US1885861A - Method of making rails - Google Patents

Description

Nov. 1, 1932 H, RYDIN 1,885,861

METHOD OF MAKING RAILS- Filed Aug. 15, 1929 3 Sheets-Sheet 1 y w T f y N.'-1.C3 NFZD M mo M940 6 B wag m s-U //Y- 14 NF'ZO N?-8.U

Inventor Attorney' Nov. 1, 1932. H, c, RYDlNG 1,885,861

METHOD OF MAKING RAILS Filed Aug. 15, 1929 5 Sheets-Sheet 2 fiy In ven for A; A Hartley Nov. 1, 1932.

H. C. RYDING METHOD OF MAKING RAILS Filed Aug. 15, 1929 3 Sheets-Sheet 5 Lila 102 Inventor ,5 Attorneys Patented Nov. l, 1932 UNITED STATES HERBERT C. RYDING, OF BIRMINGHAM, ALABAMA manner or MAKING mus Application filed August 15, 1929. Serial No. 386,214.

provided with-a fluted or corrugated outer surface.

The inventionand advantages arising from the practice thereof will be fully apparent from the following specification when read in connection with the accompanying drawings. In the drawings Fig. 1- 'is a diagrammatic view illustrating in condensed form certain steps of my improved method;

Fig. 2 is a longitudinal section through an ingot mold suitable for use in casting ingots to be used in my method;

Fig. 3 is a cross section on line 33 of Fig. 2;

Fig. 4 is an elevation of an ingot made in the mold of Figs. 2 and 3;

Fig. 5 is a cross section of the ingot taken on line 55 of Fig. 4;

Fig. 6 is a perspective view of a slightly modified form of ingot adapted for use in the method;

Fig.7 is a diagrammatic view illustrating diflerent passes to which the in ot is subjected in carrying out my metho Fig. 8 is an elevation of a pair of coacting rolls adapted for rolling an ingot into bloom; Fig. 9 is an elevation of a pair of roughing rolls adapted to roll a bloom approximately to the desired shape; I

Fi 10 is an end view illustrating rolls of a three-high edging mill; r Fig. 11 is a similar view illustrating another set of three rolls of an edging mill;

Fig. 12 is a view of a pair of coacting rolls of a rolling mill adapted to produce a rail of the desired-cross sectional contour.

Heretofore in the rolling of rails, I-beams,

H-sections and various other rolled sections, it has been .almost a universal practice to start operations with the production of an' -cally at C so as to produce a substantially ingot ofrectangular shape in'cross section having slightly rounded corner portions.

There have been cases where others have proposed to cast grooved ingots roughly approximating the shape of the finished rolled 5 product. Round ingots have been previously made but as far as I am aware they have never been used for the production of rails, I-beams or other flanged sections. In practice ingots of round or substantially circular cross section have, so far as I am aware, been used only for. the rolling of plates, slabs and similar non-flanged members.

It has been generally thought by those skilled in the art that ingots of substantially circular cross section were wholly unsuited for use in rolling rails and similar flanged sections, the opinion held by many skilled in the art being that because the finished flanged sections such as rails, I-beams and the like usually had flange and web portions disposed perpendicularly to one another, that it was desirable to start with an ingot such as a rectangular ingot having faces, which' were substantially perpendicular to one another.

I believe that I am the first to discover and point out the advantages of producing rails and similar rolled structural sections from round fluted ingots and am quite confi dent that I am the first to have actually practiced such a method of producing rails.

My improved method is illustrated very. diagrammatically in condensed form in Fig.

- 1 wherein A represents a substantially round or approximately cylindrical ingot, which is fed through several passes, through rolls B of a blooming mill indicated diagrammatirectangular bloom indicated at D.

The bloom D is then subjected to rolling treatment between the rolls E, of a rollingmill F, which are effective to work the rail so as to produce a rail G of the desired cross sectional shape.

Referring more in detail to the several steps followed in carrying out my method, I first form an ingot by teeming molten steel from a suitable ladle into an ingot mold H 100 ment in a rolling mill so as to produce a rail 1 These passes prepare the bloom for follow- 5 stantially the form shown in Figs. 4 and 5,

this ingot being substantially or approximately circular in cross section and having a fluted or corrugated surface as indicated at a.

