US1760956A - Metallic structure and method of making same - Google Patents

Description

June 3, 1930. H. H. MOSS 1,760,956

METALLIC STRUCTURE AND METHOD OF MAKING SAME Filed Dec. 24, 1925 3 Sheets-Sheet 1 INVENTOR:

BY ,@wm

A TTORNEYS.

June 3, 1930. H. H. MOSS METALLIC STRUCTURE AND METHOD OF MAKING SAME Filed Dec. 24, 1925 5 Sheets-Sheet 2 INVENTOR:

/ ATTORNEYS June 3, 19300 H. H. MOSS METALLIC STRUCTURE AND METHOD OF MAKING SAME Filed Dec. 24, 1925 3 Sheets-Sheet 3 I VENTOR: M 9 4 BYI 2 g TORNEYS.

Patented June 3, 1930 UNITED STATES PATENT OFFICE HERBERT H. MOSS, OF IBELLEVILLE, NEW JERSEY, ASSIGNOR TO THE LINDE AIR PRODUCTS COMPANY, A CORPORATION OF OHIO METALLIC STRUCTURE AND METHOD OI MAKING SAME Application filed December 24, 1925. Serial No. 77,612.

This invention relates to metallic structures, and more articularly to improved means for and met ods of joining structural members.

Heretofore, the sub-members of a built-up structure, such as a bridge or roof truss, have been united by gusset plates overlapping and riveted or otherwise secured to the adjoining portions of such members. Such gusset plates produce an unsymmetrical section at the joints and the overlapping portions increase the weight of material in the structure without adding to its strength.

The primary objects of this invention are to produce a built-up structure in which the gusset plates comprising the joints between the component members throughout the structure shall lie in planes coincldent with the portions joined thereby, so that a plane of substantially homogeneous metal shall extend through the 'ointed structure; whereby the joints will e symmetrically stressed both in tension and shear or com ression and shear, to develop a high joint e ciency with less material.

Generally speaking, these and other obj ects are attained by inserting suitable gusset plates between the structural sub-members, such as angles, Ts, Z-bars, channels, I-beams, etc. and butt welding the meeting edges of such sub-members and inserted gusset plates. For this purpose, the improved gusset plates are desirably formed with one or more legs or extensions to fit the members terminating at a joint; the webs, legs or flanges of such members having been previously so formed or cut away, at the. portions thereof adjacent the joint, that they will interfit with the legs and other opposed portions of the inserted gusset plates.

The above and other objects and the novel features of this invention willbe apparent from the following description, taken with the accompanying drawings, in which Fig. 1 is a side view of a portion of a typical steel roof truss embodying this invention;

Fig. 2 is a perspective view of a joint embodying this invention;

Figs. 3 t0 6 inclusive are detail views of different types of joints em ciples of this invention; an

Figs. 7 to 10 illustrate various types of gusset joints.

Referring to Fig. 1, this invention is shown as applied in the erection of a common type of steel roof truss, but it will be understood that this showing is merely illustrative, since the invention is of more general application; as for example, in bridge trusses and other framework and in j o'ining non-ferrous as well as ferrous members. As shown, the truss section comprises a main rafter R which may consist of one or more angles or Ts; a bottom chord S in the form of one or more angles, Ts or other suitable shapes; a hanger H consisting of a T or other suitable shape; a number of diagonal members or struts A, B, C, D, E and F, either angles or Ts and the required number and types of gusset plates 15, 1e, 17, 1s, 19, 20, 21, 22 and 23 joining the aforesaid members together in proper relation to form the truss.

In general, the particular shapes and crosssectional areas as well as the positions of the various members and struts are selected or determined by calculations, as heretofore. The cross-sectional areas of the various gusset plates are likewise calculated by wellknown methods, to provide the required strength to take the loads which the framework is designed to carry. According to this invention, adjoining or contiguous portions of the sub-members or shapes to be connected by a gusset plate are partially removed or cut away to a predetermined extent to receive a similar portion of the gusset plate that is inserted in place of such removed portions; the alined members .and gusset plate being then welded or brazed together along their opposed or meeting ed es. The gusset plate is thus substantially ush with the parts adjoining the cut out portions, so that a plane of substantially homogeneous metal extends through the joint and the latter is symmetrical with the ad'oining members. The gusset plate and weids are so located that the joint is properly stressed in tension or compression as well as shear to loying the prinplates which may be employed in such transfer stresses uniformly through all parts of the adjoining shapes and thereby develop the highest joint efficiency and the full strengths of such members.

