Metal Products And Methods For Forming Components Thereof
20190001390 ยท 2019-01-03
Inventors
- Robert E. Dick (Cheswick, PA, US)
- Jeremy N. Pepper (Canonsburg, PA, US)
- Barry E. Soxman (Tarentum, PA, US)
- Anthony J. Fedusa (Lower Burrell, PA, US)
Cpc classification
B21D51/40
PERFORMING OPERATIONS; TRANSPORTING
B44B5/00
PERFORMING OPERATIONS; TRANSPORTING
B21D51/2607
PERFORMING OPERATIONS; TRANSPORTING
B21D51/26
PERFORMING OPERATIONS; TRANSPORTING
B21D51/38
PERFORMING OPERATIONS; TRANSPORTING
International classification
B21D51/26
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Generally, the instant disclosure is directed towards various methods of EMF-forming workpieces and the resulting workpieces. More specifically, the instant disclosure is directed towards various embodiments of imparting EMF-features onto workpieces, where workpieces with resulting EMF-features are configured as metal containers.
Claims
1. A method is provided, comprising: a. positioning a workpiece adjacent to an inductor of an EMF device, wherein at least a portion of the workpiece is positioned between an inductor coil and a die; b. discharging a power source of the EMF device to generate an electromagnetic frequency via the inductor; and c. generating an electromagnetic force via the inductor, wherein the inductor is positioned such that the electromagnetic force acts upon the workpiece, and d. concomitant with the generating step, imparting an EMF-feature on the workpiece adjacent to the inductor and the die.
2. The method of claim 1, wherein the workpiece and inductor are placed adjacent to each other but not in direct contact with each other, so as to prevent arcing.
3. The method of claim 1, wherein imparting an EMF-feature comprises: a. threading an upper portion of the workpiece, wherein the workpiece is configured as a metal container and further wherein, the upper portion is the neck of a metal container; b. curling an upper portion of the top portion of the workpiece wherein the workpiece is configured as a metal container and further wherein the upper top portion is the open upper end of the metal container; c. embossing a bottom portion of the workpiece, wherein the workpiece comprises a metal container and further wherein the bottom portion comprises a dome; d. stamping a bottom portion of the workpiece, wherein the workpiece comprises a metal container and further wherein the bottom portion comprises a dome; and e. embossing the sidewall of the workpiece, wherein the workpiece comprises a metal container and the sidewall comprises a non-necked portion of the metal container.
4. The method of claim 1, wherein the EMF-feature is selected from the group consisting of: an asymmetrical feature, a symmetrical feature, a finish, a threaded configuration, a lug pattern, a structural feature, a carrier ring, a pilfer band, an imprinted feature, a stamped feature, a logo, a graphic, a text, a curl, a hem, a trim, and/or combinations thereof.
5. A method, comprising: a. disposing/positioning an inductor in electrical communication with a pulsed magnetic device, such that the inductor is configured to impart a magnetic force to at least a portion of: a sidewall, a bottom, or combinations thereof of a workpiece; b. energizing the inductor via a power source to a voltage potential via a transducer, a capacitor, and an induction coil configuration; c. imparting a pulsed electromagnetic frequency into the portion of the workpiece sufficient to impart a deformation in the workpiece adjacent to the inductor; d. directing the workpiece onto a support surface die, and e. imparting, via the support surface die and EMF frequency, an EMF feature configured onto the workpiece.
6. The method of claim 5, wherein the support surface die is selected from: a die, an imprinting stamp, and combinations thereof.
7. The method of claim 5, wherein the directing step is selected from the group consisting of: a. imprinting the workpiece with the pattern on the die; b. molding the workpiece with the pattern on the die; c. impacting the die with the workpiece; d. deforming the metal into the workpiece; e. engraving the workpiece; f. incising the workpiece; and g. combinations thereof.
8. The method of claim 5, further comprising after the imparting step, necking an upper portion of the workpiece via a forming operation.
9. The method of claim 5, further comprising trimming an upper end portion positioned proximate to the open end of a workpiece to provide a trimmed upper end.
10. The method of claim 5, wherein the workpiece is constructed from: aluminum, aluminum alloys, steel, steel alloys, and combinations thereof.
11. The method of claim 5, wherein the workpiece comprises an AA series aluminum alloy selected from the group consisting of: a 1xxx series aluminum alloy; AA1060; AA1070; a 3xxx series alloy; AA3104; AA3004; A 5xxx series aluminum alloy; AA 5182; AA 5052; AA5042; AA5352; and combinations thereof.
12. The method of claim 5, where the workpiece is a formed aluminum bottle with at least one EMF feature selected from the group consisting of: threads, lugs, imprinted portions of the body, imprinted portions of the bottom, carrier rings, carrier ring inserts, and combinations thereof.
13. The method of claim 5, wherein the workpiece thickness range for imparting EMF-features ranges from at least 0.003 to not greater than 0.039.
14. The method of claim 5, wherein the workpiece comprises a container with a sidewall thickness of at least 0.003 that is formed from a sheet having a thickness of at least 0.006.
15. A device comprising: a metal container configured with an EMF feature selected from the group consisting of: a thread configured along the upper portion of the metal container; a stamped feature on the body of the metal container; a stamped feature positioned on the bottom of the metal container, and combinations thereof.
16. The device of claim 15, wherein the workpiece thickness ranges from at least 0.003 to not greater than 0.039.
17. The device of claim 15, wherein the workpiece comprises a container with a sidewall thickness of at least 0.003 that is formed from a sheet having a thickness of at least 0.006.