The ingot after being stripped from the mold is introduced into a soaking pit where it is brought to a proper temperature for rolling. The reheating treatment in the soak-- ing pit equalizes the temperature of the ingot and because of the fact that the ingot is substantially circular all parts thereof are brought to a uniform temperature. Unlike a rectangular ingot, a round ingot is cornerless. Therefore when the round ingot is withdrawn from the ingot mold any cooling thereof will be uniform throughout the body structure of the ingot. On the other hand, with the rectangular ingot heretofore used the corners having relatively lessmetal than other parts of the ingot, have a tendency to cool more rapidly than other portions.

The round fluted ingot after reheating is removed from the soaking pit by suitable overhead tackle and is transferred to a blooming mill wherein it is subjected to a multiplicity of passes through rolls of the character' illustrated in Fig. 8. In this figure, 30 and 32 represent the rolls of the mill and the spaces 34, 36, 38 and 40 represent the socalled passes of the mill. The substantially circular ingot is rolled first through the pass 34 so as to form an approximately rectangw lar bloom, which is in turn passed through the passes 36, 38 and 40. In these passes the bloom is worked and alternately changed in shape. Fig. 7 is a diagram showing the shape, which the bloom assumes in 25 different passes through the blooming mill, the

different passes being numbered from 1 to 25 inclusive. Between passes the bloom'is turned by suitable manipulators in a manner knownin the art.

After the substantially round ingot has been subjected to rolling treatment in a blooming mill, its final cross sectional shape is substantially square or rectangular. This transformed body of metal is of course greatly elongated in the rolling treatment in the blooming mill and this piece of metal thus worked is known in the art as a bloom. The rectangular bloom is now subjected to treatof the desired cross section.

. In the first stages of rolling, the "bloom is passed successively through the passes 42, 44 and 46 of the rolls 48 and 50 of Fig. 9.

ing passes 48 and 50, which roughly roll the metal to approximately the desired sectional contour.

i Further treatment includes rolling between the passes of rolls 52, 54 and 56 as shown in Fig. 10. In the passes 58, 60, 62 and 64 the head of the rail and flanges are chiefly subjected to rolling. In the subsequent passes 66, 68, and 72 the edges of the head are rolled as are also the base flanges of the rail.

Further rolling treatment is effected between the rolls 74:, 76 and 78, the rail being passed through the passes indicated at 80, 82, 84, 86, 88, 90, 92 and 94. After this rolling treatment through the mill rolls of Fig. 11 the rail is subjected to rolling treatment between the finishing rolls 96 and 98 of Fig. 12 by rolling through the passes 100 and 102, which produce a rail of the desired cross sectional contour.

In the rolling of rails from ingots, it is necessary to have the ingot asfree as possible from all surface defects or irregularities and as free as possible from interior strains, and of as even a heat throughout all portions of the ingot as possible; and to roll the ingot through the necessary number of passes into the finished section with the maximum conservation of uniform heat in all portions of the section. It is also desirable that there be the least possible tendency for the formation of surface flaws or defects so that the surface of the finished rail will be smooth and free 'fromsurface irregulari- These The advantages of using round fluted in- I gots in rail making over the use of rectangular ingots heretofore used in rail making are as follows 1. The uniform ty of solidification in round fluted ingots gives less structural weakness as compared with the rectangular ingots; this is due entirely to the elimination of the corners of the rectangular ingots and to the consequent elimination of the cooling strains which are inherent in the rectangular ingots. This uniformity of structure of the material in the ingot is reflected in the improved structure of the steel in the finished rail.

2. When-the round fluted ingot is stripped, it is found to be ata more uniform temperature throughout than is tliecase with the rectangular ingot. The round fluted ingot is charged, therefore, into the soaking pits at a more uniform temperature throughout varying dimensions, as is the case with the rectangular ingot. The round fluted ingot is brought to the rolling temperature more rapidly and with less danger of local overcharging of the ingot into the soaking pits.

4. As a result of the reduced rate of cooling of the round fluted ingot, as compared with the rectangular ingot, shorter firing pe riods and longer soaking periods are possible in bringing the round fluted ingot up to the necessary rolling temperature for the production of rails than is possible with the rectangular ingot.

5. The greater uniformity of heat throughout the round fluted ingot, as compared with the lesser uniformity of heat throughout the rectangular ingot, results in practically eliminating the tendency for the formation of tears, which are caused-by variations in the rate of flow of metal during the rolling proc- 1 ess, due to variations in temperature and,

therefore, in the degree of plasticity of surface metal.

