MX2014009808A

MX2014009808A - Dies for shaping containers and methods for making same.

Info

Publication number: MX2014009808A
Application number: MX2014009808A
Authority: MX
Inventors: Robert E Dick; Anthony J Fedusa; Gary L Myers
Original assignee: Alcoa Inc
Priority date: 2012-02-17
Filing date: 2013-02-15
Publication date: 2014-09-25
Also published as: CL2014002124A1; EA201491538A1; EP2814628A1; BR112014020239A2; CA2864123A1; WO2013123396A1; AR090082A1; JP2015508711A; AU2013202226A1; US20130291612A1; ZA201405982B; CN103317014A; CN203470642U; GT201400176A; BR112014020239A8; KR20140125869A

Abstract

A method of manufacturing a die (10) for shaping metal containers comprises providing an expansion die (10) for manufacturing metal containers and peening at least a portion of the work surface (12) of the expansion die. Another method of manufacturing a die (30) for shaping metal containers comprises providing a die (30) for narrowing a diameter of metal containers and peening at least a portion of the work surface (32) of the die.

Description

MATRIXES OF FORMING CONTAINERS AND METHODS OF ELABORATION OF THEMSELVES Background of the Invention In the container industry, metal beverage containers that are formed in a substantially identical manner are produced in a massive and relatively inexpensive manner. For the purpose of expanding the diameter of a container to create a shaped container or to lengthen the diameter of the entire container, several operations using different expansion matrices are often required to expand each metal container in a desired amount. Also, the matrices have been used to reduce and shape the containers. Often, several operations are required which use different recessing matrices to decrease each metal container by a desired amount.

Summary of the Invention An expansion matrix for the manufacture of metal containers comprises a work surface that is configured to expand the diameter of a metal container having a closed bottom. The work surface comprises a portion that expands progressively and a projection. The outer diameter of the projection is the maximum diameter of the matrix.

In some embodiments, the portion of the working surface of the expansion matrix has a surface finish that has a maximum ratio of the closed vacuum area in the range of approximately one of 1-30%, 4-26%, 10-26. %, 10-20%, 10-15% and 12-15%. In some embodiments, at least the portion of the projection of the expansion matrix has a surface finish that has a maximum ratio of the closed vacuum area in the range of approximately one of 1-30%, 4-26%, 10-26%. , 10-20%, 10-15% and 12-15%. In some embodiments, at least the section of the portion that progressively expands has a surface finish that has a maximum ratio of the closed vacuum area in the range of approximately one of 1-30%, 4-26%, 10- 26%, 10-20%, 10-15% and 12-15%. The maximum ratio of the closed vacuum area is the closed area of vacuum / total measured area (100 times percentage).

In some embodiments, the portion of the working surface of the expansion matrix, which includes a portion of the progressively expanding portion and / or the projection, has a closed normalized vacuum volume in the range of approximately one of 1-2000 mm3 / m2, 9-1674 mm3 / m2, 33-388 mm3 / m2, 100-300 mm3 / m2, 100-250 mm3 / m2, 125-250 mm3 / m2, 150-250 mm3 / m2 and 155 -231 mm3 / m2. The closed normalized vacuum volume is the closed vacuum area that determines the depth of the area and quantifies the amount of lubricant that is capable of being trapped in the valleys of the surface.

The progressively expanding portion has dimensions and a geometry that when inserted into the open end of a container works on the side wall of the container to radially expand the diameter of the container in a progressive manner as the container travels along the work surface.

With respect to expansion matrices, a projection is the portion of the work surface of an expansion matrix having the largest outside diameter that contacts a section of a container while the matrix is expanding the container. It is possible that the matrix has multiple sections, each section has a projection, each projection has a different outside diameter. The projection having the smaller outer diameter travels farther towards the container than the projection having the larger outer diameter. The example of the matrix that has multiple projections can be seen in Figure 1.

In some embodiments, an initial portion of the working surface of the expansion matrix has the geometry for the formation of the transition in a container from an original diameter portion to an extended diameter portion. In some modalities, the transition is stepped or gradual.

