US2084469A - Apparatus for rolling flat sheetlike material - Google Patents

Description

R. J. WEAN June 22, 1937.

APPARATUS FOR ROLLING FLAT SHEET LIKE MATERIAL Filed Feb. 20, 1934 Patented June 22, 1937 PAT s."

FFICE APBARATUS FOR ROLLING FLAT SHEET- LIKE MATERIAL Raymond J. Wean, Warren, Ohio, assignor to The Wean Engineering Company, Inc., War.- ren, Ohio, a corporation of Ohio Application February 20, 1934, Serial No. 712,159

4 Claims.

This invention relates to a method and apparatus for the rolling of fiat sheet-like material and permits of rolling such material accurately and with a high quality of surfaceat relatively V low cost and in an installation whose capital cost as compared with mills of the continuous type is very low.

The rolling of Wide strip has developed rapidly in recent years and the general practice has been to roll a slab down. to the desired hot rolled gauge by a single passage through a continuous mill. In some cases the slab is rolled from an ingot and is then reheated, and in other cases it is formed and then supplied to the continuous mill and rolled down to gauge in the original heat. Continuous mills are highly expensive and unless operated most of the time are very costly because the fixed charges are so high. The high cost of mills of this character makes it impossible for many manufacturers to install the same. I

provide a mill consisting of few stands and arranged for the production of hot rolled'strip at a relatively low capital cost and at an operating cost which is competitive with the continuous mill. '25"My improved mill is particularly desirable because of the recent trend in the industry toward the production of tin plate and other thin metal sheets by cold rolling. My installation provides a ready means whereby a manufacturer may provide himself with hot strip capacity to supply a relatively simple and inexpensive cold strip mill. It is to be understood, however, that the above statement is by way of illustration only, and that the product of the mill may be used wherehot strip produced by other methods is used.

Briefly, I provide a universal mill in which a heated slab is rolled back and forth to form a plate, which plate is supplied to a second mill wherein it is again rolled back and forth into a strip. During the latter rolling the ratio of sur-- face area to volume of the piece being worked increases so greatly that provision must be made for keeping the strip up to temperature. I therefore provide furnaces on each side of the stand into which the piece is fed after it issues from the mill on one pass and from which it is fed to passes is as fol1ows:I have observed that where the material is coiled between passes it tends to break up the adherent scale into small pieces which, while they do not fall on the strip, are adherent thereto over only apart of the surface. In other words, the small particles of scale are tilted with respect to the metal as it goes onto the coiler, thus allowing access of air to the metal at the exposed portions and causing the formation of additional secondary scale in such spaces and beneath the scale first above described. As a consequence, the formed scale in its entirety is not uniform as to thickness but rather is in the nature of a. series of fine, wedge-like bodies.

f The formation of the scale in this fashion makes Figures 1 to 4 inclusive are views showing a slab heating furnace and a universal mill for reducing slabs to plate form, the several views showing successive reductions;

Figures 5 and 6 are similar diagrammatic views but showing the universal stand and also showing the finishing stand, its associated furnaces, and a. coiler for handling the finished product;

Figures 7 to 9 inclusive are views of the finishing stand and associated parts showing successive stages in the rolling; and

Figure 10 is a transverse section to enlarged scale showing the interior construction of one of the heat conserving chambers.

Figure 1 illustrates a universal mill having horizontal reducing rolls 2 and edging rolls 3. The mill is supplied with slabs S from a heating fur nace 4. In the first pass the slab is thinned and elongated as illustrated at Sl. In Figure -1'the direction of rolling in the first pass is indicated by an arrow: The mill is then reversed and the slab SI is rolled to the form of a thinner slab S2. The operation is repeated by reversing the mill so that the slab is successively rolled to thinner and thinner section as indicated at 8-3, 8-4 and SS in Figures 3 to 5 inclusive.

After being reduced to plate form as shown at 8-5, the material passes over a roll table 5 to the finishing mill 6. This mill has working rolls I of relatively small diameter supported by large diameter backing rolls 8 which are preferably mounted in roller bearings. If desired, a 3high mill having a small middle roll and large diameter top and bottom rolls may be employed. The plate is rolled back and forth in the mill 6 until the desired thickness is reached and is then delivered from the mill. As an example, it may be desired to start out with slabs S which are 4 to 6 inches thick; to roll these into plates whose,

thickness may be from inch to 1 inches, and then in the finishing mill to roll such plates to final gauge, which may be 16 gauge or even thinner.

