Method of forming metal

Abstract

 A method of forming metal to produce structural steel sections, the method involving the step of hot rolling an elongate section in a universal rolling mill stand having a first pair of rolls located at right angles to a second pair of rolls.
In order that the finished product can have oppositely disposed flanges (16,16) with side flanges (18,18) parallel to a web portion (14) of the section, the second pair of rolls (12,12) are located in such a position in relation to said first pair of rolls (10,10) that the side flanges (18,18) of the product are rolled between end portions of the first pair of rolls (10,10) and the respective flanks of the second pair of rolls (12,12).

Description

[0001] The invention relates to a method of forming metal, in particular for making structural steel sections.

[0002] The usual method of making structural steel sections is by hot rolling between a single pair of rolls, or through a succession of single pairs of rolls, or at least in so far as the finishing passes are concerned. Sections such as rolled steel joists, that is to say I-sections, and channel sections and angle sections are commonly produced in this way. If more complex sections are required these are usually produced by an extrusion process through special dies. For this reason, such complex sections are usually made of aluminium because, being a relatively soft and ductile metal, it is fairly easy to extrude. However, for this same reason it is not a good structural material and has only a fraction of the strength of steel.

[0003] The invention as claimed is intended to provide a remedy and seeks to solve the problem of how to produce structural steel in complex sections.

[0004] The advantages offered by the invention are mainly that by virtue of the fact that the sections are produced by rolling, relatively heavy and very strong sections can be produced. A further advantage offered by the invention is that the method of forming the sections produces shapes previously only obtainable by extrusion and shapes which are especially useful as structural steel sections.

[0005] One way of carrying out the invention is described in detail below with reference to the accompanying drawings, of-which:-

Figure 1 is a diagrammatic illustration of a rolling operation embodying the inventive method, and

Figure 2 is a diagrammatic illustration of a possible further step in the method,

Figure 3 is a view similar to Figure 1 and illustrating the rolling of a further form of section,

Figures 4 and 5 are views similar to Figure 2 and which illustrate alternative ways of performing a possible further step in the inventive method on the semi-finished section of Figure 3,

Figure 6 is a view similar to Figure 1 and illustrating the rolling of a still further form of section,

Figures 7 and 8 are views similar to Figure 2 and which illustrate alternative ways of performing a possible further step in the inventive method on the semi-finished section of Figure 6.

Figures 9 and 10 are still further views similar to Figure 1 and illustrating the rolling of further forms of sections,

Figure 11 is a partly cut-away view showing how structural steel sections produced by the inventive method might be connected together, and

Figure 12 is a sectional view on the line 12-12 in Figure 11, and

Figures 13 to 16 are further views which will be referred to when describing further possible modifications.

[0006] Referring now to Figure 1 of the drawings, the rolling operation there illustrated is shown being carried out on a so-called universal rolling mill stand in which two pairs of rolls, 10,10 and 12,12 are located, the pairs of rolls 10,10 being rotatable about horizontal axes and the pair of rolls 12,12 being rotatable about vertical axes. As shown, the rolls 10,10 are profiled to produce a web 14 at the neutral axis of the finished section and the rolls 12,12 are of such a width and are located at such a position in relation to the rolls 10,10 that the oppositely disposed flanges 16,16 of the section are provided with pairs of side flanges 18,18 equally spaced about the neutral axis of the section. The side flanges 18,18 are shown being rolled between the end portions of the rolls 10,10 and the flanks of the respective rolls 12,12.

[0007] It will be seen that the finished section is a relatively complex section of the sort which might normally be made of aluminium by an extrusion process. However, it will be understood that when produced by the rolling operation described the section can be made of ferrous metals, and even of stainless steel. When used as structural steelwork, the section will be particularly useful by virtue of the fact that the grooves 20 between the spaced pairs of side flanges 18,18 can be used for the reception of the side edges of glazing or wall panels.

[0008] In Figure 2 there is illustrated a possible further step in the method, this being the bending of the rolled section to the configuration shown in full lines. If the web of the section is relatively thick, this further step will of course be performed whilst the rolled section is still hot. However, if the web is relatively thin it may well be performed cold and perhaps on site where the section is being used. There is thus produced a structural steel section forming a corner member, and glazing or wall panels can, in the illustrated example, extend at right angles to each other. It will also be seen that in the illustrated example the bending of the rolled section through a right angle has produced an almost completely closed cavity 22 within the section (which could in fact easily be completely closed, if preferred, instead of having the narrow gap as shown. it could be closed by bending the rolled section rather more or could be closed by the addition of a metal or plastics closure strip or of course it could be closed by welding). In use, the cavity 22 within the section may be used, for example, for the reception of electrical wiring. The seam could of course be welded either by means of a continuous weld or by spaced apart tack welds.

