US1450935A

US1450935A - Permanent joint in fabricated form and method of maxing the same

Info

Publication number: US1450935A
Application number: US266407A
Authority: US
Inventors: James L Anderson
Original assignee: Air Reduction Co Inc
Current assignee: Airco Inc
Priority date: 1918-12-12
Filing date: 1918-12-12
Publication date: 1923-04-10
Anticipated expiration: 1940-04-10

Description

Apr. W, 11923. 1,45@,935

J. ANDERSON PERMANENT JOINT IN FABRICATED FORM AND METHOD OF MAKING THE SAME Filed D60. 12, 1918 2 sheets-sheet 1 IAH/ENTOR BV ATTORIIIE;

Apr; M1 1923.

J. L. ANDERSON PERMANENT JOINT IN FABRICATED FORM AND METHOD OF MAKING THE SAME 2 sheets-sheet 2 Filed Dec. 12, 1918 @TATES @FFHCE.

JAMES L. ANDERSON, OF BAYONNE, NEW JERSEY, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO AIR REDUCTION COMPANY, INCORPORATED, OF NEW YORK, N. Y.,

A CORPORATION OF NEW YORK.

PERMANENT JOINT IN EABRICATED FORM AND METHOD OF MAKING THE SAME.

Application filed December 12, 1918. Serial No. 266,407.

I '0 all whom it may concern:

Be it known that I, JAMns L. ANDERSON, a citizen of the United States, and resident of Bayonne, in the county of Hudson and State of New Jersey, have invented new and useful Improvements in Permanent Joints in Fabricated Forms and Methods of Making the Same, of which the following is a specification.

The object of the invention is to enable plates and other fabricated forms, of steel or other ductile metal, to be united integrally, without difiiculty in the process due to expansion or contraction, and without the 5 existence of strains in the completed work likely to result in after rupture either in or out of the weld. The invention makes it possible, for example, to weld ship plates successfully, and 1s equally "applicable in other cases. The preferred manner of practising the invention will noW be briefly described, with illustrations of certain of its applications.

In the drawings:

Figure 1 is a plan or elevation showing portions of a number of adjoining plates and illustrating various stages of the process of uniting them;

Fig. 2 is a cross-section through the completed weld;

Fig. 3 illustrates the application of the invention to uniting the ends of cylindrical tubularsections; and

.Fig. 4: illustrates its application to the longitudinal seam of a tubular section or body. V

In Fig. 1 rectangular plates a, a (1?, a are to be united at their edges, without lapping and without riveting. They may form partof the outer fabric of a ship or of some other structure, and may be either flat on curved. In accordance with the invention the edges of the plates, instead of being straight, are provided with interfit- 5 ting formations, especially regular indentations the sides of which are inclined at angles of to the general direction of the joint. forming series of tapering triangular projections and recesses which match 0 when the plates are juxtaposed in predetermined manner, to form a saw-toothed seam composed of alternating reverse diagonals crossing the neutral or median general direction line. The edges are also beveled at approximately 45 to the surface, so that when the plates are put together a zig-zag trough is formed.

The joint between two plates, for example a and a is fused, with an oxyacetylene or other blowpipe flame or with the electric arc, with addition of metal, at some selected spot I), so that the seam is tacked. The spot would be substantially midway of one of the diagonal sections of the indented seam, and its extent lengthwise of the seam should be approximately as great as the width of the trough at the top. The seam may be regarded as composed of alternating right-hand and left-hand slopes or diagonals, forming the sides of the projections or recesses. The spot Z) is illustrated as located upon one of the right-hand sides. At the same time that the seam is being tacked at this point, or subsequently, and before it is tacked upon another corresponding side,

it is fused at a spot 6 midway of a lefthand side. The two tackings may be near together or far apart,"depending upon work ing conditions. Thereafter the remaining sides or slopes are similarly tacked at intermediate points, this stage being illustrated in the portion of the seam between the plates a and a The first two tack welds being at reverse sides, their contraction stresses oppose each other and the distortion or displacement effects are therefore neutralized. The subsequent tackings may also be, performed in such order as to balance, but this is not as important as with the first tackings. If desired, the seam could be tacked simultaneously at more than two points in the first instance, the locations being such as to balance.

The seam has now been tacked upon opposite sides of each projection, or in other words, where the diagonals cross the neutral or center line of the seam. As indicated by dotted lines as, this leaves in both edges relatively narrow free tongues d opposed by relatively wide areas 8 across the seam. Upon now welding the bent or it-shaped seam-section included between two of the tack welds, this section of the weld, being of large extent relatively to the tongue, becomes, as it were. assimilated to the area 6 and the contraction strains are thrown largely upon the tongue 03, which being ductile is capable of elongation. The same is true in respect to the welding of all these sections. In this way rupture of the weld While setting, or subsequently, due to contraction strains, is avoided, these strains being taken by the ductile tongues alternately at opposite sides of the neutral line of the seam. Owing to the form of the oint and the manner in which the weld is efiected. the contraction strains taken from the weld and applied to the original metal never exceed or dangerously approach the limit of tensile strength of the metal, as may be the case with other procedures. By the multiple diagonal zigzag weld the stresses that are produced are so varied that there is no possibility of a concentration of stress in any one direction, which would be troublesome. Finally, as will now appear the remaining stresses can be relieved by reheating, without subjecting other portions of the weld to compression stresses, which in turn would become tension stresses when cool.

