US2972916A - Rolling mill drive - Google Patents

Description

Feb. 28, 1961 M. MORGAN ROLLING MILL DRIVE Filed June 15, 1958 INVENTOR. MYLES 'MoR GAN Feb. 28, 1961 M. MORGAN 2,972,916

ROLLING MILL DRIVE Filed June 13, 1958 8 Sheets-Sheet 2 HE-V221: l v-Lm 'ZH- VERT- 1YVERT.

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- INVENTORQ MYLES M ORGAN mm ma ATTORNEY v Feb. 28, 1961 M. MORGAN ROLLING MILL DRIVE Filed June 15, 1958 8 Sheets-Sheet 3 #9, -\o gow;gomm 2020M E MWHENQTMH mHsLHw fin H .H H W E w w mm 2020M a. .H. H

E. HUN. SHE. E. 5 W

ATTORNEY Feb. 28, 1961 M. MORGAN 2,972,916

ROLLING MILL DRIVE Filed June 13, 1958 8 Sheets-Sheet 5 INVENTOR. 772 I l e s 771 0 T5! an Feb. 28, 1961 M. MORGAN 2,972,916

ROLLING MILL DRIVE Filed June 13, 1958 8-Sheets-Sheet 6 INVENTOR. 772 yZ es mo 'rgan H or ey Feb. 28, 1961 M. MORGAN 2 972,91

' ROLLING MILL DRIVE Filed June 13, 1958 8 Sheets-Sheet 7 INVENTOR. 777 yZ e s m organ ROLLING MILL DRIVE Myles Morgan, Worcester, Mass, assignor to Morgan Construction Company, Worcester, Mass, a corporation of Massachusetts Filed June 13, 1958, Ser. No. 741,970

2 Claims. (CI. 80-54) This invention relates to a rolling mill and more particularly to an arrangement of steel mill apparatus for producing a large variety of shapes and sizes of rolled metal. This is a continuation in part of patent application S.N. 387,848, filed October 23, 1953, now abandoned.

In many steel mills it is desirable to be able to roll from a billet to any of a number of shapes and sizes of finished product. Such products as rod, angles, strip and bar are very dillicult to produce on a single mill, since each is a specialty in itself. In the past these products have been rolled on a. single mill, but the changes required to convert the mill from one product to any other were quite extensive and time-consuming. Also, when such a method of operation was attempted, it was discovered that compromises had to be made to suit all conditions. If, for example, the mill was designed to operate very well in rolling narrow strip or skelp, it was necessary in rolling bar to twist the material being rolled after practically every roll stand. When it was desired to roll bar double-strand on such a prior art strip mill, the obstacles were insurmountable. These difiiculties of the mills of the past are obviated in a novel manner by the present invention.

It is therefore an outstanding object of the present in vention to provide a rolling mill that will produce a variety of products.

Another object of the invention is the provision of a rolling mill that can produce rod, strip, angles and bar with a minimum of twisting.

A still further object of the instant invention is the provision of a rolling mill which not only will produce a variety of products, but which will roll bar doublestrand with a minimum of twisting.

It is a further object of the invention to provide a rolling mill which will produce high quality rod, angles, strip and bar with equal facility.

Another object of the invention is the provision of a rolling mill which can be changed with a minimum of down-time to roll an entirely different product.

A further object of the invention is the provision of an arrangement of roll stands which will permit selective rolling of either rod, angles, strip, bar, or bar double strand without difliculties due to setup time or multiple twisting.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features herein after fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

2,972,916 Patented Feb. 28, 196-1 In said annexed drawings:

Figure 1 is a plan view of an arrangement of steel mill apparatus embodying the present invention.

Figure 2 is an enlarged view of a portion of the arrangement shown in Figure 1, showing an arrangement of roll stands,

Figure 3 is a more or less schematic showing of a roll pass arrangement which may be used in conjunction with the invention for rolling small rod,

Figure 4 is a roll pass arrangement for rolling precision merchant bar without twisting,

Figure 5 is a roll pass arrangement for rolling strip or skelp,

Figure 6 is a roll pass arrangement for rolling angles,

Figure 7 is a roll pass arrangement for rolling merchant bars double strand where precision rolling is not necessary.

Figure 8 is a plan view of a drive associated with a vertical roll stand,

Figure 9 is an elevational view, partly sectioned, of the drive, and

Figures 10 and 11 are elevational views, partly sectioned, of the vertical roll stand under two conditions of operation.

