US1132052A - Method of making welded rail-joints. - Google Patents

Description

J, WATTMANNH METHOD OF MAKING WELDED RAIL JOINTS.

APPLICATION FILED AUG. 23, 1913.

Patented Mar. 16, 1915.

I D I 2 SHEETSS HBET 1.

WITH/E8858 l/Ul/E/VTOR JOH/l/ WA THEM/WU J. WATTMANN.

METHOD OF MAKING WELDED RAIL JOINTS.

APPLIGATION FILED AUG. 23, 1913.

1,132,052. r Patent efl Mar.16,1915.

Z SHEET8SHEBT 2.

WITNESSES: INVENTOR W Bro/11v WATT/MANN final M momma E STATES Mild.

MEEIEIGD OF MAKING WELDEQ To aZZfliham it may concern:

Be it known that 1,, JO N WATTMANN, a subject of the German Emperor, and resident of Treptow, near Berlin, Germany,

have invented certain new and useful Imrovements in a Method of Making Welded hail-Joints, of which the following is a specification. In welding rai'ljoints it is desirable to lo leave'the rail heads unwelded, for the reason that the heating of themetal will always cause a change in its internal structure, thus giving the upper or'tread surface a resistance against wear different from the resistance at other points of said tread surface.

Welding the rail ends at the bases only is unsatisfactory because the rails will oppose an insufficient resistance to forces tending to ive the joint a convex upward curvature, so that the joint will open at the rail heads. Such forces come into play when the joint comes between two loaded axles, and the bending force may becomelquijte considerable, particularly when the track is constructed with cross ties. It is true the resistance against such bending stresses may be increased by welding fish-plates or jointbridging supports to the rail bases, but even then the joint will open (although to a smaller extent) whenever the rail ends are bent upward and whenever the rails contract owing to temperature changes. (if course, as soon as the joint opens, the same defects will occur (to a greater or smaller extent) which are well known in connection with all rail join'ts employing screws or wedges. "These drawbacks may be avoided by producing in the joint, during the welding operation, a permanent artificial strain of such 40 a character that the rail heads are strongly pressed against each other at the joint. in this case, tension strainssuch as occur in the rail heads when outer forces give the rails an upwardly convex curvature, will not at once cause the joint. to open, but will, at first, only reduce the inner compression strains normally existing in said rails. The joint will open only when these outer forces overcome these inner strains, so that a tension strainresults at the joint. in the same manner, contractions of the track due to temperature changes'wi'll take place Without causing the joints to open. Thus, within certain limits of stresses, which are not er:- needed in practice, the rail joints may be caused to remain closed permanwtly. wlit is Brwifl ation of Lette s Retest.

Application filed August 23, 1913.

, concurs.

Patented Mar. 16, 192 .5.

serial No. 786,338.

, well-known that these artificial compression strains can be produced by thermie means, viz., by'cooling the parts which are heated uneven 1v durin the weldin operation. This method 0 welding railoints, while correct in principle, is ob ectionable in practice, first, on account of the difiicu lzty and almost impossibility of ob-tainin exactly the desired amount of internal strain, since the heating of the joint depends very largely on the sire of the weld, the time used for weldng, the order inwhich thesuccessive weldings of a joint are erformed, and so on; second, because the c oice of shapes for the oint-bridging support is restricted, since the heating of the support, as regards conduction and radiation, is governed by the form of its cross section and of its surface.

According to my present invention an arti'ficia l internal combustion strain is produced at the joint portion of the rail heads by bending (within the elastic limit) either the -rail or the joint-bridging support, or both, hymec'hanical means such as screws, wedges, etc, and welding the parts together while they are thus bent or deformed.

The invention is applicable, broadly, to constructions 1n which a j oi-nt-brid gin-g memher is Welded to meeting rail ends, whether such member he a support proper extending under the rail 'bases, or a laterally-applied fishsplate. I V

The advantage of my invention resides in v the :fact that the outer forces applied to the oint 1n order to produce the internal strain, maybe exactly predetermined, that is to say, the exact amount of internal strain desired may be obtained with certainty. Further, the j oint-brid'eing member may 'be given any shape desired, provided, of course, it has the requisite strength. Itis preferable to lay the rail joints and oint bridging members before the bending operation, so that the raii endswill resume their horizontal position at the end of the welding operation. i

"In the accompanying drawings, i have shown, in side elevation, several diiieren't wavs of c'arrving out 'mv invention, Figures 1 to 4 illustrating the use of a support extending under the rail bases, while Figs. 5 to'8 show theme of fish-plates; 1 is a sideelewiation of one form of my inventidn at an intermediate stage, and Fig. ,2 shows the sameform at its final stage: Figs. 3 and 4 each illustrate another form oi my in-v'enfiected upward at the joint as indicated by full lines. Then, by means of any suitable I tion;