In some embodiments, the expansion matrix has a biased portion, wherein the projection lies between the progressively expanding portion and the biased portion. The projection portion has dimensions and a geometry for adjusting the final diameter of the container being formed by this expansion matrix. In one embodiment, the length of the projection of the expansion matrix could be 0.3048 centimeters (0.12 inches) or more. In other embodiments, the length of the projection of the expansion matrix could be 0.0254, 0.504, 0.1016, 0.127, 0.2032, 0.254 centimeters (0.010, 0.020, 0.04, 0.05, 0.08 or 0.10 inches) or more or less. In one embodiment, the protrusion length of the expansion matrix is in the range between the linear contact of a continuous radius at 0.0254 centimeters (0.01 inches). In some embodiments of the expansion matrix, the biased portion follows the outgoing portion. In some embodiments of the expansion matrix, the transition from the projecting portion to the biased portion is combined.

In some embodiments, at least the portion of the biased portion has the average surface roughness (Ra) of approximately 0.00020320 to 0.00081280 millimeters (8 to 32 μ inches). In some modalities, the The portion that expands progressively has an average surface roughness (Ra) of approximately 0.000050800 to 0.00015240 millimeters (2 to 6 μ inches). In some embodiments, at least the portion of the projection of the expansion matrix has the average surface roughness (Ra) of approximately 0.00020320 to 0.00081280 millimeters (8 to 32 μin). In some embodiments, at least the portion of the working surface of the expansion matrix, which includes at least the portion of the projection, the progressively expanding portion and / or the biased portion, has an average roughness. surface measured in 3 dimensions (Sa) in the range of approximately 0.000025400-0.0012700 millimeters (1-50 μ inches), 0.000025400-0.0012192 millimeters (1-48 μ inches), 0.00017780-0.0010922 millimeters (7-43 μ inches), 0.00050800 -0.0012700 millimeters (20-50 μ inches), 0.00050800-0.0011430 millimeters (20-45 μ inches), 0.00063500-0.0011430 millimeters (25-45 μ inches) 0.00076200-0.0011430 millimeters (30-45 μ inches), 0.00050800-0.0010160 millimeters (20-40 μin) and 0.00076200-0.0010160 millimeters (30-40 μin).

The biased portion comprises a biased cutting surface having the outer diameter. The outer diameter of the biased cutting surface is at least about 0.0254 centimeters (0.01 inches) smaller than the outside diameter of the protruding portion and not less than the minimum diameter so that it is reduced although the frictional contact between the biased cutting surface and the metal container is not eliminated. The outer diameter of the biased cutting surface is dimensioned for. minimize collapse, fracture, wrinkle and all other physical defects, which could occur during expansion. In some embodiments, the diameter of the biased cutting surface is approximately 0.01905 to 0.0889 centimeters (0.0075 to 0.035 inches) smaller than the outer diameter of the protruding portion. In other embodiments, the diameter of the biased cutting surface is approximately 0.0254, 0.0508, 0.0762 centimeters (0.01, 0.02 or 0.03 inches) less than the outer diameter of the protruding portion.

In some embodiments, the working surface of the expansion die is dimensioned, so that when it is inserted into the metal container, the entire projection and at least a portion of the biased portion enter the metal container and the projection causes the diameter to expand at least a portion of the container.

In another embodiment, a die for decreasing the diameter of a metal container comprises a work surface configured to decrease the diameter of the metal container having a closed bottom portion.

The work surface comprises: a neck radius portion, a flange radius portion and a protrusion. The inner diameter of the projection is the minimum diameter of the matrix.

In some modalities, at least the portion of the • Working surface of the die for decreasing the diameter of a metal container has a surface finish that has a maximum ratio of the closed vacuum area in the range of approximately one of 1-30%, 4-26%, 10- 26%, 10-20%, 10-15% and 12-15%. In some embodiments of the matrix for decreasing the diameter of a metal container, at least the portion of the projection has a surface finish having a maximum ratio of the closed vacuum area in the range of approximately one of 1-30%, 4 -26%, 10-26%, 10-20%, 10-15% and 12-15%. In some embodiments of the matrix for decreasing the diameter of a metal container, at least the section of the neck radius portion has a surface finish having a maximum ratio of the closed vacuum area in the range of approximately one of 1. -30%, 4-26%, 10-26%, 10-20%, 10-15% and 12-15%. In some embodiments of the matrix for decreasing the diameter of a metal container, at least the section of the flange radius portion has a surface finish having a maximum ratio of the vacuum closed area in the range of approximately one of 1. -30%, 4-26%, 10-26%, 10-20%, 10- 15% and 12-15%.