As above stated, it is necessary to keep the material hot in order to successfully roll it and this is accomplished by providing furnaces 9 and I0, one on either side of the mill 6. As shown in Figure 10, the furnaces are provided with a set of conveying rolls II below the furnace hearth and an upper set of conveying rolls I2 within the furnace. Tiltable sections I3 and I 4 are provided for the upper rolls I2 at each end of the furnace. The upper series of rolls is used to support a piece which is being heated prior to being rolled, and the lower rolls I I are used for those pieces which are in process of being rolled and are hot enough to be rolled without immediate reheating. In traveling from the roughing mill 2 to the finishing mill 6, for example, it may be desirable to feed the plate onto the upper rolls I2, as indicated at P in Figure 5, where it can be held and maintained at high temperature or further heated, depending on the temperature of the furnace, after which it can be fed out of the furnace and downwardly, as indicated at P-I, for the first ass through the finishing stand 6. The resulting plate is indicated at P-2.

Figures 6 to 9 inclusive show successive rollings of the plate Pso as to form progressively longer nieces P3, P-l, P-5 and P6. The piece P-5 is the final product and, as will be noted from Figure 9, it leaves the niill and passes through the furnace I0 via its upper set of conveying rolls I2 or below the furnace on rolls II so as to be out of the way of the succeeding piece.

The conveyor I I is enclosed by a muilie, as shown,

' to conserve heat. The finished piece is fed to a coiler I5 where in it is rolled into coil form as indicated at C in Figure 9.

While, as will be noted, the materiaimay be diverted slightly from a true plane during .the rolling in the finishing mill, it is at no time coiled prior to the last pass. The advantages of this from the standpoint of scale structure have been pointed out above.

The material will be at a substantial temperature on leaving the mill 2. The additional heat necessary to finish the piece in the mill 6 is supplied by the furnaces 9 and I0. This heat may be added-while the material progresses through the furnaces or, alternatively, the material may be permitted to dwell in one or both furnaces to absorb heat as desired for further rolling. By using the lower conveyor rolls II, however, the material may be given several passes through the mill without entering the furnaces, if sufiiciently heated. Should the desired gauge of the finished material require heating facilities in ex- .cess of those shown, a second set of conveyor rolls could be installed in the furnaces 9 and I0 above those shown at I2, with suitable tilting guides similar to-those indicated at I3 and I4, constituting a double deck furnace conveyor.

' While I have illustrated and described a present preferred embodiment of my invention, it will be understood that the same is not limited thereto but may be otherwise embodied and practiced within the scope of the following'claims. 'Iclaim:

1. The combinationwith a reversing hot strip mill, of a furnace on one side of the mill, means for delivering strip to one end of said furnace for heating prior to entry into the mill, means for conveying the heated stripfrom the other end of the furnace to the mill, and means on the same side of the mill as the furnace, external thereto, and substantially co-extensive therewith, for receivihg strip issuing from the mill and supporting it in substantially flat form.

2. In a rolling mill, the combination with a stand of reducing rolls, of a stationary furnace on one side thereof having an elongated heating chamber disposed with its longitudinal axis at right angles to the plane containing the axes of the rolls, means for delivering a strip blank to the chamber, means for discharging it to said stand when heated, means in the chamber for receiving it and supporting it in the fiat, and means outside said chamber but substantially co-extensive and vertically alined therewith, for

receiving strip from the mill and supporting it i in the flat.

3. The combination with a reversing hot strip mill, of a stationary elongated furnace on one side of the mill with its longitudinal axis extend-- ing substantially perpendicular to the plane containing the axes of the mill rolls and adapted to heat the strip between successive passes therethrough, means in the furnace for receiving the strip and supporting it in the flat, a conveyor substantially in the vertical plane of the furnace but external thereto adapted to receive the strip in the fiat when it is not to be reheated preparatory to further rolling, and means at the end of the furnace remote from the mill for diverting material approaching the mill to either said furnace or said conveyor.

4. The combination with a reversing hot strip mill, of a stationary elongated furnace on one side of the mill with its longitudinal axis extending substantially perpendicular to the plane con- RAYMON J. WEAN.

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