US796452A - Method of manufacturing planished sheet metal. - Google Patents

Description

No. 796,452. PATENTED AUG. 8,1905.

A. RIDD. v METHOD OF MANUFACTURING PLANISHED SHEET METAL.

APPLICATION FILED APR.14, 1905.

Witnesses lniveintor 4&6" M- Attorneys mn'new, a. GRAHAM cu, PHOKO-LITHOGRAPNERS. WASHINGTON. a. c.

UNITED STATES AT NT OFFICE.

AMBROSE RIDD, OF NEWPORT, KENTUCKY.

Specification of Letters Patent.

Patented Aug. 8, 1905.

Application filed April 14:, 1905- $8Tial No. 255,624:-

To all whom it may concern.-

Be it known that I, AMBROSE RIDD, a citizen of the United States, residing at New port, in the county of Campbell and State of Kentucky, have invented a new and useful Method of Manufacturing Planished Sheet Metal, of which the following is a specification.

This invention relates to the manufacture of planished-metal sheets, and'has for its principal object to produce an article of a quality and appearance equal to that class of sheet metal known as Russian sheet-iron.

In the accompanying drawings, Figure 1 is a diagram of an apparatus which may be employed in carrying out the improved method. Fig. 2 isa detail view illustrating, on a larger scale, the rolling operation by which the planishing of the sheets is effected. Fig. 3 is a side elevation showing the gearing connections of the planishing-rolls.

Similar characters of reference are employed to indicate corresponding parts throughout the several figures of the drawings.

Many attempts have been made in this country to manufacture the flexible planished sheet metal known as Russian sheet-iron; but so far as I am aware this has never been accomplished successfully, at least on a commercial scale, and while planished sheets have been produced the surface of the metal has not been sufiiciently condensed to form a skin or enamel of such nature as to resist exposure for any considerable length of time, and none of the sheets can be seamed without breaking the skin or enamel on one or both sides.

In carrying out the present invention the following steps are pursued in the order named:

First. Sheets of steel formed by the ordinary processes of tight or loose rolling are delivered from the rolls ainto an annealing-oven 1 and gradually heated to a dark cherry-red.

Second. The sheets heated to dark cherryred are passed singly through a pair of rolls 2, that are heated almost to a dark cherry-red, both rolls being positively driven and having the same surface speed. These rolls serve to reduce the sheets to the extent of about one gage.

Third. The sheets are delivered from the rolls 2 into an annealing-oven 3, where the sheets are retained for a period of from twelve to twenty-four hours at a temperature of about 1,200 to 1,300 Fahrenheit until the required softness is obtained, after which the temperature in said oven is gradually lowered until the sheets have reached a temperature of 400 to 600 Fahrenheit.

Fourth. From the annealing-oven 3 the sheets are delivered in packs, the number in each pack varying as desired. In some instances three sheets may form a pack, while in others eight sheets, more or less, may be employed. These packs of sheets, heated to the temperature mentioned, are passed through a pair of rolls 4, that are heated to a temperature higher than that of the sheets, preferably to a dark cherry-red. These rolls are preferably of the same diameter and have gears at both ends, the gears being differentialthat is to say, the gears of the lower .roll are of smaller diameter than those of the upper roll, so that the surface speed of the lower roll will be greater than that of the upper roll. In practice this may be about onetenth. From the rolls 4: the packs of sheets are delivered to an annealing-oven 5. The sheets are then subjected to a gradually-increasing temperature until they have reached about 1,000 Fahrenheit and retained at this temperature for about twelve hours. The oven is then allowed to cool gradually, and the sheets are then in condition for use.

It is found during the course of manufacture that where the sheet and the rolls are heated to approximately the same temperature that the oxid formed on the surface of the sheet will be condensed and the gage of the sheet reduced without danger of chilling or checking, and the surface by this step will be placed in proper condition for the subsequent operation. The oXid will to some extent be condensed by the passage of the single sheets through the rolls 2, and in the final rolling process, where the sheets are passed between the differential rolls in packs under comparatively light pressure, the upper and lower sheets will be fed positively forward by engagement with the heated rolls, thelower condensing of the surface and the formation of a skin or enamel of such nature as to reslst exposure to the weather for a very long period of time, while at the same ,time the metal is freely flexible and may be seamed wkithout cracking or injuring the enamel or s 1n.