In some embodiments of the matrix for decreasing the diameter of a metal container, the portion of the work surface, which includes a portion of the neck radius portion, the shoulder radius portion and / or the projection, has a closed volume of standardized vacuum in the range of approximately one of 1-2000 mm3 / m2, 9-1674 mm3 / m2, 33-388 mm3 / m2, 100-300 mm3 / m2, 100-250 mm3 / m2, 125- 250 mm3 / m2, 150-250 mm3 / m2 and 155-231 mm3 / m2.

With respect to the die for decreasing the diameter of a metal container, a projection is the portion of the working surface of an expansion die having the smallest inner diameter that contacts a section of a container. It is possible that the matrix has multiple sections, where each section has a projection, each projection has a different internal diameter. The projection having the larger inner diameter travels further into the container than the projection having the smaller inner diameter.

In some embodiments, the length of the die projection for the diameter decrease of a metal container is approximately 0.0508 to 0.2032 centimeters (0.02 to 0.08 inches). In other embodiments, the length of the protrusion of the die for decreasing the diameter of a metal container is approximately 0. 0762 to 0.1778 centimeters (0.03 to 0.07 inches). In still other embodiments, the length of the die projection for decreasing the diameter of a metal container is approximately 0.1016 to 0.1524 centimeters (0.04 to 0.06 inches). In one embodiment, the length of the die projection for the diameter decrease of a metal container is approximately 0.1016 centimeters (0.04 inches). In one embodiment, the length of the die projection for the diameter decrease of a metal container is in the range of the linear contact of a continuous radius to 0.0254 centimeters (0.01 inches).

The neck radius portion is a portion of the recess matrix that forms a radius in the container immediately adjacent the neck or to the portion of the container having its diameter decreased by a projection of the matrix.

The flange radius portion is a portion of the recess matrix that forms the radius in the container that is being decreased adjacent a radius of the neck.

In some embodiments of the matrix for decreasing the diameter of a metal container, the matrix has a relief, wherein the projection lies between the neck radius portion and the relief. In some embodiments of the matrix for decreasing the diameter of a metal container, the transition between the projection and the relief is combined. In some embodiments, at least a portion of the relief has the average surface roughness (Ra) of approximately 0.00020320 to 0.00081280 millimeters (8 to 32 μ inches). In some embodiments, at least the section of the flange radius portion has an average surface roughness (Ra) of approximately 0.000050800 to 0.00015240 millimeters (2 to 6 μin). In some embodiments, at least the section of the neck radius portion has an average surface roughness (Ra) of approximately 0.000050800 to 0.00015240 millimeters (2 to 6 μ inches). In some embodiments, at least the portion of the projection has the average surface roughness (Ra) of approximately 0.00020320 to 0.00081280 millimeters (8 to 32 μ inches). In some embodiments, at least the portion of the work surface, which includes at least a portion of the projection, the shoulder radius portion, the neck radius portion and / or the relief has an average surface roughness measured at 3. dimensions (Sa) in the range of approximately 0.000025400-0.0012700 millimeters (1-50 μ inches), 0.000025400-0.0012192 millimeters (1-48 μ inches), 0.00017780-0.0010922 millimeters (7-43 μ inches), 0.00050800-0.0012700 millimeters ( 20-50 μ inches), 0.00050800-0.0011430 millimeters (20-45 μ inches), 0.00063500-0.0011430 millimeters (25-45 μ inches) 0. 00076200-0.0011430 millimeters (30-45 μ inches), 0.00050800-0.0010160 millimeters (20-40 μ inches) and 0.00076200-0.0010160 millimeters (30-40 μ inches).

