GB2102465A

GB2102465A - Rolled metal beam

Info

Publication number: GB2102465A
Application number: GB08122986A
Authority: GB
Inventors: Andrew Peter Jerrard-Dunne
Original assignee: JERRARD DUNNE ANDREW PETER
Current assignee: JERRARD DUNNE ANDREW PETER
Priority date: 1981-07-24
Filing date: 1981-07-24
Publication date: 1983-02-02

Abstract

An I- or H-section beam rolled from a strip of metal, e.g. steel, has a central web (36) of a single thickness of the strip and two flanges (32 and 34) each formed by folding the strip away from the central web 36 and folding the strip again through 180 DEG to form one edge (40, 42) of the flange, the strip then extending continuously to the opposite edge (38, 44). The strip may be folded over for a short distance at the lower edge to strengthen the edge and make it smooth. <IMAGE>

Description

SPECIFICATION Beam This invention relates to beams.

More particularly the invention relates to beams of I-section or H-section. Such beams are used extensively in building.

It is known to manufacture such beams by rolling a strip of steel or other suitable metal so that the strip is folded as shown in cross-section in Figure 1 of the accompanying drawings. In this known beam, having two flanges 10 and 12 joined by a central web 14, the beam is symmetrical about the central web, the strip being folded over itself at two opposite edges 1 6 of the flange 10 and then extending in double thickness along the central web 14 and dividing to extend in single thicknesses to the opposite edges 18 of the other flange 12.

This invention consists in a beam rolled from a strip of steel or other suitable metal to form an Isection or H-section having two flanges connected by a central web, in which the central web is of a single thickness and each flange is formed by folding the strip away from the central web and folding the strip through 1 800 to form one edge of the flange, the strip then extending continuously to the opposite edge of the flange.

One embodiment of the invention is illustrated in Figure 2 of the accompanying drawings.

As shown in Figure 2, the beam 22, which is rolled from steel strip, has parallel upper and lower flanges 32 and 34 joined by a web 36 perpendicular to the flanges. The strip extends in a single thickness from one edge 38 of the upper flange 32 and is folded over at the opposite edge 40 of the flange, so that the part of the flange 40 on that side of the web 22 is of double thickness.

The strip then continues through 900 to form the central web 22, which is of single thickness. The lower flange 34 is similar to the upper flange 32, the strip being folded over at one edge 42 and extending to the opposite edge 44. The strip is also folded over a short distance at each of the extreme edges 38 and 44 to form welts which strengthen the beam at those edges and also provide smooth edges.

As compared with the conventional construction of such a beam, the beam of the invention uses less material and so is of less weight for a given size, and is less expensive. The strength of the described beam also enables steel of less thickness to be used, reducing the weight still further. For example, a beam of conventional construction having a web of 30 mm width would typically use steel of at least 0.8 mm nominal thickness, whereas the described beam can be made from steel of 0.55 mm nominal thickness.

The beam also has the advantage that the outer face of the lower flange 34, as well as that of the upper flange 32, has a smooth finish with no central crease due to folding of the strip.

Claims (Filed on 23 July 1982) 1. A beam rolled from a strip of metal to form a section having two flanges connected by a central web, in which the central web is of a single thickness and each flange is formed by folding the strip away from the central web and folding the strip again through 1800 to form one edge of the flange, the strip then extending continuously to the opposite edge of the flange.

2. A beam as claimed in claim 1, in which the strip is folded over for a short distance at the said opposite edge of each flange to form a welt.

3. A beam as claimed in claim 1 or claim 2, in which the flanges are parallel to one another.

4. A beam as claimed in claim 3, in which each flange extends at 900 to the central web.

5. A beam as claimed in any preceding claim, in which the metal is steel.

6. A beam substantially as described with reference to, and as shown in, Figure 2 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Beam This invention relates to beams. More particularly the invention relates to beams of I-section or H-section. Such beams are used extensively in building. It is known to manufacture such beams by rolling a strip of steel or other suitable metal so that the strip is folded as shown in cross-section in Figure 1 of the accompanying drawings. In this known beam, having two flanges 10 and 12 joined by a central web 14, the beam is symmetrical about the central web, the strip being folded over itself at two opposite edges 1 6 of the flange 10 and then extending in double thickness along the central web 14 and dividing to extend in single thicknesses to the opposite edges 18 of the other flange 12. This invention consists in a beam rolled from a strip of steel or other suitable metal to form an Isection or H-section having two flanges connected by a central web, in which the central web is of a single thickness and each flange is formed by folding the strip away from the central web and folding the strip through 1 800 to form one edge of the flange, the strip then extending continuously to the opposite edge of the flange. One embodiment of the invention is illustrated in Figure 2 of the accompanying drawings. As shown in Figure 2, the beam 22, which is rolled from steel strip, has parallel upper and lower flanges 32 and 34 joined by a web 36 perpendicular to the flanges. The strip extends in a single thickness from one edge 38 of the upper flange 32 and is folded over at the opposite edge 40 of the flange, so that the part of the flange 40 on that side of the web 22 is of double thickness. The strip then continues through 900 to form the central web 22, which is of single thickness. The lower flange 34 is similar to the upper flange 32, the strip being folded over at one edge 42 and extending to the opposite edge 44. The strip is also folded over a short distance at each of the extreme edges 38 and 44 to form welts which strengthen the beam at those edges and also provide smooth edges. As compared with the conventional construction of such a beam, the beam of the invention uses less material and so is of less weight for a given size, and is less expensive. The strength of the described beam also enables steel of less thickness to be used, reducing the weight still further. For example, a beam of conventional construction having a web of 30 mm width would typically use steel of at least 0.8 mm nominal thickness, whereas the described beam can be made from steel of 0.55 mm nominal thickness. The beam also has the advantage that the outer face of the lower flange 34, as well as that of the upper flange 32, has a smooth finish with no central crease due to folding of the strip. Claims (Filed on 23 July 1982)

1. A beam rolled from a strip of metal to form a section having two flanges connected by a central web, in which the central web is of a single thickness and each flange is formed by folding the strip away from the central web and folding the strip again through 1800 to form one edge of the flange, the strip then extending continuously to the opposite edge of the flange.

5. A beam as claimed in any preceding claim, in which the metal is steel.