Like reference characters denote similar parts in the several figures of the drawings.

Referring first to Figure 1, wherein is best shown the general arrangement of the apparatus, the rolling mill, indicated generally by the reference numeral 10, is shown as comprising a billet heating furnace Ill, a series of roll stands, a shear S, and reels 12. The roll stands are numbored, in accordance with the usual practice, 0, I, II, II-vert, III, IV, IV-vert., V, VI, VI-vert., VII, VII-vert., VIII, VIII-verL, IX, X, XI, and XII. All the roll stands are two-high horizontals, except II-vert., IV-vert., VI-vert., VII-vert., and VIII-vert., which are vertical stands which are capable of performing the dual functions of edging and rolling. Stands 0 through VI, which might be considered the roughing stands, and are aligned with each other and with the exit door of the furnace 11. These stands are followed by the shear S and by stands VII-vert. through VIII-vert., all being aligned with the exit door of the furnace and with each other. Stand VIII-vert. is followed by a horizontal looping apparatus I3 leasing to stand IX, the pass line of which is slightly inclined to and spaced from the previously-mentioned stands. A reversing table 14 is also provided between the stands VIII-vert. and IX. for the situation wherein the material is too stiif to be looped. An alternate guide 15 is provided to lead material from stand VIII-vert. to apparatus, not shown for coiling strip and the like. Stand IX is followed by a looping apparatus 16 and a reversing table 17, which are followed by stand X whose pass line is parallel to and spaced from the pass line of the stands 0 through VIII-vert. Material leaving stand X may pass to the reels 12 or may enter a runout table 18 leading to a cooling bed, not shown. In addition, a looping apparatus 19 follows stand S and leads to stand XI, which is arranged with its pass line parallel to and spaced from the previously-mentioned pass lines. Stand XI is followed by a looping apparatus 20 leading to stand XII which has its pass line parallel to and spaced from the others. While the looping apparatus 13, 16 and 19 are situated so as to lead the material away from the pass line of the initial stands, the looping apparatus 20 moves the material back toward the said pass line. This, while the pass lines of stands IX, X and XI are progressively i .be introduced into the stand IX.

reversing table 14 and be introduced into the stand IX table 17.

farther away from the pass line of the initial stands, the

the two rolls of stand are driven at the same speed,

that the two rolls of stand I are driven at the same speed,

.and that the rolls of the two stands are driven at the Stand II is driven by a motor proper relative speeds. 23 through a gear box 24. Stand II-vert. is driven by a motor 25 through a gear box 26, stand III is driven by a motor 27 through a gear box 28, and stand IV is driven by a motor 2Q through a gear box 36. Stand IV-vert. is

selectively driven by either a motor 31, of high power rating, or motor 32 of relatively low power rating; these motors driving the stand through a gear box 33 the gears of which are such that the motor 31 drives the stand at low speed, while the motor 32 drives it at high speed.

Stand V is driven through a gear box 35 by a motor 34, while stand V1 is driven by a motor 36 through a gear box 37. The shear S is driven by motor 38 through a gear box 39. Stand VI-vert. is driven selectively from a large motor 49 and a small motor 41 through a gear box 42; the gearing is such that the motor iii drives the stand at low speed while the motor 41 may be used to drive the stand at high speed. Stand VII is individuallydriven by means of a motor 43 and a gear box 44. Stand VII-vert. is connected for high or low speed operation from a motor 45 of large horsepower, a motor 46 of low horsepower, and a gear box 47. Stand VIII has its own individual motor 48 which drives the stand directly through the usual pinion housing and couplings. Stand VIII-vert. is provided with a large motor 49 and a small motor 50 which drive the stand at low or high speed, respectively, through a gear box 51.