The dimensions of the relief are proportioned to reduce the frictional contact with the metal container and the deburring matrix, once the metal container has been lowered through the projection and the extraction mechanism. Therefore, in some embodiments, the relief in conjunction with the Ra of the recessing surface, contributes to the reduction of frictional contact between the recessing die wall and the metal container being recessed, where the frictional contact Reduced maintenance performance of lowering while reducing the incidence of collapse and improves the release of the metal container. In one embodiment, the relief extends toward the deburring matrix wall at least 0.0127 cm (0.005 inches) measured from the base of the projection. The relief could extend along the direction of recess (along the y-axis) the total length of the upper portion of the metal container that enters the recess matrix to reduce the frictional clutch between the metal container and the deburring die wall in order to reduce the collapse incidence that still maintains the deburring performance. The relief comprises a relief surface, where the The inner diameter of the relief surface is at least about 0.0254 centimeters (0.01 inches) larger than the inner diameter of the protruding portion and the inner diameter of the relief surface is not larger than the maximum diameter so that it is it reduces although the frictional contact between the side wall of the metal container and the relief surface is not eliminated while maintaining the lowering performance when the side wall of the metal container is lowered. In some embodiments, the diameter of the relief surface is approximately 0.01905 to 0.0889 centimeters (0.0075 to 0.035 inches) larger than the inside diameter of the projection portion. In other embodiments, the diameter of the relief surface is approximately 0.0254, 0.0508, 0.0762 centimeters (0.01, 0.02 or 0.03 inches) larger than the inner diameter of the protruding portion.

In some embodiments, the work surface is dimensioned, so that when it is inserted into the metal container, the entire projection and at least a portion of the relief travel relative to the container in an axial direction and at least a portion of the relief travel beyond the top of the container.

In another embodiment, the expansion matrix for the facture of metal containers comprises a work surface configured to expand the diameter of a metal container that has a closed bottom. The work surface comprises a portion that expands progressively; and a salient. The outside diameter of the projection is the maximum diameter of the matrix. When the expansion matrix is expanding a metal container, at least a portion of the work surface has a surface having an area ratio in contact with the metal container with the area not in contact with the metal container in the container. range approximately one of 25-99%, 30-71%, 41-71%, 40-55%, 40-52%, 35-55% and 30-60%. In some embodiments, the expansion matrix of this paragraph has the same characteristics as the expansion matrices described above.

In another embodiment, the matrix for the facture of metal containers comprises a work surface configured to decrease the diameter of a metal container having a closed bottom part. The work surface comprises: a neck radius portion, a flange radius portion and a protrusion. The inner diameter of the projection is the minimum diameter of the matrix. When the die is decreasing the metal container, at least a portion of the work surface has a surface having an area ratio in contact with the metal container with the area not in contact with the metal container in the range of about from one of 25-99%, 30-71%, 41-71%, 40-55%, 40-52%, 35-55% and 30-60%.

In another embodiment, a method of facturing a matrix for forming metal containers comprises: providing an expansion matrix for the facture of metal containers comprising a working surface configured to expand the diameter of a metal container having a closed bottom part; and blasting at least a portion of the work surface. The work surface comprises a portion that expands progressively and a projection. The outside diameter of the projection is the maximum diameter of the matrix.

In some embodiments, at least the portion of the projection is shot peened. In some embodiments, at least the portion of the portion that expands progressively is shot peened.

In some embodiments, the work surface is shot peened with precision balls that have a diameter in the range of approximately 0.1587-0.2381 centimeters (1 / 16-3 / 32 inch) and 0.1587-0.3968 centimeters (1/16) -5/32 inch).

In some embodiments, the shot-peened portion of the work surface has a surface finish that has a maximum ratio of the closed vacuum area in the range of approximately one of 1-30%, 4-26%, 10-26%, 10- 20%, 10-15% and 12-15%.

In some embodiments, the shot-peened portion of the work surface has an area ratio in contact with the metal container with the area not in contact with the metal container in the range of approximately one of 25-99%, 30-71. %, 41-71%, 40-55%, 40-52%, 35-55% and 30-60%. In some embodiments the percentage of area of the work surface that is shot peened is approximately one of 50-100%, 71-76%, 68-78%, 50-80%, 60-80% and 60-70%. In some embodiments, the air pressure used for the thrust of the precision balls while grinding the matrix surface is in the range of approximately 0.69-2.07 bar (10-30 psi), 1.03-1.38 bar (15 -20 psi), 0.69-1.38 bar (10-20 psi) and 1.03-2.07 bar (15-30 psi).

