US1737998A - Method of expanding metal - Google Patents

Description

Dec. 3, 1929. GERSMAN 1,737,998

METHOD OF EXPANDING METAL Filed Oct. 9, 1926 2 Sheets-Sheet 1.

gmwmtoz fiAFI/EY m ems/mm Dec. 3, 1929. H. M. GERSMAN METHOD OF EXPANDING METAL Patented Dec. 3, 1929 UNITED STATES PATENT ()FFEQ METHOD EXPANDING METAL Application filed October 9, 1926. Serial No. 140,522.

This invention relates to a method of expanding metal wherein the expansion is effected in connection with the elongation of the strands. The invention is generically applicable to the production of expanded metal articles of difierent kinds and for clifferent uses in structural operations, and is herein claimed in its generic aspect and also in one specific aspect, namely, the production of expanded metal beams or load bearing members.

The invention is practiced in connection with a heated blank and the method is completed before the blank has cooled to a degree suficient to interfere. with the working of the metal. Preferably the invention is practiced continuously with the delivery of the blank from a standard mill pass and the method is commenced with the blank at or near the degree of heat which it has at the delivery stage of the rolling operation.

The principal objects of the invention are to provide a method having the characteristics generally indicated and which is simpler and more rapid than methods heretofore pro posed and may be practiced with more compact and less expensive equipment; and to obtain a product of superior form and quality.

Generally stated, the invention consists in the correlation of steps of providing slits in the blank and of elongating the strands such that they are performed as parts of a single operation and that the extent of strand elongation and resultant expansion may be con- 5 trolled by elements involved in the provision of the slits, the resultant product being one in which the strands are uniformly homogeneous as to their miscrostructure and proportions. Instead of slitting the blank in the ordinary manner, that is to say by cutters which have a shearing action and which bodily displace and to some extent initially stretch the strands, thereby producing effects which must be overcome in any practically successful method and which add to the complexity of the method and of the equipment for its practice, I propose to treat the blank in such manner as to form the slits and simultaneously to displace laterally, in determined degree, some of the metal of the strands, without, however, stretching the strands. Such treatment of the blank is accompanied by the rolling of the strands simultaneously with the formation of the slits by which the strands are delimited, the metal displaced by the slit-forming operation being utilized for the elongation of the strands whereby the strands may have the same thickness which they had in the blank and the extent of elongation is proportionate to the amount of metal which is displaced by the slit-forming operation. One way of carrying out this treatment and which is herein shown is to score the blank by parts which have a wedge-like action and which form rows of slits whereby as the slits are formed a percentage of metal, which may be determined as desired, is deposited or caused to accumulate or lodge on the parts, i. e. the strands, between the rows of slits. During the elongation of the strands the width of the blank is successively and progressively increased between portions at each side which are not subject to the scoring and rolling actions, thereby simultaneously to compensate and continuously take up the elongation of the rolled portion at a rate corresponding to that of the elongation and wlth resultant expansion of the blank. of the blank may be effected in different ways and is herein shown as effected by spreading or fanning out the unrolled side portions. The method is thus one which may be completed in a single roll pass and in which no warping 0r buckling of the metal is produced or permitted. Moreover, there are no factors by which inequalities in form or physical characteristics are introduced or by which, as compared with cold expanding operations, any internal stresses are developed. It fol lows that the product is one in which the elongated strands and bonds are uniform in thickness, dimensions, physical qualities and microstructure, and may lie in planes coincident with the mean or general plane of the expanded article.

As applied to load bearing members the web is treated as above indicated and simultaneously rolled in the manner abcve generally described while the remain of The increase in the width line of the same length as in the blank and during the elongation of the strancs are simultaneously and progressively and at a rate proportionate to the elongation spread or fanned out so as to compensate the elongation as it occurs and ith resultant expansion of the blank into the load bearing member which, if desired, although this not strictly necessary, may be passed through finishing rolls.

The above and other characterizing features of the invention will be set forth in detail as the description proceeds and will appear from the accompanying drawings which illustrate apparatus by which. the method may be practiced, the steps in the evolution of the blank into the completed product, and a portion of an expanded beam produced by the method.

