US2035344A - Metal container and method of making the same - Google Patents

Description

'- March 24; 1936. w. R. ROBINSON METAL CONTAINER AND METHOD OF MAKING THE SAME Filed Jan. 4, 1 954 Patented Mar. 24, 1936 UNITED STATES METAL CONTAINER AND METHOD OF MAKING THE SAME William R. Robinson, Niles, Ohio Application January 4, 1934, Serial No. 705,172

8 Claims.

This invention relates to improvements in metal containers and method of making the same. It has to do particularly with ice cans which are sheet metal' containers employed in connection with ice making apparatus for holding the water to be frozen. They are made of fairly heavy gauge sheet metal, generally galvanized steel, and are of rectangular form, being open at the top and closed at the bottom.

It is important that the cans be rust resisting to as great a degree as possible. Rust in suspension in the water retards freezing time, discolors the ice and gives it an unpleasant taste, and in addition causes the cans to deteriorate.

In accordance with the present invention I use a continuous welded joint on account of the manufacturing advantages which such a joint possesses in the way of economy and speed of production. While an overlapped joint may be satisfactory and even desirable in some cases, I prefer as a rule to use a butt joint. The welding heat tends to damage the galvanizing adjacent the seam, and the fin produced by the weld is of course devoid of any galvanizing. Hence, in

order to protect this portionof the can against rust it is necessary to apply to it some metallic coating which is resistant to rust. The dipping of the can into molten metal for this purpose, after the weld is made, tends to distort the metal of the can and produce buckling, which, in some cases, is of such extent as to interfere more or less with the removal of the ice cakes, and furthermore detracts from the appearance of the .l can and makes it unsalable on that account.

The precise reason for buckling is diflicult to ascertain, but it occurs after the corner of the can which includes the seam has been immersed in the molten metal, the temperature of which may be several hundred degrees Fahrenheit and varies with the character of the metal used. The sudden raising of the temperature of this portion of the can and its subsequent cooling appear to subject the metal to internal stresses, and those stresses probably tend to produce a shortening or shrinkage of the two adjacent metal sheets at the butt seam and on both sides of that seam.

I have discovered that a working of the metal at the welded, joint, after the weld is made and before the j int is dipped in molten solder or 50 other molten metal or alloy, overcomes the tendency to buckle heretofore mentioned. It is my belief that the working of the metal at the joint tends to increase the length of the joint and therefore provides a condition prior to the shrinkage above referred to,'which compensates joint ice cans during their construction which shall substantially eliminate buckling in the side walls of the can.

Other objects and features of novelty will appear as I proceed with the description of those embodiments of the invention which, for the pur-, 15

poses of the present application, I have illustrated in the accompaning drawing, in which.

Fig. 1 is a perspective view of an ice can embodying the invention and built in accordance with my improved method. 20

Fig. 2 is a fragmentary elevation showing one of the Welded joints in the can.

Fig. 3 is a fragmentary cross sectional view on a larger scale, the view being taken substantially on the line 3-3 of Fig. 2. 25

Fig. 4 is a similar view with the welding fin removed.

Figs. 5 and 6 are side end views, respectively, of a toothed roller which may be employed for working the metal of the weld fin. 30

Figs. 7 and 8 are side and end views, respectively, of a plain'roller which may be used for the same purpose, and

Figs. 9 and 10 are side and end views, respectively, of a roller with an annular groove therein 35 adapted to clear the weld fin and enable the application of pressure by the roller upon the can walls on either side of the fin.

The side and end walls of the can are formed preferably of two sheets I0 and II of galvanized 0 metal, the sheets being identical in size and joined along their adjacent edges by seams l2. These seamsare butt seams and the joint is made by welding. Any of the well known methodsof welding butt joints of this character may be employed, although it may be stated that for practical reasons I prefer electric welding to gas welding.

In the welding operation there is thrown up along the outer side of the can at each seam a fin l3 This fin does not present a ridge of absolutely uniform height and cross section, but its surface is somewhat wavy or uneven, For a reason which will presently appear, each of the two seams I 2 islocated quite close to the adjacent corner of the can. In practice I prefer to make this distance between the seam and the corner three-fourths to seven-eighths of an inch. When the two seams I2 have been welded, I place the open-ended, unfinished can upon an elongated anvil or bar of suitable form with one of the fins I3 uppermost, and work the metal at the seam against such anvil in such manner as to lengthen the seam to a slight extent. This working is referred to hereinafter as malleating, by which term I intend to include any operation, such as rolling, which tends to alongate the seam, in other words any working of the metal which brings into play, or depends for its functioning upon, the malleability of the metal. In a can of forty-five inch depth, for example, the elongation at the seam may be of the order of threesixty-fourths of an inch. This elongation may be effected in various ways, but I prefer to employ a roller I4, shown in Figs. 5 and 6, having teeth I5 therein, which roller is caused to traverse the fin I3 lengthwise under considerable pressure exerted against the anvil, whereby a series of transverse indentations I6 are impressed into the fin, thereby elongating the same. Furthermore,-since the fin is an integral part of the can at the seam, the elongation of the fin also lengthens correspondingly the wall of the can at the seam and on either side thereof. A special machine of suitable design may be employed for doing this work quickly and effectively. As soon as the roller has been caused to traverse one of the fins I3, the open-ended, unfinished can may be turned upon the anvil or bar support to bring the other fin I3 uppermost, when the operation is repeated.