The principles of this lnventlon may be best presented by describing the procedure followed in joining two simple structural shapes or members, such as the similar angle irons K and L shown in Fig. 2. An lntermediate portion of one leg 25 of the angle iron K is removed in any convenient manner, as by cutting it out by means of a hack saw, an oxy-acetylene cutting torch, or otherwise. Similarly, a portion at the end of the coplaner leg 26 of the angle iron L is removed, the length of the removed portions desirabl being substantially greater than the widt of the leg. In this example, the angle K may correspond to the principal member of a framework and the angle L may correspond to a strut or other sub-member, the two angles being rolled shapes and located relatively to one another in the same position they. would occupy in a completed structure.

A gusset plate G is then inserted into the recesses left by the removed portions and welded in place of theremoved portions to integrally unite the angles. The gusset plate desirably consists of sheet steel or metal having substantially the properties of the legs of members K and L, and the plate preferably is of the same thickness as the cut out sections of the legs, and hasstraight or otherwise shaped edges to match those of the recesses produced by the cut out sections. Since the angle L is joined perpendicularly to the angle K, the gusset plate is desirably substantially triangular in plan, and its hypotenuse edge 27 extends between the inner edges 25, 26' of the legs 25 and 26. In the finished joint the gusset plate is disposed in the same plane with the legs 25 and 26, and is welded or brazed to the legs of the angle L along the shaded weld areas 28, 29 and to the legs of the angle K along the shaded weld areas 30, 3'1, 32. The leg 33 may but need not extend under or abut against the leg 25. The welding or brazing metal may be fused along the inside as well as along the outside of the several meeting edges. The members may be conveniently prepared and the gusset plates welded to one of them, preferably to the principal members, in the shop; so that little cutting and a smaller amount of welding will be necessary to complete the structure in the field.

The joints indicated as formed by the gusset plates 16 and 20 in Fig. 1, correspond in all essentials to the joint illustrated in Fig. 2. lVhere two independent angles or other shapes are to be joined to a principal member, gusset plates having two legs are employed, as indicated at 17 and 21 in Fig. 1; and the sub-membeis and main member are united thereto {in accordance with the above described welding procedure.

The connection formed by the gusset plate 18 is shown on a larger scale in Figs. 3 and 4. The base 181 of the gusset plate is brazed or welded into a cut out portion -of a leg of the angle or other shape that constitutes the bottom cord S, in the manner already disclosed. Similarly, the leg 182 of the gusset plate is welded into the cut away portion at the end of the angle forming the strut F. The strut C, as shown, may consist of a rolled T, the flanges 35 and 36 of which are cut off or otherwise removed for a substantial distance back from the end of the T, leaving the leg or web 37 in its original position. The leg 183 of the gusset plate may be cut out longitudinally to provide an elongated recess of appropriate size to receive the projecting end of the web 37, so that the ends of the flanges 35, 36 may be positioned adjacent the end of the gusset leg 183. Welding or brazing metal is then fusion deposited along the adjoining edges of the T and the leg 183 to produce the welds indicated by the shaded areas 38, 39, 40 and 184, thereby uniting these parts and providing a braced joint along the leg 183.

Gusset plates 19, 22 and 23 differ somewhat in shape from those already described, but they are similarly provided with integral legs and are inserted and welded in position in accordance with the procedure already described.

The gusset plate 15 is similarly fitted into recesses formed by removed portions at the adjacent ends of the rafter R and chord S, and is welded to the latter along the edges of such recesses.

TVhere it is desirable to use two shapes to form a single structural member, and then connect the latter to another structural memher, the procedure illustrated in Figs. 5 and 6 may be followed. Here, two rolled angles M, N placed back to back have their parallel legs 41, 42 removed or cut away to leave a recess to receive the legs of the gusset plates P, Q, the adjoining edges of the plates and angles being then welded together as indicated by weld areas 43, 44. The other leg or legs of the gusset plates may be welded at 45, 46, as herein described, to a principal member, formed by members U, V. These mem bers may be held together by a clip W which is welded to their lateral edges, as at 47 48.