In another embodiment, a method of facturing a matrix for shaping metal containers comprises: providing a matrix for the facture of metal containers comprising a working surface configured to decrease the diameter of a metal container having a part bottom closed; and blasting at least a portion of the work surface. The work surface comprises: a neck radius portion, a flange radius portion and a protrusion. The inner diameter of the projection is the minimum diameter of the matrix. In some embodiments, at least the portion of the projection is shot peened. In some embodiments, at least a portion of the portion of bead radius is shot peened. In some embodiments, at least the portion of the neck radius portion is shot peened. In some embodiments, the work surface is shot peened with precision balls that have a diameter in the range of approximately 0.1587-0.2381 centimeters (1 / 16-3 / 32 inch) and 0.1587-0.3968 centimeters (1/16) -5/32 inch). In some embodiments, the shot-peened portion of the work surface has a surface finish that has a maximum ratio of the closed vacuum area in the range of approximately one of 1-30%, 4-26%, 10-26%, 10- 20%, 10-15% and 12-15%. In some embodiments, the shot-peened portion of the work surface has an area ratio in contact with the metal container with the area not in contact with the metal container in the range of approximately one of 25-99%, 30-71. %, 41-71%, 40-55%, 40-52%, 35-55% and 30-60%. In some embodiments the percentage of area of the work surface that is shot peened is approximately one of 50-100%, 71-76%, 68-78%, 50-80%, 60-80% and 60-70%. In some embodiments, the air pressure used for the thrust of the precision balls while grinding the matrix surface is in the range of approximately 0.69-2.07 bar (10-30 psi), 1.03-1.38 bar (15 -20 psi), 0.69-1.38 bar (10-20 psi) and 1.03-2.07 bar (15-30 psi).

All the above modalities are capable of being used when decreasing or expanding the metal container without the use of lubricant. All of the foregoing embodiments are suitable for use in any type of metal container that includes stretched aluminum and iron containers that have a closed integral bottom, i.e., a two-part container. In all the above embodiments, the metal comprising the metal container could be any metal known in the art including, but not limited to, aluminum and steel. The metal container could or could not have a dome. In some embodiments, the metal container is a one-piece metal container that has a closed bottom portion. In some embodiments, the metal container is comprised of multiple pieces of metal joined together.

A surface finish that has a maximum ratio of the closed vacuum area in the range of approximately one of 1-30%, 4-26%, 10-26%, 10-20%, 10-15% and 12-15% will be referred to as a "textured surface" hereafter. The open vacuum volume and the closed vacuum volume are as characterized by WinSam® (Surface Analysis Module for Windows) as described in ("Surface Characterization in Forming Processes by Functional 3D Parameters," S. Weidel, U. Engel, Int. J. Adv. Manuf. Technol. (2007) 33: 130-136), which is incorporated herein by reference.

In one embodiment, the textured surface is created in the doubling and expanding dies by means of shot blasting with precision ball bearings to create a smooth though undulating texture. Blasting involves the thrust of precision balls with a hardness larger than the die to create ripples on the tool surface. The design of the finished or finished surface depends on the size and hardness of the balls, the speed of the air jet process, and the number of repetitive beats against the matrix. For purposes of this description, a precision ball is a ball having a diameter that varies by no more than about 1% The tool surface that is smooth though not flat, is able to reduce friction without excessive generation of debris or tool wear. The reduced friction is due to the reduced contact area between the die and the metal container. The contact area is as characterized by WinSam® (Surface Analysis Module for Windows) as described in ("Surface Characterization in Forming Processes by Functional 3D Parameters," S. Weidel, U. Engel, Int. J. Adv. Manuf. Technol. (2007) 33: 130-136), which is incorporated herein by reference. Reduced friction allows metal containers to be expanded or reduced to a greater degree in a single stroke of a matrix expansion or in a lowering matrix without damaging the container. The damage includes wrinkling, fracturing, forming lines, collapsing the metal container or anything that diminishes the appearance of the metal container.

Some embodiments of this invention consider the topography of the textured surface using three dimensional surface parameters and aim to minimize the contact area of the tool with the work piece.

