed in claim 9, wherein the deformations or corrugations are set transversely to the longitudinal axis of the beam member.

11. A support beam member as claimed in claim 5, wherein the deformations are of rectangular, circular, square or oblong shape in plan view.

12. A support beam member as claimed in claims 5 or 11, wherein the array includes deformations of different planar shape.

13. A support beam member as claimed in claims 5, 11 or 12, wherein at least some of the deformations are flat topped.

14. A support beam member as claimed in claim 5 or any of the claims 11 to 13, wherein at least one deformation of one shape is surrounded by deformations of another shape.

15. A support beam member as claimed in any one of the preceding claims wherein the sheet metal has a thickness in the range 0.25 mm to 5 mm.

16. A support beam member as claimed in any one of the preceding claims, wherein a coating is applied to the metal sheet.

17. A support beam member substantially as hereinbefore described with reference to and as illustrated in any one of Figs 1 to 5 includiong the embossed pattern show in any one of Figs 6 to 9 of the accompanying drawings.