The term gusset plate as herein broadly employed includes stress-transferring inserts of var ing thickness and form which project outi e the margin of the member for the attachment of sub-members. In the foregoing examples, the gusset plates preferably consist of flat steel sheets provided with straight edges butt welded to the edges of the recesses in the shapes to be joined, but it will be understood that various types of interfitting meeting edges in the members and plates may be employed. In Fig. 7 various shapes of angular and circular interfittmg edges are indicated; Fig. 8 illustrates a shouldered joint; Fig. 9 illustrates a triangular keyed joint; and Fig. 10 a circular keyed joint. While the butt welds employed comprise metal deposited by fusing sultable metallic material or welding rod by high-temperature heating means, such as an oxy-acetylene flame or an electric are, or in accordance with the high-temperature brazing method disclosed in U. S. Patent No. 1,620,324 granted to Glenn 0. Carter, March 8, 1927, the term Welding as herein used comprises these and equivalent welding methods which may be employed. The herein described improvements are applicable in joining various structural shapes and other members, and numerous changes may be made in the details herein disclosed without departing from the principles of this invention or sacrificing its advantages.

I claim:

1. A method of joining structural members that comprises removing portions of such members, inserting portions of a gusset plate in place of such removed portions, and weldirig edges of said members to edges of said p ate.

2. A method of joining structural shapes that comprises removing portions of such shapes disposed in the same plane, inserting portions of a gusset plate to replace such removed portions, and Welding together the opposed edges of said plate and said shapes.

3. A method of joining structural members having legs that comprises removing portions of said legs to leave recesses in the edges thereof, disposing such recessed legs in the same plane and in opposed relation, providing a gusset plate having legs adapted to fit such recesses, inserting said gusset plate between such members with the legs thereof fitted into said recesses and replacing such removed portions, and welding together said plate and said members along the edges of said recesses.

4. A method of joining members having angularly disposed legs that comprises removing a portion of one leg of each member, providing a gusset plate having portions adapted to replacesuch removed portions, inserting said plate between said members so as to replace the removed portions of the latter, and Welding edges of said plate to the legs of each member.

5. A joint of symmetrical section comprising a plurality of structural members aving portions thereof disposed in the same plane. and a stress-transferring posed in said plane and united to said mem: bers, the position of said plate being such that said joint is symmetrically stressed both in tension and in compression.

plate dis- 6. A joint as claimed in claim 5 wherein said members and said plate have interfittmg portions keying them together.

7. A joint comprising a plurality of structural shapes having portions thereof disposed in the same plane, and a gusset plate disposed in said plane between said shapes, said plate being symmetrically positioned with respect to the principal plane through the structure containing said joint'and having edges thereof butt-welded to said shapes.

8. A joint as claimed in claim 7 wherein said shapes comprise certain portions perpendicular to and other portions coextensive with ortions of said plate,

9. joint comprising a plurality of structural shapes having recessed portions thereof disposed in the same plane, and a gusset plate disposed in said plane and having legs fitting into such recesses and butt-welded to the edges of such recesses.

10. A built-up metallic structure comprising main and sub metallic members consisting of rolled structural shapes, such members having portions thereof removed; and gusset plates inserted between and welded to said members and replacing the removed portions thereof.

11. A gusset plate having means along its edges adapting it to be interlocked or keyed to a structural member.

12. A rolled structural shape comprising an angle having one leg projecting longitudinally beyond the other leg, a gusset plate Welded to the end edge of the shorter leg and to the longitudinal edge of the other leg.

13. A rolled structural shape having two or more parallel legs, one of which is longer than the other or others, and a gusset plate Welded to the ends of the shorter leg or legs and to a longitudinal edge of the longer leg.

14. The combination with two structural members disposed back to back, of one or more gusset plates welded to adjoining portions of said members and to one another.

15. The combination with two rolled structural shapes comprising angles disposed back to back, of a gusset plate welded to longitudinal and transverse edges of each of said angles.

16. The combination with two rolled structural shapes disposed back to back having corresponding portions thereof removed, and gusset plates replacing such removed portions and united to said shapes by longitudinal and transverse welds.

17. A built-up metallic structure comprising a plurality of metallic members having recesses therein in the principal plane of the structure; and means joining said mem-- hers, such means comprising stress-transferring members disposed in said plane, fitting said recesses, and welded to the edges of the latter.

18. A built-up metallic truss comprising main members and sub members, such members havin recesses therein in the princi a1 plane of the structure; and stress-trans erring plates joining such sub members to said 5 main members, such plates being disposed in said plane and having portions dis osed in said recesses and welded to the edges in ereof, as and for the purpose described.

In testimony whereof, I afiix my signasure.

HERBERT H. MOSS.

Images