US2376574A - Method of producing structural members - Google Patents

Description

T. COLLINS May 22, 1945.

METHOD OF PRODUGING STRUCTURAL MEMBERS FiledlApril 7, 1942 Tk PPH/V C GA A INS ATTORNET Patented May 22, 1945 METHOD OF PRODUCING STRUCTURAL MEMBERS Tappan Collins, Dormont, Pa., assignor to Carnegie-Illinois Steel Corporation. a corporation of New Jersey Application April 7, 1942, Serial No. 438,043

3 Claims.

The present invention relates to specific features of improvement in the method of producing structural members rapidly and economically.

Various objects and advantages resulting from the adoption and use of the invention will be apparent from the following detailed description,

when read in connection with the accompanying drawing and the features of novelty will be defined in the appended claims.

In the drawing:

Figure 1 illustrates a step in the method;

Figure 2 illustrates a further step in the method;

Figure 3 illustrates a step following that illustrated in Figure 2 wherein a separately formed weiadmember is united to a flange element by fillet we s;

Figure 4 is a cross section of a completed structural member made in accordance with the invention;

Figure 5 is a view similar to Figure 3 illustrating an alternative method wherein the preliminary joining of the web member to the flange member is accomplished by fusing the parent metal of the flange member; and

Figure 6 is a cross sectional view of a structural element produced by following the method illustrated in Figure 5.

Referring in detail to the drawing, in practicing the method of the present invention I provide a flanged member substantially or approximately of the cross sectional shape shown in Figure 1 which includes side flanges ID and I2 which are obliquely inclined with respect to one another, the angle of inclination being symmetrical about the vertical axis a:--:c. The flanged element is provided with a V-shaped notch l4 which is flanked by thickened bodies of fillet metal I6 and I8.

The flanged element such as shown in Figure 1 can be readily produced from blooms or billets similar to those from which standard structural I-beams, channels, rails and the like are usually formed by conventional forms of rolling mill equipment.

The flange element of Figure 1 is next bent to the condition illustrated in Figure 2 by forcing a blade 20 toward the v-shaped notch l4 and into contact with the curvilinear base 22 thereof. Continued downward movement of the blade 20 will cause flexure of the metal in the region of the axis :c-a: so as to thus flatten the flange member to the condition shown in Figure 2 wherein the flanges occupy approximately a common horizontal plane as shown. Thus there is produced the intermediate flanged element with a narrow central slot extending longitudinally thereof, the width of which is determined by the thickness of the blade 20. The blade is then withdrawn and a web plate 24 is inserted in the slot flanked by the fillet bodies l6 and I8. Then a plurality of preliminary tack welds 26 are made at a plurality of longitudinally spaced points. These spaced tack welds serve to temporarily unite the web plate 24 to the flanged member. Thereafter permanent fillet welds are made so as to homogeneously unite the flange metal to the web metal in the region of the fillet bodies l6 and i8. Otherwise expressed, a homogeneous union of the two metals is made by establishing a zone of fusion in the region such as indicated at 28 in Figure 4.

The described tack welds and fillet welds are made by depositing extraneous metal from a welding rod or the like. However, the method is not confined to such use of extraneous metal. As illustrated in Figures 5 and 6, I may fuse a portion of the parent metal, for example that indicated in the region of the zone 30 in Figure 5, in order to make the temporary connection between the web plate 24 and the flanged member. Thereafter a continued welding operation will be carried on so as to homogeneously unite the web plate with the flange member by a zone of fusion such as indicated at 28 in Figure6. Thus an autogenous welded union between the flange element and the web plate is efiected.

' By the practice of the invention the flange element as above indicated can be produced as an integral metal piece by rolling on a standard structural mill and the notch II can thus be precisely formed economically by eliminating conventional make-ready requirements such as the elimination of precise sizing and special edge conditioning of the web plate element and block ing, clamping or jigging separately pieces in position for welding. The substantially V-shaped central notch can be rolled to a predetermined size and shape to receive a web plate 24 of any desired thickness or gauge and the web plate utilized can be of stock flat rolled material pro ducible on a quantity basis by conventional rolling mill methods.