The operation of the invention will now be understood in view of the above description. Referring to the general layout, as shown in Figure 1, it can be seen that heated billets leaving the furnace 11 can be treated in a variety of ways within the arrangement of the invention. After passing through the stands 0 to VIII-vert., the material being rolled may enter the guide and be coiled. It may also enter the looping apparatus 13 and It may also enter the without bending. After leaving the stand IX, the material may enter the looping apparatus 16 or the reversing In either case being introduced into stand X. The material leaving stand X may pass onto the runout table 18 for deposit on a cooling bed, or it may be directed into the reels 12 for immediate coiling. In addition, the material leaving stand X may enter the looping apparatus 13 and be introduced into the stand IX. It may also enter the reversing table 14 and be introduced into the stand IX without bending. After leaving the stand IX, the material may enter the looping apparatus 16or the reversing table 17, in either case being intro- .duced into stand X. The material leaving stand X may pass onto the runout table 18 for deposit on a cooling bed, or it may be directed into the reels 1 .2 for immediate coiling. In addition, the material leaving stand 'X may enter the looping apparatus 19 and be introduced into stand XI. If the latter course is taken, the material has no choice on leaving stand XI but to enter the looping apparatus 29 and be introduced into stand XII. Material leaving stand XII is led to the reels 12 for coiling.

In order to understand properly the flexibility of the present arrangement, the rolling of several types of product .will be described in connection with Figures 3 through 7. For instance, Figure 3 shows the manner in which rod may be rolled single-strand with only two twists one twist by dummying certain strands. The billet is rolled to a diamond with its axis horizontal in stand 0, the diamond is flattened further in stand I, stand II is dummied, and stand II-vert., rolls it to a square on the corner; this is flattened to a diamond in stand III, stand IV is dummied, and a square on the corner is produced in stand IV-vert. Stand V flattens it to a diamond and stand VI is dummied. Stand VI-vert. forms it into a square on the corner and stand VII flattens the material to a diamond. Stand VII-vert. converts it to a square on the corner. Stand VIII forms a diamond and VIII-vert. forms a square on the corner. The square enters stand IX on the side and is converted to an oval with the major axis horizontal. The oval is twisted to bring its axis vertical for looping and it is rolled to a square on the corner in stand X. "This is converted to an oval in stand XI, and stand XII produces the finished round. This operation would be used in producing small rounds from /2" diameter to Figure 4 shows the arrangement used to produce larger rounds in the range from "Ms" to 1%," diameter. The rod enters the reels or cooling bed directly from stand X. Otherwise, the manner of operation is very similar to that described above in connection with the rolling of small diameter rod. Stands II and IV are dummied and there is no twist between any of the stands.

Figure 5 shows the manner of operating the apparatus when it is desired to roll thin strip or skelp, starting with a billet or a slab. In this case all stands from O to VIII-vert. are. used and the product is discharged from stand VIII-vert. to the guide 15 and is eventually coiled. The horizontal stands perform the flattening operations, while the verticals are used for edging. No dummying or twisting is necessary.

Figure 6 demonstrates the use of the apparatus in rolling angles and the like. In this case no dummying or twisting is necessary and, presumably, the angle will be finish rolled in stands IX and X, making use of the reversing tables 14 and 17, and discharged onto the runout table 18 for transmission to the cooling bed. These latter steps are not shown in the drawing since the most important rolling steps take place in the stands 0 through VIII-vert.

Figure 7 shows the manner in which the apparatus may be used to roll bar double strand. In this case, the vertical stands are all dummied, and twisting is necessary. There are degree twists between stands I and II, between stands III and IV and between stands V and VI. There are 45 degree twists between stands II-vert. and III and between stands IV-vert. and V. Presumably, the bar issuing from stand VIII-vert. will continue on through stands IX and X and be transmitted to the cooling bed over the runout table 18.

It will be understood, of course, that, when the vertical stands are used for reducing a section, as they are in the operations demonstrated in Figures 3 and 4, they will be driven attheir slower speed by means of their more powerful motors. When they are used for edging, as in Figures 5 and 6, they will be driven at the faster speed through the medium of their less powerful motors. The manner in which this is accomplished can best be seen in connection with Figures 8 through ll. Figures 8 and 9 show the drive asociated with a stand IV-vertical. The large horsepower motor 31 is connected to a shaft 61 which is mounted at one end in a bearing 62 fastened to the foundation. The other end of the shaft 61 passes into the gear box 33 and has keyed thereto a small gear 63. The gear 63 meshes with a large gear 64 mounted on a stub shaft 65. One end of the shaft 65 is connected through a clutch 66 to a shaft 67 mounted in a bearing 68 which is fastened to the foundation. The clutch 66 consists of a fixed portion 69 which is fastened to the end asraere of the shaft 65 and a movable portion 71 which is keyed to the shaft 67 but is movable therealong by means of an actuating arm 72. The shaft 65 is hollow and through it extends a shaft 73 which is fixed at one end to the shaft 67 and at the other end is connected through a coupling 74 to the low horsepower motor 32.