In said drawings:

Figure 1 is a plan view of the apparatus showing a'blank in tl e course of expansion.

Figure 2 is an end elevation of the guides which are used in the expansion of the blank, th being viewed at the ends at which on pension is completed.

F igure 3 is a cross-section of the rolls and of the part of the blank in the roll pass.

Figure i is a developed plan view of the bottom roll.

Figure 5 is a developed plan view of the top roll.

Figure 6 is a cross-section of the blank. F gure 7 is a cross-section of the blank elongation of the strands is in progress.

Figure 8 is a cross-section of the finished load bearing member.

Figure 9 is a fragmentary elevation of the finished load bearing member.

Figure 10 is a cross-section of rolls of al ternative form and of the part of the blank in the roll pass.

The method nreferabl practiced continuously and in connection with the rolling of the blank.

in such case the heat of the blar as it comes from the stand of the mill 2 which its development has beebrought to the stage desired utilized. and the method is completed with final determin tion of the and physical qualities of the expander arti :lc while the blank is yet suiliciently hot for its parts to be worked and relocated.

The method is applicable to different fornis of beams one ot expanded articles and is herein illustrated in. connection with the production of a beam in the form of a simple lattice truss wherein the struts have a single intermediate bonds representing points of intersection, the remaining bonds being the connections between the struts and the chords, that is to say, the panel points of the truss. p

The blank E (Figure 6) is shown as having a crosssection generally similar to that of a standard I-beam and is provided with parallel flanges 2 and a web 3 which have been suit-bly developed I an antecedent rolling operation.

' J ln this iorni the blank may be passed directly from the mill stand (not shown) to the apparatus oy which he present methoeis practiced.

Such apparatus, as shown in F igures 3, l and 5, consists essentially of a pair of cooperating upper and lower rol s 11 and 12 which not both to slit the blank and to elongate the resultant strands. The slitting may be accomplished by a scoring operation for the purpose of which the rolls 11 and 12 are formed with suitable scoring ribs 13 and 14 respectively. The beam may within practical limits have any desired number of rows of struts and bonds and the number and arrangement of the ribs 13 and i l may varied accordingly, the'arrangement shown being adapted for a simple lattice truss and providing for three rows of slits developed along parallel lines with the slits of the intermediate row staggered relatively to the slits of the two outer rows.

In the construction shown in Figs. 3, l and 5 the rios13 and l t are formed to penetrate the blank for its full thickness, the ribs 14 which provide the outer rows of slits being arranged in two rows and penetrating the web from below and the ribs 13 which provide the intermediate row of slits being a "ranged in a single row and penetrating the web from above. In addition to the scoring ribs the rolls are formed *ith working surfaces which operate on the upper-and lower faces of the strands delimited by the slits and which in their cooperating relation are parallel in the two rolls in the transverse direction. In the construction shown in Fig. 8 these working surfaces are laterally inclined or beveled. Tie upper roll 11 isformed with working surfaces 15 and 16 which are, respectively, at opposite sides of the row of ribs 13, tl ese surfaces extending transversely between the bases of the ribs 13 and lines which coincide peripherally with the apices of the ribs 1d. The lower roll 12 is formed with workin g surfaces 17 and 18 which lie between the rows of ribs 14". and extend transversely between the bases of said ribs and a line coinciding peripherally with the apices of the ribs 13. The working surfaces are mutually cooperative in pairs, one of which consists of the surfaces 15 and 17 and the other of surfaces 16 and 18, the working surfaces of each coopeating pair being inclined oppositely in the lateral direction from the working surfaces of the other pair. This arrangement of the working surfaces is of advantage where the scoring ribs penetrate the web for its full thickness in that it facilitates the operation of such ribs by providing opposite the apices thereof a thin bearing; .line from which the working surfaces rec-eds, thereby developing a tendency to break the web along longitudinal lines coinciding with thelinesof scoring and in this way minimizing the resistance to the action of the scoring ribs. A further advantage of the transversely inclined working surfaces is that the strands or struts as rolled are at such angles, transversely, that the axes about which they are bent during expansion is of minimum transverse depth so that mini mum resistance to the bending action is interposed with resultant lessening of the force required to produce suchbending action and of the liability of tea-ring at the bonds.