The flared-shaped notch 14 illustrated has an arcuate apex portion 22 and is of a contour devoid of reentrance angles and is also devoid of parallel faces. Thus the notch can be readily formed by a rolling operation in a mill. Likewise the outer arcuate fillet faces 32 and 34 can similarly be produced by a rolling operation. It is noted that the converging side faces 38 and II of the notch l4 are disposed approximately at right angles to the planes of the underfaces 40 and 42 of the flange portions l and I2. The upper edge faces 44 and 46 of the fillet bodies It and it are approximately parallel to the planes 40 and 42 and are, therefore, perpendicular to the notch faces 36 and 38.

With the blank of the configuration shown in Figure 1 it will be apparent that upon bending the same to the condition of Figure 2, the same will be flattened. In this operation a lower die, not shown, will be employed and the metal will be worked in the region of the line a:.'c of Figure l; by reason of the downward bending force exerted by the blade 20. As the blade descends the bottom faces 40 and 42 of the flanges i0 and I2 will be flattened against the bottom die and at some stage of this operation the notched faces 38 and 38 will come into contact with the opposite side faces of the descending blade 20. From that stage on, to the completion of the flattening operation, two edges of the rolled section will be maintained in spaced relation by the blade 20 so that the final width of the slot betweenthe plane faces 36 and 38 will have been determined by the thickness or gauge of the blade 20. It is therefore apparent that by selecting a blade of predetermined thickness a slot of any desired width can be readily produced.

In the bending operation it will be observed that in the initial stages only the central portion of the rolled blank of Figure 2 is subjected to working. Thereafter there is added a component of elongation which continues throughout the latter phases of the flattening operation as the blade continues to descend from the position intermediate that shown in Figure l to the position of Figure 2. Close analysis of the exact nature of this deformation will confirm that what at first glance appears to be a pivoting about the edges 36 and 38, with consequent unrelieved elongation during the latter phase of the flattening operation, does actually involve sliding the edges Elli and 38 vertically downward along the side faces of the blade 20 and that the flattening operation is in reality a bending operation from start to finish about a centroid that is progressively displaced upward. There may, and with blades of preferred thickness there will, continue to be compression of the metal at the arcuate bottom or base of the groove I4 throughout the whole cycle of the flattening operation.

In some cases I contemplate a slight overflattening operation, by which I mean the blade 20 may be caused to move down to such an extent that it will depress the central portion of the flanged element to a plane below the true horizontal to thus dispose the outer flange portions to the positions indicated at dotted lines in Figure 2. This overfiattening will compensate for the tendency of the parts to spring back after the flattening operation and will generally be required only in the case of very heavy sections or when using a blade of maximum allowable thickness. It may also be desirable to apply heat to the central median region of the section corresponding to its zone of deformation.

After the rolled steel flange member has been conditioned as shown in Figure 2, the flat rolled steel web plate 24 will be inserted in the central notch to a sufficient depth and the parts may be maintained in assembled relation such as shown in Figure 3 solely by friction due to their mutual interengagement. However, in some cases I contemplate making temporary tack welds at spaced points prior to the final welding to the condition shown in Figure 4. The depth of slot between the faces 28 and 38 will usually be greater than will be actually required in order to secure the minimum required engagement and therefore the depth (not thickness) dimension of the web plate element may vary within the limits and still permit the overall dimension of the assembled section to be that desired. Moreover, since the concealed edge of the web plate element need not necessarily be seated against the bottom of the notch i4, the condition of the extreme inner edge of the web plate 24 is of no significance to the construction, hence no special finishing of this edge is required.