While the outer sheets of the rolled pack are employed for various purposes, it is found in practice that the surface in contact with the rolls will not be finished to the same extent as the skin or enamel characteristic of the intervening sheets.

In some cases, especially when it may be desired to reduce the thickness of the sheets, an additional rolling of the single sheets may take place before they are assembled in packs for the final rolling process.

In cases where a cheaper grade of imitation Russian sheet-iron is to be made the sheets are taken as they come from the final process of a tight or loose mill, usually in packs of six sheets each, without annealing or pickling and are treated as follows:

First. The packs of sheets are placed in an annealing-oven and the temperature is gradually raised to about 900 Fahrenheit.

Second. The sheets are now rolled in packs by the differential rolls under comparatively light pressure, passing directly from the oven to the rolls and thence directly into a second oven at the same temperature. The packs are again passed through the rolls in the reverse direction from the second to the first annealing-oven, and the process is repeated as often as necessary until the desired glaze has been attained, the sheets being maintained at a constant temperature of about 900 Fahrenheit and the rolls at a temperature of about 700 Fahrenheit. In this manner the rolling of the sheets on each other will form the desired glaze and a fairly good imitation of Russian sheet-iron will be produced.

Where the sheets are of heavy gage, successive coatings of oxid may be formed by the heating operations, and by the rolling processes between heating operations the coatings of oxid will effect the planishing of the sheets, as hereinbefore described. Care must be taken, however, to prevent formation of oxid to too great a depth, as this will Weaken and impair the elasticity of the sheet.

In the preparation of the rolls for this class of work the rolls after being turned in the lathe are placed in position between the cheek-plates. The engine is then started, and the screws are set so that the roll-surfaces bear equally on each other. Heat is then applied to the rolls until they have nearly reached about cherry-red; but in the meantime the rolls are kept turning steadily, and during expansion the roll-surfaces are pressed tightly together to such an extent that the surfaces are condensed, surfaces prepared in this way being found more effective in the production of the glazed sheets described than rolls which are finished and polished in the ordinary manner.

Having thus described the invention, what is claimed is 1. That method of planishing metal sheets which consists in effecting sliding frictional .engagement of oxid-coated sheets while the facturing planished-metal sheets, said method consisting in rolling the sheets, while both the sheets and rolls are at a high temperature; gradually reducing the temperature of the sheets; assembling the sheets in packs, and finally, passing each pack through rollsdriven at unequal speeds and at a higher temperature than that of the sheets.

5. The herein-described method of manufacturing planished-metal sheets, said method consisting in effecting a preliminary rolling of the single sheets by rolls of the same speed;

passing the rolled sheets to an annealing-oven;-

passing the single sheets from the oven through rolls heated to about a dark cherryred; assembling the singly-rolled sheets in packs, and maintaining the same at approximately the temperature of such second rolling; passing the pack of sheets through rolls under light pressure rotating at unequal speeds and heated to approximately a dark cherry-red, and finally, allowing the sheets to cool over a comparatively long period of time.

6. The herein-described method of manufacturing planished-metal sheets, said method consisting in gradually heating the sheets in an annealing-oven to about a dark cherry-red; passing the sheets singly through a pair of rolls that are heated almost to a dark cherry' red; passing the rolled sheets to an annealing-oven and retaining the same at a temperature of about 1,200 to 1,300 Fahrenheit, until the required softness is obtained; gradually reducing the temperature of the oven until the sheets havereached a temperature of from 400 to 600 Fahrenheit; delivering the sheets from the oven in packs; passing the packs of sheets through a pair of rolls that are heated almost to a dark cherry-red, said rolls rotating at unequal speeds; placing the packs of sheets in an annealing-oven and sub- 796,452 r at jecting the same to gradually-increasing tem- I my own I have hereto afiixed my signature in peraturg until thiey have reached albout 1,000 the presence of two witnesses. Fahren eit, an maintaining t is temperature for twelve hours more or less, and AMBROSE RIDD' finally allowing the sheets to gradually cool Witnesses: in the oven until in condition for use. 7 H. L. HAWKINS,

In testimony that I claim the foregoing as J. C. DE Moss.

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