' given to the rails and to the bridging members has been exaggerated, for the sake of clearness. i

' In Fig. 1 it has been assumed thatthe ends of the'rails a have been brought together as close as possible and then the rail ends have I been connected with each other at their bases I and with the joint-bridging support I) by welding metal 8. This support I; may be a piece of rail resting on two cross-ties (not shown). Wedges k tapering transversely of the rails are then driven between the rail bases and theends of the support 6 so as to force the support away from the rail bases at both ends. Fig. 2-shows that this forcing apart of the rails a and support Z) bends the bridging support Z") upward and the railsa downward so as to produce a compression strain atthe joint surfaces of the rail heads. The joint is completed by welding the wedges is to the rails a and to the support 6.

According to Fig. 3'the ends of the bridging support I) are firstwelded to the rails a, as indicated at c, the rails being bent or depressure device, such as the bow c3 and screw 6. the rails are bent down to the position inv dicated by dotted lines, which also forces the ends of the rail heads against each other so "as to produce a long tudinal compression strain in said heads. Then the central portion or jointproper is Welded, as at f, to

connect the endsof the rail bases with the support Z). Upon removing the press 0?, e, *L. rails a spring back into the alining posi-.

tion shown in Fig. 2, while at the same'time the support 6 assumes the upwardly convex shape shown in said Fig. 2. all owing to the elasticity of the rails a and the support Z).

- According to Fig. 4:, the ends of the support 6 are first welded to the rails a, which are deflected upward in the same manner as in Fig. 3. I then apply a press consisting of a'bow d. which engages the central portion of the support I; from below, and

screws 6' engaging therails a; from above at points corresponding to the ends of the support. nvturning the screws e to force them down in the bow d, the support 6 is bent into the upwardly convex shape indicated by dotted lines, and with the parts in this position, the central weld f is made. The press having been removed, the sins ticity of the support Z) will cause it to pull or bend the rails a down into alining position. so that the final shape of the completed joint is as in Fig. 2. V

In 5 to 8, the joint-bridging member is nota support extending under the rail bases, but a laterally arranged fish-plate g. According to Fig. 5, the rails 11, held in contact and deflected upwardly as in Fig. 1, are

' first welded at the adjacent ends of their bases, to the central portion of the fish-plate Then wedges 7c are driven between the ends of the fish-plate and the adjacent portions of the rail heads, thereby bending the said fish-plate into an upwardly convex shape, and bringing the rails into the alining position as shown in Fig. 6. T hereupou the joint isfinished by welding the ends of the fish-plate to the rail bases, as indicated at l lccording to Figs-7 and 8 the ends of the fish-plate g are first welded to the rail bases as at 7*, and then, by driving a wedge is between the central portion of the fishplate and the meeting ends of the rail bases, the. rails and the fish-plate are brought from the original position (Fig. 7 to the final position, Fig. 8, in which the 'aliningrail ends are subjected to, an internal compression strain, which is preserved by welding the wedge to the fish-plate and to the abutting rail bases. 7 j i In all forms of my invention,"the heads of the alining rail ends, welded to the jointbridging member, are normally under an internal compression 'straimthe magnitude of which may be determined exactly during the making of the joint. The welding operation. is preferably performed electrically.

Variousmodifications may be made without departing from the nature of my invention as set forth in the appended claims.

1 claim:

1. The method of. welding rail joints, which comprises placing 'a joint-bridging -member adjacent to the railends, then applying mechanical means to produce a relative elastic bending between rails and said member, to produce an internal compression strain in the rail heads, and then Welding said member to the rails.v

2. The method of welding rail joints, which comprises placing a joint-bridging member. adjacent to the rail ends, welding the central portion of the said member to the rail bases and at the same time welding the ends of the rail bases to each other, their driving the ends of the joint-bridging member away from adjacent portions of the rails, by mechanical means, and finally securing the ends of the joint-bridging meme,

her to the rails in this strained position.

3. The method of welding rail joints which comprises placing a joint-bridging to each of the rails at points separated from 'the first named welding points.

4. The method of welding rail joints which comprises placing a joint-bridging member adjacent to the rail ends and welding said member to each rail at the rail ends and to at least two other separated points, said member and the rails being elastically bent with reference to one another, so as to 10 have an internal compression strain in the rail heads, when the last of said Welds is made.

, In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

JOHN WATTMANN.

Witnesses:

v HENRY HASPER,

HARRY L. WILSON.

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