[0009] Referring now to Figure 3, it will be seen that the rolled section need not necessarily be symetrical about the neutral axis; in this illustrated example the rolls 10,10 have been modified so that, in the section produced, the web 14 is in line with the side flanges 18 at one side of the section. However, as in the first example, it will be seen that the side flanges 18,18 are again being rolled between the end portions of the rolls 10,10 and the flanks of the respective rolls 12,12. A possible further step in the forming of the section is illustrated in Figure 4, this again being the bending of the rolled section to the configuration shown in full lines to produce a structural steel section for forming a corner member. This further step has again produced a cavity 22 within the section in which electrical wiring can be received when the section is in use. An alternative possible further step in the forming of the rolled section of Figure 3 is illustrated in Figure 5, this being the bending of the rolled section in the opposite sense to the configuration shown in full lines, but of course in this case the finished section does not have a central cavity within it.

[0010] In Figure 6 there is illustrated a rolling operation being carried out to produce a slightly more complex shape of section than hitherto although being carried out in basically the same way as the rolling operations previously referred to, that is to say with two pairs of rolls 10,10 and 12,12. However, the main variation in this case is the profiling of the rolls 12,12 as shown so that the flanges of the finished product are of varying thickness. As shown in Figures 7 and 8, the rolled product can subsequently be deformed to form finished . product similar to the sections illustrated in Figures 4 and 5 but it will be seen that the varying thicknesses of the flange parts lend themselves ideally to drilling and tapping for the reception of bolts, screws or rods.

[0011] it will be understood that numerous other variations may be made on the basic structural steel section which can be produced by the inventive rolling operation. For example, in Figure 9 there is illustrated a rolled section in which the web 14 is offset from the side flanges 18. In Figure 10 there is illustrated a further variation in which the depth of section is greatly increased and the rolled section has three pairs of oppositely disposed side or auxiliary flanges 18,18. It will be understood that in these cases also the pairs of side flanges will be rolled between the end portions of the first pair of rolls and the respective flanks of the second pair (or pairs) of rolls. Although not illustrated it will be understood that any of these variations of rolled section may be further worked on whilst still hot to bend the web 14 through a right angle, or through some other required angle (and indeed may be similarly worked when cold if the web of the section is relatively thin).

[0012] In Figures 11 to 14 there are illustrated ways in which the sections depicted in Figures 6, 7 and 8 might be used for building a greenhouse or conservatory (although of course simple low cost housing units could be built in just the same way). Figure 11 is a vertical section through a length of product similar to that of Figure 8 (except that the web has not been deformed through as great an angle) the length of product forming a transition between a side wall and sloping roof of the structure. Spaced roof spars 24 are formed by similar sections of product the mating ends of which have been formed by shearing and jig milling. It will be seen that the length of product referred to is used in combination with another section 26, small blocks 28 being fitted between the two, as shown, so that the widest flange is on the outside. A length of light metal or plastics plate 30 which is bolted at intervals to the length of rolled and formed product constitutes a length of rainwater guttering.

[0013] Figure 12 is a view very similar to Figure 11 except that in this case the length of product forming a transition between a side wall and sloping roof of the structure is a product similar to Figure 7 (but the web of the rolled section has not been deformed through as great an angle as that of Figure 7). Spaced roof spars 24 are again formed by similar sections the mating ends of which have been formed by shearing and jig milling. The section 26 is here shown to constitute a base section laid on a concrete base 100 and spaced side wall support posts 25 have been appropriately formed at their upper and lower ends by shearing and jig milling.

[0014] In Figure 13 there is illustrated in horizontal section the use of a length of product similar to that of Figure 7 for forming a corner of the structure (except that in this case the operation of deforming the web of the section has not produced a closed cavity within the length of product). As shown, a double glazed unit 32 has been fitted on one side of the corner section and a single glazed unit 34 has been fitted on the other side of the section. In each case, the glazing unit has been fitted in a rubber or soft plastics lining material 34 and has been secured by clamping strips 36 bolted in position by bolts 38. The aperture opening into the cavity 22 is shown to have been closed by a plastics strip 40 snap fitted in position. (Although the units 32 and 34 have been referred to as glazing units, some of the units could be simple panel units. If the structure is a low cost housing unit, some at least of the items 32 and 34 could be thermally insulated panels).

[0015] It will be understood that if the structure built up as illustrated in Figures 11 to 13 is a greenhouse or conservatory, the glazing units 32 and 34 may extend the full height of the side wall of which they form a part. However, the glazing panels may be somewhat smaller panels located in vertically arranged groups between the pairs of support posts. In this case, as illustrated in Figure 14, the support posts will be drilled at intervals for the fitment of bolts 40 extending into drilled and tapped holes in the ends of cross members 42 made of similar section product the ends of which have been prepared by shearing and jig milling.