Referring now to Fig. 10, which shows the rolling mill stand IV-vert. when used for the actual deformation of stock in the rolling of bar or the like the shaft 67 is shown as connected to a stand, indicated generally by the reference numeral 75. Attached to the inner end of the shaft 67 is a bevel gear 76 which meshes with a bevel gear 77 mounted on a vertical shaft 78. The shaft 78 is provided with a gear 79 meshing with a gear 81 having a stub shaft 82 mounted in a bearing socket 83. The shafts 78 and 82 are hollow and are provided with internallysplined surfaces in which are slidably mounted mating splined shafts 84 and 85 which are mounted parallel to one another and are capable of vertical movement relative to the foundation. Mounted in the stand 75 are rolls S6 and 87 which are connected by means of spindles 88 and 89 which spindles are in turn connected by universal couplings to the shafts 84 and 85 in the usual manner. The rolls 86 and 87 are provided with a considerable number of shallow grooves in the usual manner for use in rolling bar and rod and performing a substantial deformation thereof in the stand 75. Since the center lines of the .rolls 86 and 87 are fairly close together, the angularity of the center lines of the spindles 88 and 89 relative to the rolls and relative to the shafts 84 and 85 is quite small, so that it is possible to use long rollsand relatively short spindles.

Referring now to Fig. 11, it can be seen that the stand 75 is being .used for an edging operation by means of edging rolls 91 and 92 which are widely spaced because of the width of the sheet or skelp which they are required to edge. Furthermore, the grooves are deeply formed to keep the spindle misalignment at a minimum. The stand 75 is provided with the gear 76 which drives through the bevel gear 77 into the shaft 78, which in turn is connected to the stub shaft 82 mounted in the bearing 83 by means of the gears 79 and 81. Furthermore, the shafts 84 and 86 are slidably mounted in the hollow portions of the shafts 78 and 82 in the usual manner. However, long spindles 93 and 94 are used to connect the upper ends of the shafts 84 and 85 to the lower ends of the rolls 91 and 92. It should be noted that in this case because of the wide spacing of the rolls 91 and 92 the spindles 93 and 94 are subjected to considerable misalignment or angularity relative to the shafts 84 and 85, thus presenting a driving problem. To maintain this angle at a minimum, the rolls 9i and 92, as has been stated, are grooved as deeply as possible to keep the center lines of the rolls as close together as possible and, also, by making the spindles 93 and 94 as long as possible. This latter feature is aided by the fact that the rolls are quite short.

It will be understood that in the operation of the stand 75 and its associated drive that when the rolls 86 and 87 are used with the spindles 88 and 89 in doing substantial rolling work as shown in Fig. 10, the clutch 66 is actuated by the arm 72 so that the portions 69 and 71 are in engagement and the motor 31 drives directly through the shaft 67 into the stand. However, when the edging rolls 91 and 92 are used with long spindles 93 and 94, the clutch is not so engaged and the motor 32 drives directly through the shaft 73 into the shaft 67 of the stand.

A description of some aspects of the invention would appear to be in order. The concept of following each small group of horizontal stands with a vertical stand permits the mill to produce a wide range of shapes and sizes. The use of vertical stands having a dual drive i.e. high speed (low power) and low speed (high power) permits a wide range of operation. The high speed operation would be used when the vertical stand is used for edging,