6. The surface, or skin, of cast steel ingots is relatively weak or tender and is, therefore, easily torn when stressed as in rolling.

The round fluted ingot, as a result of the contour of cross-section, is subjected to more work on the surface on account of the necessity for squaring the ingot in the early stages of the rolling than takes place with the rectangular ingot. This greater amount of work and more equal distribution of work in the initial stages of rolling results in a reduction of cross-sectional area at a greater rate than the elongation, which greatly minimizes the tendency to the formation of surface cracks or tears in the initial passes. It

has been found in actual practice in the rolling of rails from round fluted ingots, that the small seams occurring in the head and base of rails as usually fabricated, have been largely eliminated.

7. The advantages of the light drafts and the frequent turns in the blooming mill rolls and, therefore, the advantage of the additlonal passes inthe blooming mill, is shown in the diagram of the blooming mill rolls and'outlines of passes in Fig. 8. The first pass in the blooming mill rolls 30, and 32 has the sides 35 of the pass 34: on an angle, which tends to eliminate the possibility of lap formation while the ingot is being squared.

8. To maintain the advantages obtained from the round fluted ingot as rolled in the blooming mill, the arrangement shown in Fig. 9 for the roughing mill passes is preferable. This arrangement maintains the initially good surfaces as received from the blooming mill and reduces or eliminates the tendency for seam of lap formations during the roughing passes.

9. The greatest advantage theround fluted ingot has over the rectangular ingot from which to roll rails, is the absence of the corners which are responsible for, in the case of rectangular'ingotsless uniformity in the structure of the ingot, less uniformity of the distribution of heat in the heating process and the work in the rolls, particularly in the early passes in the blooming mill, is so changed in the case of round fluted ingots as to tend to heal up defects rather than aggravate defects as is the case in rolling rails from rectangular ingots.

10. Round fluted 'ngots are more suitable for rail fabrication than the rectangular ingotsheretofore used due to the elimination of the corners, the more even temperature of the round ingot, and the better distribution of work with lighter initial drafts in the bloom"- ing rolls, which produces a rail substantially free from surface defects.

11. The use of round ingots in rolling rails overcomes the disadvantages whichare inherent in the rectangular ingots which disadvantages are due largely to the corners of the rectangular ingots cooling more rapidly than other parts of such rectangular ingot.

While I have described quite specifically the definite sequence of steps carrled out in following my method and'have illustrated a fluted ingot and rolls of definite shape it is not to be construed that I am limited thereto. The drawings and description are to be interpreted in an illustrative rather than a limiting sense.

\ What I claim is:

' 1. In the manufacture of rails the method which consists in providin a fluted ingot which is substantially circu ar in cross sevtion, reheating the ingot and subjecting it to a number of passes in a blooming mill to form a bloom of substantially rectangular cross section and subjecting said bloom to a number of passes in a rolling mill to produce a rail of the desired cross sectional contour.

I 2. In the manufacture of rails the method which includes providing a cornerless ingot, subjecting the ingot to rolling to form a substantially rectangular bloom and subjecting said bloom to rolling to produce a rail of the desired cross sectional contour.

'3. In the manufacture of rails the method which includesproviding an ingot'which is substantially or approximately circular in cross section, rolling the ingot into a bloom and subjecting said bloom to further rolling to produce a rail of the desired cross sectional contour.

4. In the art of manufacturin rails, the method which includes casting a su stantially circular ingot of such cross sectional shape that in any given quadrant thereof a substantial surface of the ingot corresponds in outline to a circle, subjecting such ingot to a number of passes in a blooming mill to form a bloom of substantially rectangular cross section,'then subjecting the bloom to a number of passes in a rolling mill to produce a rail of the desired cross sectional contour.

5; In the manufacture of rails, the method which comprises providing a substantially round ingot, any quadrant of which has a plurality of longitudinally extending flutes,

the outer extremities of which may be said to be circumscribed by a circle, subjecting such ingot to a rolling operation'to form a sub-- stantially rectangular bloom and then subjecting the bloom to further. rolling opera- 7 tions to produce a rail of the desired cross sectional contour.

In witness whereof, I have hereunto signed my name.

HERBERT c. RYDING.

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