In Figs. 7 and 8 I have illustrated a plain roller II which may be employed instead of the toothed roller I4, sufficient pressure being exerted by the roller upon the surface of the fin I3 and against the supporting anvil to work the metal in the fin and elongate it together with the metal of the can adjacent thereto.

The action of the roller I4 is somewhat more effective and certain than that of the smooth roller I1, and is to be preferred upon that account in cases where the indentations I6 are not considered objectionable.

The roller I8 illustrated in Figs. 9 and 10 may also be employed if desired for elongating the metal of the can at the seam I2. In this roller I provide an annular groove I9 of sufficient width and depth to receive the fin I3 with clearance, so that the smooth surface of the roller on either side of the groove may bear upon the wall of the can adjacent the fin, and by the application of rolling pressure work the metal in such a way as to elongate the can wall adjacent the seam on either side thereof, such elongation being necessarily imparted also to the fin inasmuch as that is an integral part of the wall. A roller of this type of course does not deface the can in any way.

The application of the metal coating to the seams may be effected by means of any apparatus which will bring about direct contact of molten metal with at least the outside wall of the can along and adjacent to the seams. I prefer to employ a trough as a container for the molten metal. I then support the can horizontally with one of the seam corners down, and dip it into the trough far enough to immerse both sides of the seam. The location of the seam close to the corner, as previously described, is an advantage, because the can may then be immersed a short distance only below the level of the molten liquid. The can is then raised above the level of the liquid and inclined endwise to cause all excess metal to flow off. It is then turned on its axis 5 and the other steam is coated by the same procedure.

In cases where a can of particularly fine finish and appearance is desired, I proceed in the following manner. The welds are made in the usual way, producing the fins I3 as previously stated, after which the fins are rolled with the toothed roller I4, producing the result illustrated in Figs. 2 and 3, with the required elongation of the seam. Now, instead of proceeding at once to apply molten metal to the joints for protection against rust, I remove the indented fins I3 by some suitable machining or grinding operation, leaving the joint plain and flush as shown in Fig. 4, after which the molten metal is caused to flow over the joints, inside and out. If preferred, a portion only of the metal of the fin may be removed, sufficient to efface the marks of the toothed roller and to smooth up the wavy irregular appearance of the fin. I have discovered that the seams apparently retain the elongated set given them by the rolling operation in spite of the removal of all or part of the fin, so that immersion of the joint in molten metal merely takes out this preliminary distortion and leaves the metal of the can at the seams free of strain and consequently free of any tendency to buckle. This method or procedure produces a butt joint which is of perfect appearance, devoid of any disfiguring marks, well protected against rust, and entirely free of any tendency to buckle the metal of the can.

When the open-ended, unfinished can has been produced by my method in accordance with one of the foregoing procedures, a reenforcing rim 20 is welded or riveted to the upper edge of the can, and a bottom with an upturned flange ZI' is attached to the side walls by welding, or riveting, or otherwise. The lower end of the can is then dipped in molten metal so as to protect the metal of the can at that seam against rust and to seal the joint there, in case anyfurther sealing is necessary.

While I prefer to apply molten solder to the seams and end joints of the can as the rust resisting coating, other molten metals or alloys may be substituted, molten zinc or molten tin being satisfactory for the purpose in most instances.

Having thus described my invention, I claim:

1. The method of manufacturing a sheet metal can having a welded seam in a side wall thereof, which comprises welding the seam, elongating the seam to a slight extent by a rolling operation on the fin or bead formed by welding, and thereafter applying to the can upon and along the seam molten metal resistant to oxidation.

2. The method of manufacturing a sheet metal can having a continuous welded butt seam in a side wall thereof, which comprises welding the seam, malleating the fin or bead produced by the weld, and applying to the can along the seam molten metal resistant to oxidation.

3. The method of manufacturing a sheet metal can having a continuous welded butt seam in a side wall thereof, which comprises welding the seam, elongating the fin produced by the weld, and applying to the can along the seam molten metal resistant to oxidation.

4. The method of manufacturing a sheet metal can having a continuous welded butt seam in a side wall thereof, which comprises welding the seam, malleating the fin produced by the weld, removing at least a. portion of the fin, and applying to the can upon and along the seam molten metal resistant to oxidation.

5. The method of manufacturing a sheet metal can having a continuous welded butt seam in a side wall thereof, which comprises welding the seam, elongating the weld fin by indenting the same at intervals, removing metal from the fin to the extent at least of eliminating the indentations therein, and applying to the can along the seam molten metal resistant to oxidation.

6. The method of manufacturing a sheet metal can having a continuous welded butt seam in a wall thereof, which comprises welding the seam,

elongating the weld by a rolling operation performed lengthwise of the 'weld, and applying molten solder to the can upon and along said seam.

7. In a metal can, bottom and side walls, a side wall of the can having a welded joint extending lengthwise of the can, the fin produced by the weld having transverse indentations therein, and the fin and the can adjacent thereto having a coating of metal resistant to oxidation.

8. In a metal can, bottom and side walls, a side wall of the can having a welded joint therein extending longitudinally of the can close to one corner thereof, the fin produced by the weld having transverse indentations therein, and the fin and the can adjacent thereto having a coating of metal resistant to oxidation.

WILLIAM R. ROBINSON.

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