The ribs 13 and 14 are of triangular crosssection with sharply defined apices and penetrate the web with a wedging action, thus scoring the web and providing for the slits which are necessary for the expansion of the blank. In respect to the material of the Web which is confined between the ribs, that is to say the strands delimited by the slits, the effect of the ribs, due to their wedge form and action, is to displace laterally a. percentage of said material, the displaced material tending to accumulate on the upper and lower faces of the strands just back of the center of the roll pass and proportionately to increase the thickness of the strands. However, the depth of the roll pass as determined by the distances perpendicularly between the cooperating working faces, that is to say the faces 15 and 17 of one pair and the faces 16 and 18 of the other pair is less than the increased depth of the strands and is preferably no greater than the original thickness of the web from which it follows that said Working faces act on the excess metal displaced by the scoring ribs and proportionately elongate the strands without reducing their thickness, the displaced metal being thus used to provide for the elongation. The accumulation of displaced metal on the parts between the rows of slits commences as soon as the scoring ribs penetrate the blank and reaches its maximum at or substantially at the common center line of the rolls.

The percentage of metal displaced by the scoring ribs will depend on the angles of the sides of the ribs. By suitable selection of such angles the percentage of displaced metal can be varied and since the elongation is proportionate to the percentage of metal displaced the elongation can be correspondingly varied. Thus the angles of the sides of the ribs can be utilized to determine the elongation of the strands; for example, if a twenty percent elongation of the strands be desired the angles of the scoring ribs will be selected to displace twenty percent of the metal of the strands. If desired the elongation of the strands in the manner described may be modified by regulation of the depth of the roll pass. Thus instead of having the roll pass of the same depth as the thickness of the web it may be of slightly greater depth (but still less than the increased thickness of the strands caused by the accumulation of displaced metal) in which case the elongation of the strands will be proportionately reduced and the strands will be slightly thicker than the original thickness of the web or it may be of slightly less depth in which case the elongation of the strands will be proportionately increased and the strands will be of proportionately less thickness than the original thickness of the web.

The web on emergence from the roll pass will, owing to the elongation of the strands, travel at a greater rate than the blank as it approaches the roll pass, the increase of speed being proportionate to the percentage of elongation. For example, if the speed of the blank up to the reducing rolls be 100 feet per minute and a twenty-five percent elongation be provided for the speed of the Web on emergence from the roll pass will be 125 feetper minute. To compensate this elongation of the web relatively to the unelongated flanges which of course travel at a uniform rate the scoring and elongating rolls are employed in cooperation with means for initiatin g and controlling an increase in the width of the blank simultaneously and continuously with the elongation of the web, at a proportionate rate and in a proportionate degree. In the embodiment disclosed such means is constituted by shoes 19 and flange guides 20 (Figures 1 and 2). The shoes 19 are preferably provided in upper and lower pairs, one pair being associated with each scoring and elongating roll, and the the shoes of each pair having forwardly divergent guide faces 21 which bear against the inner faces of the flanges 2, with inclination of the faces 21 being determined in accordance with the requirements previously stated, that is to say to control the spreading or fanning out of the flanges at a rate proportionate to the elongation. The shoes 19 preferably engage the flanges substantially at or slightly ahead of the center lines of the rolls whereby they commence to act on the flanges substantially at the time of the application of pressure to the strands by the working faces of the rolls. Owing to the scoring operation the walls of the slits have their closest approach to one another only along lines substantially flush with a face of the web and, receding from such lines, are widely separated throughout the thickness of the web. Any tendency for the walls of the slits to freeze or weld due to the pressure of the working faces of the rolls is limited to the narrow lines from which the walls of the slits recede and is immediately counteracted and with a minimum of force by the initial action of the shoes 19 which thus insure that during expansion no stresses are imposed on the panel point bond providing portions such as might arise if it were necessary to separate any adjacent strands which had become partially welded.