In some embodiments, the use of a textured surface in the expansion or lowering matrix could have any combination of the following advantages: maximizing the extent of metal shaping in a single stroke of the expansion or de-scaling matrix without damaging the container due to the decrease in friction, in this way, the number of metal forming steps is reduced and the amount of flash is reduced; reduce the starting weight required to meet the final specifications of the product dimension; eliminate the need to use lubricant when forming metal containers. In some embodiments, shot peening of a matrix with the precision balls results in a matrix that can form a flawless metal container more consistently than with a largely polished matrix.

Brief Description of the Figures Figure 1 represents a cross section of an expansion matrix having two projections; Figure 2 represents a partial cross section of the expansion matrix of Figure 1; Figure 3 represents a cross section of a matrix for decreasing the diameter of a metal container; Figure 4 illustrates the direction of metal flow; Figure 5 shows the internal diameter of a portion of the working surface of the deburring die once it has been shot peened as described above; Figure 6 includes a small field of visual images of the internal diameter of a portion of the working surface of the deburring matrix shown in Figure 5; Figure 7 shows the surface topography of a surface to ground; Figure 8 is a graph showing the transverse average Ra of both of the shot peened surface and the land surface shown in Figures 5-7; Figure 9 shows the surface topography of the shot peened work surface of an expansion matrix; Figure 10 shows the surface topography shown in Figure 9 with the corresponding line profiles showing the depth and height of the indentations; Figure 11 shows the support area curve of the shot peened work surface shown in Figures 9 and 10; Figure 12 shows the amount of the forming charge of an expansion matrix having a shot peened work surface placed in a metal container during expansion of the container; Figure 13 shows the forming energy of an expansion matrix having a shot-peened work surface; Figure 14 shows the energy due to friction against the surface support area with respect to the non-shot peened surface; Y Figure 15 shows the energy due to friction against the surface support area with respect to the shot peened surface.

Description of the invention An example expansion matrix 10 is shown in Figures 1 and 2. A working surface 12 is also shown comprising a progressively expanding portion 14 and a projection 16. A skew 18 also it is illustrated.

An example matrix 30 having a work surface 32 configured to reduce the diameter of a metal container is shown in Figure 3. The work surface has a neck radius portion 34, a flange radius portion 36 and a projection 38. A relief 40 is also shown.

In one example, the working surface of a deburring die was shot peened with Class 1000 balls of diameter 0.2362 centimeters (0.093 inches). The quality of the balls was enough to minimize the generation of dust or the fracture of the balls. Next, follow the analysis of the shot peening die.

· The internal diameter of the deburring matrix was processed using a right angle lancet.

• A replica of the internal diameter of the deburring matrix was taken at one end.

The topography and roughness data are from the replica.

• All the topography images of the replicas have been inverted to represent the real topography of the matrix surface • Definitions ° Sci is the retention rate of Central Fluid.

Sci > l indicates good fluid retention.

° Svi is the Valley Fluid retention index. 0 < Svi < 0.2 with a high Sci indicates a good fluid retention in the valley areas.

° Vcl is the closed volume of vacuum that indicates the volume of vacuum on the surface available to trap fluids ° Vop is the open volume of vacuum that indicates the volume of vacuum on the surface that allows the fluid to escape.

• Instruments - Topography - NanoFocus μ ?? t? I • A 20X objective is used that provides a field of view (FOV) of 0.8 X 0.8mm.

· The topography of large field of vision (LFOV) of 5. 5 X 2.15mm.

Figure 4 illustrates the direction of the metal flow in relation to the following topographic images.

Figure 5 shows the internal diameter of a portion of the working surface of the deburring die once it has been blasted as described above.

Figure 6 includes the small field of view images of the internal diameter of a portion of the working surface of the recess matrix shown in the Figure 5.

The surface characteristics of the working surface of the deburring matrix after blasting were as follows: Average Sa = 0.00047752 millimeters (18.8 μin); Sci average = 1.63; Svi average = 0.11; Average Vcl = 72.2 mm3 / m2; Average Vop = 1965 mm3 / m2.

Figure 7 shows a non-blasted surface to earth. The surface characteristics of the surface shown in Figure 7 were as follows: Average Sa = 0.00052070 millimeters (20.5 μin); Sci average = 1.24; Svi average = 0.16; Average Vcl = 46.6 mm3 / m2; Average Vop = 2640 mm3 / m2.

Figure 8 is a graph showing the transverse average Ra of both of the shot peened surface and the surface to ground.