as in the edge rolling of flat strip material such as 'skelp. The slow speed would be used when the vertical stand is used to actually reduce the section of the material being rolled, as when rod or bar is the product being produced. The question arises as to why one should use different speeds for these two types of operations when it is well known that the peripheral speed of the roll must always be the same as that of the material being rolled. The reason islthat, when the vertical stand is used for reduction of stock the rolls are close together and the angular misalignment of the drive spindles is relatively small, the rolls used are provided with a number of grooves to take care of several sizes and shapes of product and the spindles are permitted to be quite short, since there is little incentive to keep the drive spindles long. However, when the stand is used for edging, the rolls must be separated by a considerable distance; if long rolls and normal spindles were used, the angular misalignment of the spindles would be very great. Therefore, very short rolls and very long spindles are used, thus replacing the corresponding regularly-sized elements in the vertical mill. In order to assure the rolls be placed as close together as possible to keep'the angularity of the spindle to a minimum, the grooves are made very deep; this means that the effective diameter of the roll is very small and they must be driven at a much higher speed so that the surface speed of the bottom surfaces-of the grooves matches the speed of the edge of the strip. Since no electrical motor of practical cost is capable of speed adjustment over the range of speed between the rolling speed of the vertical mill and edging speed, it is proposed to use a double drive with ahigh speed motor and a low speed motor. (3f equal importance is the fact that the edging opera tion requires relatively little power so the high speed motor is also a small motor of little power. This saves the cost of electrical energy that would otherwise be required merely to rotate the large motor during edging. The use of the clutch 66, of course, assures that when the motor 32 is driving the stand, that the idle motor 31 does not have to be dragged along with it. The power required to merely drive the unenergized motor 31 would be quite considerable and would make the motor 32 much larger than is necessary. In the reverse situation, however, the motor 31 can carry the unenergized motor 32 without difliculty.

With regard to the particular arrangement of horizontal and vertical stands, the unusual effect that is obtained is that it is possible to roll precision bars or rod single strand (as in Figs. 3 and 4) without twisting, or to roll non-precision rod or bar double strand (as in Fig. 7) with twisting between strands. This particular sequence of vertical and horizontal stands makes it possible to produce a wide variety of products with a limited number of strands. Naturally, it would be possible to produce the same product in a mill containing alternate horizontal and vertical stands, as has been done in the past, but this could be done only by using a large number of stands and by dummying some of the stands. With such expensive equipment it is poor economics to have capital equipment standing around idle. It should be understood that the use of the arrangement of the present invention will permit a mill of a given capacity to be built with perhaps two less stands than if it were built along the idea of alternate horizontal and vertical stands. With rolling mill stands as expensive as they are, such a saving in the number of necessary stands is not to be disregarded. Furthermore, the alternate horizontal and vertical stand arrangement does not lend itself to the rolling of precision rod, strip or a double strand rod or bar since, when rolling this type of product, a number of vertical stands are totally useless (as in double strand rolling), or are not necessary in such large numbers (as in strip rolling). The first group of stands are the ones which make the difference. To be more specific, the following chart shows a comparison of the number of stands required ahead of the shear to-obtain the reduction of the same amount of metal as is shown in the drawings:

Total No. not Stands Used Present arrangement 9 3 Precislon rod {Alternate Vt rt. and ban.-. 6 Prose nt arrungemen 9 3 Bar rglternate vert. and bar 8 g resent arrangement Stup {lternate vert. and harp... 1g 2 r'tsent arrangemen Angles iAlternate vert and bar.. 13 6 Fig. 7, Double-Strand 'Present arrangement 9 2 N on-precision rod. {Alternate vert. and ban-.. 13 6 total reduction ahead of the shear, the present arrangement needs only nine stands, and at no time wastes more than three stands, while the alternate arrangement of the vertical and horizontal stand, which is old in the art, requires thirteen stands, and in some instances wastes six stands. That is why before the present invention it was not considered feasible to build rolling mills that would handle such a wide range of products of various types.

While certain novel features of the invention have been shown and described and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes in the forms and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention.

The invention having been thus described, what is claimed as new and desired to secure by Letters Patent 1. A vertical rolling mill, comprising a stand of two generally parallel rolls, a driven shaft for driving said 8 rolls, a high-power low-speed motor, a low-power highspeed motor, means connecting the low-power highspeed motor directly to the driven shaft, a drive means for the high-power low-speed motor comprising a transmission and a,clutch means adapted selectively to connect and disconnect the high-power low-speed motor to i the driven shaft.

2. A vertical rolling mill, comprising a stand of two generally parallel rolls, a driven shaft for driving said rolls, a high-power low-speed motor, a low-power highspeed motor, means connecting the low-power high-speed motor directly to the driven shaft, a drive means for the high-power low-speed motor comprising a transmission and a clutch means adapted selectively to connect and disconnect the high-power low-speed motor to the driven shaft, a hollow shaft rotatably mounted on the driven shaft, the said transmission including a gear keyed to the hollow shaft, the clutch having a first portion fastened to the driven shaft and a second portion which is fastened to the hollow' shaft.

References Cited in the file of this patent UNITED STATES PATENTS Kaerger Feb. 19,

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