The lateral deflection of the flanges initiated by the shoes 19 is practically continued by the strands themselves which, elongating at an angle to the direction of travel, (Figures 1 and 7 act somewhat in the manner of a toggle to move the flanges relatively outward, this spreading of the flanges being thus effected with minimum resistance and being controlled by the shoes 19. It will thus be noted that the spreading of the flanges is not resorted to for the purpose of elongating the struts and has no effect on the length of the struts but is in consequence of the elongation of the struts and is so controlled that the elongation of the web is continuously and proportionatel r compensated with reference to the unelongated flanges so that there is no tendency for the struts to buckle or to shear or partially shear from the adjacent chord portions. The spreading or fanning out of the flanges in connection with the elongation and lateral deflection of the struts results in the formation of the web into open Work to the degree required in the completed prodct. lVhen the lateral deflection of the strands has proceeded as far as may be desirable the action is arrested by the guides 20 which have parallel faces to engage the outer faces of the flanges 2 and direct said flanges along parallel lines. The guides 20 are effective at the time the elongation of the strands is completed and the product on emergence from said guides is the completed beam (Figures 1, 8 and 9), all parts of which travel at the same speed as the original blank. If desired the beam may pass from the guides 20 to finishin rolls (not shown) in order to eliminate any surface irregularities but this is not strictly necessary.

Figure 10 shows an alternative form of the web scoringand elongating rolls which, as in the embodiment described, are provided in a single pair and are employed in connection with the shoes 19 and guides 20. The modification consists in the form and arrangement of the scoring ribs and the working roll faces according to which the action proceeds with the strands in the original plane of the web instead of being oppositely inclined relatively to such plane as in the embodiment described.

The rolls 11f and 12 of Figure 10 are formed with peripherally coincident scoring ribs 22 arranged in three rows to produce three rows of slits as in the embodiment described, it being of course understood that as many rows as desired may within practical limits be provided. The ribs 22 have the characteristic wedge form and action above described but penetrate the web for only half its thickness, the penetration being simultaneous from both faces of the web. These rolls have working faces 23 which eX- tend between the bases of the ribs and are parallel, laterally, to the plane of the web.

As in the embodiment described the ribs displace a percentage of the metal which is confined between them and this percentage, which depends on the angles of the sides of the ribs, tends to accumulate on the web back of the roll pass and is utilized by the worklng faces 23 to effect the elongation of the strands, the action being similar to that described.

laving fully described my invention I claim:

1. The method of expanding metal which includes the steps of treating aheated blank to form slits along parallel rows and simultaneously so to displace a percentage of the metal of the blank as to cause the same to lodge on the surfaces of the parts lying between the rows of slits and immediately during the formation. of the slits rolling the blank to elongate the parts between the cleveloping slits and upon which the displaced metal has lodged.

2. Che method of expanding metal which is characterized by so slitting a heated blank to provide rows of slits as a part of an operation of rolling the metal between the rows of elite to displace a percentage of the metal cause the same to lodge upon the parts to be rolled.

3. The method of expanding metal which includes the steps effected in a single roll pass of so slitting a heated blank in rows as to displace metal and cause the lodgment of the same upon the parts between the rows of slits and rolling the parts upon which the displaced metal has lodged, thereby to elongate said parts. 7

a. The method of expanding metal which consists of the steps effected in a single roll pass of so slitting a heated blank in rows as to displace metal and cause the lodgment of the same upon the parts between the rows of slits and rolling the parts upon which the displaced metal has lodged, thereby to elongate said parts, and the further step of laterally deflecting the rolled parts immediately on their emergence from the roll pass to cause an increase in the width of the blank progressive with and proportionate to the elongation.

5. The method of expanding metal which consists of treating a heated blank to form slits along parallel rows and simultaneously so to displace a determined percentage of the metal of the blank as to cause the same to lodge on the surfaces of the parts lying between the rows of slits, rolling the blank to elongate the parts upon which the dis placed metal has lodged and laterally deflect ing the rolled parts continuously during their elongation and at a proportionate rate.