Conclusions • The shot-peened surface had almost double the closed volume of vacuum than the surface to earth with similar values of Ra.

• Fluid retention parameters Sci, and Svi indicate that the surface in the shot blasting die had a much better fluid retention than the surface to ground.

· The parameters of the closed vacuum volume Vcl and of the open vacuum volume Vop also show that the fluid retention is good for the shot peened surface in the deburring matrix.

• This indicates that the shot peened surface would have a much better tribological performance than a surface grounded.

In another example, an expansion matrix was shot peened with Class 1000 balls of 4 millimeters (0.1575 inches).

Figures 9 and 10 show the surface topography of a portion of the work surface after blasting. Figure 11 shows the support area curve of the shot-peened portion of the work surface.

In another example, the working surfaces of several expansion matrices were modified by shot blasting and the resulting effects on friction were compared with the baseline friction of a matrix surface that has been turned and slightly polished. The turned and slightly polished surface is not textured although it has a Ra value of 20.32 to 25.4 centimeters (8 to 10 inches). All other factors were kept constant (Pre-Shape, geometry of the tool, no air release was used, no lubrication was used). 10 samples were taken for each surface combination.

A "B Ball" is a precision ball that has a diameter of 0.1587 centimeters (1/16 of an inch). A "C Ball" is a precision ball that has a diameter of 0.2381 centimeters (3/32 of an inch).

Lubricant Surface Pre-Form Tool Work (Constant) (Constant) Turned and slightly polished (HT &P) Q cu Ball shot blasting 1/16 accuracy in ican the top of the turned surface Ti d H s rc d) and slightly polished? tn r-i 0 3 n (HT &P a ?? ') < D nJ tí 4-1? H \ 0 Ball C again shotblasting in the part] 03 superior of the l 1896 At4tumen. OJ -H £ ¡> > c Ball tool)) ttaserocen- '?' shot peened as is I r you CQ described (Ball? 'a | H in iiid R Rttt Foccoeesacierora: vor CO tí Ball 'C) -H ? CO B Ball shot blasting or (U Accuracy of 3/32 in n the top of N iió-iúll F EtnanspapxH the turned surface i) iibdu | H i-i tareucsapas and slightly polished P nJ S (HT &P a? B ') Changes in friction due to the tool surface of the changes in the forming energy were evident. The shaping energy totals were calculated from the Load versus Displacement data using a numerical integration technique.

The tool surfaces were characterized by Sa (the 3-D parameter for Surface Roughness), Vcl (The closed normalized vacuum volume), aclm (maximum ratio of the vacuum closed area (/ total measured area)) and percentage of contact area for each surface finish .

The Deformation Energy was calculated using the Finite Element Analysis that uses the Tool Geometry and Pre-Shape Sample given to provide the forming energy in a frictionless state. Then, the friction data were tabulated by subtracting the Deformation Energy from the totals of the forming energy to reach the Energy figures due to friction.

The results are provided with a Percentage Change in Friction Energy for each surface characterized in the percentage contact area.

Figure 12 shows the amount of the forming charge in the expansion matrix placed in the metal container. Figure 13 shows the forming energy. Figure 14 shows the energy due to friction against the surface support area with respect to the non-shot peened surface. Figure 15 shows the energy due to friction against the surface support area with respect to the shot peened surface.

Conversion Comparison of Energy without Lubrication / 6.6675 centimeters (2.625 inches) of Travel • The calculation of the standard deviation excludes the open circle result of the forming energy data.

• The addition of the 'C' ball finish to the top of a machined and slightly polished original tool surface was shown to reduce the forming power by 15 to 19 percent without the use of the lubricant.

• The use of a smaller diameter ball (the '?' Ball) was shown to reduce the forming energy by 4 to 10 percent without the use of the lubricant.

• The new blasting of the ball surface 'B' created previously with the ball 'C' did not produce a statistically significant change in the forming energy.

For the purposes of this description, terms such as superior, inferior, below, for above, under, envelope, etc., are relative to the position of a finished metal container resting on a flat surface, regardless of the orientation of the metal container during the manufacturing or forming stages or processes. A finished metal container is a metal container that will not undergo additional forming steps before it is used by the final consumer. In some embodiments, the upper part of the container has a hole.