In order further to relieve the weld of contraction while setting. that is to say the angular sections between the tackings, it is desirable to reheat the body of the metal by the flame or otherwise opposite the sections,

approximately at the regions enclosed by the dotted lines 3 This urges the metal toward the weld and protects the same until it has become permanent.

A. complete joint is indicated between the plates a a and in section in Fig. 2. The actual melting of the bottom and sides of the trough and the manipulation of the molten metal will follow accepted autogenous or electric welding practice. The weld is filled in the regular manner by adding similar or dissimilar metal from a rod held in the blowpipe flame, in the case of flame welding, or from a rod held in the arc, if the seam is welded electrically, or from the material of the electrode itself. The finished joint is not only substantially relieved of contraction strains, but is also stronger for all purposes than a straight joint, being composed of multiple diagonal sections running in both directions. Effectively, such a weld is stronger than the original metal.

Making permanent joints in other fabricated forms does not differ materially-from the case of plates. Figs. 3 and 4 show joints in readiness for welding.

The method may be used with advantage for uniting either similar or dissimilar metals.

What I claim as new is:

1. The method of obtaining permanent butt joints in fabricated forms, which comprises providing the parts to be united with interfitting indented edges consisting of tapering, substantially triangular projections and alternating recesses, and uniting said edges by fusion. whereby a saw-toothed welded joint is obtained consisting of multiple diagonals running in alternately angularly related directions across the neutral or center line of the seam. v

Q. The method of obtaining permanent butt joints in fabricated forms, which comprises providing the parts to be united with interfitting in'dented edges consisting of tapering. substantially triangular projections and alternating recesses the sides of which are substantially to, the general direction of the joint, and uniting said edges by fusion, whereby a saw-toothed welded joint is obtained consisting of multiple diagonals running in alternately angularly relateddirections across the neutral or center line of the seam.

3. The method of obtaining permanent butt joints in fabricated forms, which comprises providing the parts to be united with interfitting indented edges consisting of tapering, substantially triangular projections and alternating recesses, which when matched form a saw-toothed seam composed of diagonals running in alternately angularly related directions across the neutral or center line. of the seam, tacking the matched edges by fusion substantially midway of the diagonals along the neutral or center line of the seam, and thereafter tusing the edges together throughout the remainder of their extent.

4. The method of obtaining permanent butt joints in fabricated forms, which comprises providing the parts to be united with inte-rfitting indented edges consisting of tapering, substantially triangular projections and alternating recesses, which when matched form asaw-toothedseam composed of diagonals running in alternately angularly related directions across the neutral or center line of the seam tacking the matched edges at two or more initial points. substantlally midway of reversed diagonals,

so that the strainsbalance and the parts are held in proper relation, then tacking the other diagonals at approximately their middle points, along the neutral or center line of the seam, and finally completing the welding of the seam.

5. The method of obtaining permanent butt joints in fabricated forms, which comprises providing the edges of the parts to be united with interfitting tapering projections and recesses having diagonal sides, matching the edges, tacking the crooked seam by fusion at intermediate regions at the diagonals, and thereafter completing the welding of the seam.

6. The' method of obtaining permanent butt joints in fabricated forms, which comprises providing the edges of the parts to be united with interfitting tapering projections and recesses haying diagonal sides, matching the edges, tacking the crooked seam by fusion at intermediate regions of the diagonals, thereafter welding the crooked or V-shaped seam portions between said re .gions, and reheating the body of the metal opposite said crooked seam portions before the same have set.

7. The method of obtaining permanent butt joints in fabricated forms, which comprises providing the parts to be united with beveled and dia onally indented edges, matching said edges, tacking them by fusion at the regions along the neutral or center line of the seam, and thereafter completing the welding of the sea-m with addition of metal.

8. In the production of a permanent butt joint between fabricated form portions, the steps which comprise juxtaposing two edges of interfitting formation to form an indented seam, tacking said seam at the intermediate regions of the indentations, and thereafter welding the crooked seam sections between said regions.

9. In the production of a permanent butt joint between fabricated form portions, the steps which comprise juxtaposing two edges of interfitting formation to form an indented seam, tacking said'seam at the intermediate regions of the indentations, thereafter welding the crooked seam sections between said regions, and reheating the body ing of the seam by fusion with addition of metal.

11. A permanent butt joint comprising indented edges composed of tapering projections and intervening recesses matched and fused together in a welded seam composed of diagonals alternately reversely inclined to the neutral or center line of the seam.

12. A permanent butt joint comprising indented matched edges fused together in a substantially saw-toothed welded seam composed of diagonals alternately clined at approximately or center line of the seam.

13. A fabricated structure comprising plates having saw-toothed edges interfitted and fused together, presenting a welded seam substantially all portions of which are diagonal to the i'general direction of the seam.

JAMES L. ANDERSON.

reyersely into the neutral