6. The method of expanding metal which includes the steps of so scoring a heated blank in rows as to form slits and producean accumulation of displaced metal on the parts of the blank between the rows of slits and so rolling the metal between the rows of slits immediately during the formation of the slits as to utilize the displaced metal for the elongation of the rolled parts.

7. The method of expanding metal by rolling and elongating parts between rows of slits in a heated blank wherein the blank is scored to provide the slits and the scoring operation is utilized to predetermine the percentage of elongation by causing the displacement of a determined percentage oi the metal of the blank on the portions thereof between the slits.

8. The method of expanding metal which includes the steps of scoring and rolling a heated blank in a single roll pass to form rows of slits and elongate the parts between the rows of slits.

9. The method of expanding metal which consists of the steps of scoring and rolling a heated blank in a single roll pass to form rows or" slits and elongate the parts between the rows of slits, and of laterally deflect ing the rolled parts immediately on their emergence from the roll pass to cause an increase in the width of the blank progressive with and proportionate to the elongation.

10. The method of expanding metal which consists of so scoring a heated blank in rows as to form slits and produce a determined accumulation of displaced metal on the parts of the blank between the rows of slits, so rolling the metal between the rows of slits as to utilize the displaced metal for the elongat-ion of the rolled parts, and laterally deflecting the rolled parts continuously during their elongation and at a proportionate rate.

11. The method of expanding metal which is characterized by effecting a wedge-like scoring action on a heated blank as apart of an operation of elongating by rolling and to provide rows of slits.

12. The method of expanding metal which is characterized by eflecting a wedge-like scoring action on a heated blank as a part of an operation of elongating by rolling whereby to provide rows of slits and to deposit on the parts between the slits a percentage of displaced metal by which the elongation eftected by the rolling is determined.

13. The method of making an expanded load bearing member from a heated flanged rolled blank which includes the steps eftected in a single roll pass of so slitting the web in rows as to displace metal and cause the lodgment of the same upon the parts between the rows of slits and rolling the parts upon which the displaced metal has lodged, thereby to elongate said parts, and the further step of laterally deflecting the rolled parts continuously during their elongation and at a proportionate rate, thereby to form the web into open work.

14. The method of making an expanded load bearing member from a heated flanged rolled blank which consists of the steps ef- :tected in a single roll pass of so slitting the web inrows as to displace metal and cause the lodgment of the same upon the parts between the rows of slits and rolling the parts upon which the displaced metal has lodged, thereby to elongate said parts, and the further steps of laterally deflecting the rolled parts continuously during their elongation and at a proportionate rate, thereby to form the web into open work, and of arresting the lateral deflection on the termination of the elongation, thereby to deliver from said roll pass a complete expanded beam.

15. The method of making an expanded load bearing member from a heated flanged rolled blank which includes the steps of so scoring the web of the blank in rows as to form slits and produce an accumulation of displaced metal on the parts of the web between the rows of slits and so rolling the metal between the rows of slits immediately during the formation of the slits as to utilize the displaced metal for the elongation of the rolled parts. I

16. The method of making an expanded load bearing member from a heated flanged rolled blank which includes the steps of scoring and rolling the web of the blank in a single roll pass to form rows of slit-s and elongate the parts between the rows of slit-s, and of laterally deflecting the rolled parts immediately on their emergence from the roll pass to cause an increase in the width of the blank progressive with and proportionate to the elongation, thereby to form the blank into open work.

17. The method or" making an expanded load bearing member from a heated flanged rolled blank which consists of the steps of scoring and rolling the web of the blank in a single roll pass to form rows of slits andelongate the parts between the slits, of laterally deflecting the rolled parts immediately on their emergence from the roll pass to cause an increase in the width of the blank progressive with and proportionate to the elongation, thereby to form the blank into open work, and of arresting the lateral deflection on the termination of the elongation, thereby to deliver from said roll pass a complete expanded beam.

In testimony whereof I hereby aflix my signature.

HARVEY M. GERSMAN.

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