In Figure 3 there is shown a clearance between the lower edge of the web plate 24 and the notch in which it is seated so as to pictorially represent this point. This is a feature of practical importance in the interest of economy since certain irregularities and working tolerances can thus be allowed for. The utilization of temporary tack welds described secures the parts in position for final welding without the use of relatively expensive blocking, clamping or jigging devices. The final homogeneous union of the web plate to the flanged element may be accomplished either by fillet welding, as illustrated in Figures 3 and 4, or by use of a carbon arc, an autogenous weld may be secured by fusing the parent metal, as illustrated in Figures 5 and 6.

From the foregoing it is apparent by the practice of the improved method set forth, I make available accurately dimensioned flanged striictural members which are fabricated from rolled web and flange elements whose dimensions need not be precise either as to width dimension or as to edge conditioning. Thus rough rolling tolerances can be allowed. The welded joints are of such nature that the sections So fabricated will be precisely and generously fllleted without resort to elaborate or extravagant weld metal deposition or finish grinding.

By reserving one determinant manipulation of the rolled shape, -viz., its flattening with coincident slot forming, it is possible to employ a desired single size and weight of flange element for application to web plate elements of a variety of thicknesses.

By engaging the web plate in a squared and fitted slot in the flange element, any waviness of the edge of the web plate or any tendency for it to become wavy during welding is rendered inconsequential by positioning the edge of the web plate element in spaced relation to the flange element throughout the length of the section.

By employing a flange element which can, by tack welding alone, be fixed in proper relative position with the web plate, with which it is to be united by fusion welding, my invention dispenses with any necessity for blocking, clamping or jigging the separate elements preparatory to welding.

An important advantage to be secured by the adoption and use of this invention arises from a particular. construction of the component parts that are homogeneously united by bodies of fused metal or spliced together by welding after their separate fabrication. By extending the web plate beyond the ends of the flange elements for one of two abutting weldment ends and extending the flange elements a corresponding distance beyond the end of the web plate element for the other,

butt welding of web plate elements and flange elements and full fillet welding of the lapped elements without resort to the use of splice plates, temporary bolts, clamps or other auxiliaries and without effecting a break in any of the lines of construction.

While I have described a preferred method and procedure, it is to be understood that the specification and drawing are to be interpreted in an illustrative rather than a limiting sense, since various modifications may be made by those skilled in the art without departure from the invention as defined in the appended claims.

,I claim:

1. In the manufacture of structural members, the method which comprises providing a rolled element with side flanges obliquely inclined and with a flared notch between them, forcing a blade of predetermined thickness against the base of the notch so as to flatten said element and bring the side walls of the notch into approximately parallel relation, withdrawing the blade and inserting a rolled metal plate in said notch and welding the plate to said element.

2. In the manufacture of structural members,

the method which comprises subjecting'a blank 30 to a rolling operation so as to provide a flange element having obliquely disposed flanges with thickened inner flllet portions flanking an outwardly flaring notch, forcing a blade'of predetermined thickness against the base of .said notch So as to bring the outer faces of the flanges into approximately a common plane and at the same time to bring the inner faces of the flared notch approximately into parallelism, Withdrawing the blade and inserting a flat rolled metal web plate of approximately the same thickness as the blade into the notch, and welding it to said fillet portions.

3. In the manufacture of structural members, the method which comprises subjecting a blank to a rolling operation so as to provide a flange element having obliquely disposed flanges with thickened inner fillet portions flanking a centrally disposed outwardly flaring notch formed with a curvilinear median fillet, forcing a blade of predetermined thickness against said fillet so as to bring the outer faces of the flanges approximately into a common plane and at the same time to bring the inner faces of the flared notch approximately into parallelism, withdrawing the blade, inserting a rolled metal web plate of substantially the same thickness as the blade into the notch, the extent of the inserting movement of the plate being such that it clears said fillet, tack welding the web plate to said element at a plurality of longitudinally spaced points to temporarily hold the parts, and thereafter permanently welding the web plate to the thickened portions of fillet metal.

TAPPAN COLLINS.

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