[0016] The sections which can be produced by the inventive method of rolling are of course capable of being assembled to form the skeletal structure of a building much larger than a greenhouse or conservatory, for example a multi-level structure providing low cost housing units. Such a skeletal structure may be built up with connections similar to those illustrated in Figures 11 to 14. The webs of the uprights can be drilled at appropriate heights for the bolting of floor supporting cross members thereto.

[0017] It will of course be understood that various other sections may be produced using the inventive method to add the at least one further dimension to the sections customarily produced by hot rolling. For example, in Figure 15 there is illustrated a further possible section similar to that shown in Figure 3 but having a further pair of main flange portions which, as the section is viewed in Figure 15, have been formed by the profiling of the top roll. In Figure 16 there is illustrated one example of how such more complex sections might be used for building a structure.

[0018] In Figures 17 and 18 there are illustrated further sections which could be produced by the inventive method, that of Figure 17 being shown to have a wavy formation on the outer surface of the section (which can be considered to.be formed by pairs of side flanges on the main flange portions 16,16) and that of Figure 18 being shown to have elongate grooves forming side flanges along the edges of the main flange portions 16,16. However, it will be understood that the outer surfaces of the main portions need not necessarily be provided with elongate grooves or flanges. The rolls which act on the outer surfaces _'of the main flange portions may be such as to apply, for example, a pattern effect on those surfaces; for example a knurled effect could be produced. These are effects which cannot possibly be obtained by conventional rolling.

[0019] Various other modifications may be made and it will of course be understood that the hot rolled steel sections produced by the inventive method may have numerous other uses. The possible further step in the method, that is to say the bending of the rolled section to produce a section forming a corner member, may be carried out in various ways on any of the rolled sections referred to and will present no problem to those skilled in the art. For example, whilst still hot it may be carried out in further roll passes or by the rolled product being passed through dies similar to extrusion dies but acting merely to bend the web of the section rather than to extrude it.

Claims

1. A method of forming metal, the method including the step of hot rolling an elongate section in a universal rolling mill stand having two pairs of rolls, that is to say a first pair of rolls (10,10) mounted for rotation about parallel axes and a second pair of rolls (12,12) each mounted for rotation about an axis in the same vertical plane as said first pair of rolls but at a considerable angle thereto, characterised in that said second pair of rolls (12,12) are of such a width and are located at such a position in relation to said first pair of rolls (10,10) that oppositely disposed flanges (16,16) of the finished section are provided with pairs of side flanges (18, 18) located in planes parallel or substantially parallel to the web (14), said pairs of side flanges being rolled between end portions of.the first pair of rolls (10,10) and the flanks of the respective rolls (12,12), or are provided with surface finishes not capable of being applied when using only a single pair of rolls.

2. A method according to claim 1, further characterised in that it includes the further step of bending the web (14) of the rolled section, thus producing a section forming a corner member in which one pair of side flanges (18,18) are disposed at an angle relative to the other pair.

3. A method according to claim 2, further characterised in that the further step referred to has formed a closed or nearly closed cavity (22) within the section, the method including the still further step of welding the seam either by a continuous weld or by spaced apart tack welds.

4. A universal rolling mill stand having two pairs of rolls, that is to say a first pair of rolls (10,10) mounted for rotation about parallel axes and a second pair of rolls (12,12) each mounted for rotation about an axis in the same vertical plane as said first pair of rolls (10,10) but at a considerable angle thereto, characterised in that the first pair of rolls (10,10) are profiled to produce a web portion (14) of a hot rolled steel section product and to define the overall width of main flange portions . (16,16) of the product and said second pair of rolls (12,12) are of such a width and are capable of location at such a position in relation to said first pair of rolls (10,10) that the oppositely disposed main flange portions (16,16) of the finished section are provided with pairs of side flanges (18,18) located in planes parallel or substantially parallel to the web (14) of the section or provided with surface finishes not capable of being produced when using only a single pair of rolls.

5. A universal rolling mill stand according to claim 4, further characterised in that the second pair of rolls (12,12)are shaped so that they produce more than two pairs of side or auxiliary flanges (18,18) on the main flange portions (16,16) of the product.

6. A universal rolling mill stand according to either one of claims 4 and 5 further characterised in that it is associated with further means whereby the web (14) of the rolled product can be bent whilst still hot, thus producing a finished product forming a corner member having at least two pairs of side or auxiliary flanges (18,18)projecting in different directions.

Drawing