Although the present invention has been described in considerable detail with reference to certain versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the versions contained herein.

All the features described in the specification, including the claims, summary and figures, and all steps in any method or process described, could be combined in any combination, except combinations where at least some of these features and / or steps are mutually exclusive. Each characteristic described in the specification that includes the claims, summaries and figures, may be replaced by alternative features that serve the same purpose, an equivalent or similar purpose, unless is expressly stated otherwise. In this way, unless otherwise expressly stated, each feature described is only an example of a generic series of equivalent or similar features.

Any element in a claim that does not explicitly state "the means" to perform a specific function or "stage" to perform a specific function does not have to be interpreted as a "means or step for" the clause as specified in 35 U.S.C. § 112

Claims

1. An expansion matrix for the manufacture of metal containers, characterized in that it comprises: a work surface configured to expand the diameter of a metal container having a closed bottom part, the work surface comprises: a portion that expands in shape progressive and a salient; wherein the outer diameter of the projection is the maximum diameter of the matrix; wherein at least a portion of the work surface has a maximum ratio of the closed vacuum area in the range of 1-30%.

2. The expansion matrix according to claim 1, characterized in that at least a portion of the projection has a surface finish having a maximum ratio of the closed vacuum area in the range of 1-30%.

3. The expansion matrix according to claim 1, characterized in that at least one section of the portion that progressively expands has a surface finish having a maximum ratio of the closed vacuum area in the range of 1-30%.

4. The expansion matrix according to claim 1, further characterized in that it comprises a biased portion in which the projection is located. between the portion that expands progressively and the biased portion.

5. A matrix for the manufacture of metal containers, characterized in that it comprises: a working surface configured to decrease the diameter of a metal container having a closed lower part, the work surface comprising: (i) a portion of radius of neck; (ii) a flange radius portion; and (iii) a projection; wherein the inner diameter of the projection is the minimum diameter of the matrix; wherein at least a portion of the work surface has a surface finish having a maximum ratio of the closed vacuum area in the range of 1-30%.

6. The matrix according to claim 5, characterized in that at least a portion of the projection has a surface finish having a maximum ratio of the closed vacuum area in the range of 1-30%.

7. The matrix according to claim 5, characterized in that at least one section of the neck radius portion has a surface finish having a maximum ratio of the vacuum closed area in the range of 1-30%.

8. The matrix according to claim 5, characterized in that at least one section of the flange radius portion has a surface finish having a maximum ratio of the closed area of vacuum in the range of 1-30%.

9. The matrix according to claim 5, further characterized in that it comprises a relief, wherein the projection lies between the neck radius portion and the relief.

10. A method of manufacturing a matrix for shaping metal containers, characterized in that it comprises: providing an expansion matrix for the manufacture of metal containers comprising: a work surface configured to expand the diameter of a metal container that has a closed lower part, the work surface comprises: (i) a portion that expands progressively; and (ii) a projection; wherein the outer diameter of the projection is the maximum diameter of the matrix; blasting at least a portion of the work surface.

11. The method according to claim 10, characterized in that at least a portion of the projection is shot peened.

12. The method according to claim 10, characterized in that at least a portion of the portion that expands progressively is shot peened.

13. The method according to claim 10, characterized in that the shot-peened portion of the Work surface has a surface finish that has a maximum ratio of the closed vacuum area in the range of 1-30%.

14. A method of manufacturing a matrix for forming metal containers, characterized in that it comprises: providing a matrix for the manufacture of metal containers comprising: a working surface configured to decrease the diameter of a metal container having a part bottom closed, the work surface comprising: (i) a portion of neck radius; (ii) a flange radius portion, - and (iii) a projection, wherein the inside diameter of the die projection is the minimum diameter of the die; and blasting at least a portion of the work surface.

15. The method in accordance with the claim 14, characterized in that at least a portion of the projection is shot peened.

16. The method according to claim 14, characterized in that at least a portion of the flange radius portion is shot peened.

17. The method according to claim 14, characterized in that at least a portion of the neck radius portion is shot peened.

18. The method according to claim 14, characterized in that the shot-peened portion of the Work surface has a surface finish that has a maximum ratio of the closed vacuum area in the range of 1-30%.