18. The device of claim 15, wherein the workpiece is constructed from: aluminum, aluminum alloys, steel, steel alloys, and combinations thereof.
19. The device of claim 15, wherein the workpiece comprises an AA series aluminum alloy selected from the group consisting of: a 1xxx series aluminum alloy; AA1060; AA1070; a 3xxx series alloy; AA3104; AA3004; A 5xxx series aluminum alloy; AA 5182; AA 5052; AA5042; AA5352; and combinations thereof.
20. The device of claim 15, wherein the EMF-feature is selected from the group consisting of: an asymmetrical feature, a symmetrical feature, a finish, a threaded configuration, a lug pattern, a structural feature, a carrier ring, a pilfer band, an imprinted feature, a stamped feature, a logo, a graphic, a text, a curl, a hem, a trim, and combinations thereof.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
[0104] Reference will now be made in detail to the accompanying drawings and experimental examples section, which at least assist in illustrating various pertinent embodiments of the present invention.
EXAMPLES
Example 1: EMF FeatureThreading by Expansion
[0105] Approximately 25 samples underwent EMF-forming to impart an EMF-feature (Thread) onto the sidewall (threading by expansion). Utilizing the pulse magnetic device described in Example 7, EMF-features were imparted onto the workpieces. The samples/workpieces were metal container preforms of aluminum alloy 3104 having a package diameter of 59 mm and a sheet thickness of approximately 0.0212. The workpieces (e.g. neck completed) were configured with closed bottoms and a perimetrical sidewall extending up from the bottom of the metal container.
[0106] Utilizing the dies depicted in
[0107] In order to evaluate forming conditions, the voltage was varied: the highest voltage was 8 kV, and the lowest was 4 kV. The EMF-forming imparted/imprinted an asymmetrical feature (e.g. PET-type thread depicted in
[0108] The resulting EMF-feature (thread configurations) imparted on the upper, open end of the metal container (workpiece) were visually inspected for quality, crispness/depth of threads, wrinkling, fractures, or other observable characteristics. In evaluating these samples, it was observed that samples ran with the tooling as-received at 6.5 kV resulted in a large number of fractures, while samples run at 4 kV had very slight (insufficient) amount of EMF-feature/thread imparted onto it (e.g. and any runs above 4 kV resulted in fracturing).
[0109] Without being bound by a particular mechanism or theory, it was determined that a modification to the tooling would promote better imprinting of the EMF-feature (thread configuration) and reduce, prevent, and/or eliminate fractures in the EMF-feature. The sharp edges in the as-received die were modified.
[0110] Without being bound by a particular mechanism or theory, a representative listing outlining several before runs using the tooling as-received and comparing to two after runs (after the tooling was modified) confirm that the fractures observed in the thread pattern were likely attributable to the sharp edges in the die. Without being bound by a particular mechanism or theory, at no condition using the as received tooling was the resulting EMF-feature/thread both deep enough and fracture free. In contrast, after the tooling was modified, the EMF-feature was imparted/imprinted at the same, or higher, voltage with no resulting fracturing observed.
[0111] The working specification for this run was to provide an EMF-feature configured as a thread with a depth of: 0.0275+/0.005. It is noted that for the data depicted in the table, the thread depth was quantified by measuring the distance from the thread root to the overthread location (e.g. the minor diameter of the thread subtracted from the major diameter of the thread, quantity divided by two).
TABLE-US-00001 Thread Depth Voltage (deepest Before/After Thickness Potential measurement) Fracture # of Modification (in necked sample (kV) [inches] (Yes/No) pulses of tooling at thread region) 4 0.01220 No 2 Before 0.0164-0.01675 4.5 0.01140 Yes 1 Before 0.0164-0.01676 5 0.01620 Yes 1 Before 0.0164-0.01677 5.5 0.01965 Yes 1 Before 0.0164-0.01678 6 0.02170 Yes 1 Before 0.0164-0.01679 6.5 0.02250 Yes 1 Before 0.0164-0.01680 6.5 0.02265 No 1 AFTER 0.0164-0.01681 8 0.02410 No 1 AFTER 0.0164-0.01682
[0112] In order to modify the tooling a small radius (0.005) was machined into several sharp corners on the tooling. Results of EMF-features (threads) created after machining in small radius were observed to be fracture free and when measured, the threads fell within the desired depth specification. It is noted that prior to modification, fracture occurred at energy levels of 4.5 kV and above, while after modifying the tooling, no fractures were observed or detected at an operating voltage of 8.0 kV.
Example 2: EMF Forming Threading by Reduction (Segmented Die)
[0113] With this experiment, a sample was run on a collapsible, segmented die in order to evaluate EMF-forming (creating a thread on the workpiece) via reduction of the diameter. The pulse magnetic device from Example 7 was used in this formation, with an inductor coiled around the outside of the workpiece (adjacent to the outer sidewall) and the die configured within the container (e.g. adjacent to the inner sidewall). The workpiece was aluminum alloy 3104, having a package diameter of 59 mm and a starting sheet thickness of approximately 0.0186. The workpiece was hit with one EMF-discharge (magnetic field).
[0114] After EMF forming, the segmented die was removed from the inside of the workpiece via a puller device. Although the EMF forming worked to impart a thread configuration on the upper portion of the metal container, when visually observed, it was determined that the part would not meet commercial specifications for rigid packaging materials (e.g. aesthetics).
TABLE-US-00002 Thread Depth Thickness (deepest (in necked Voltage measurement) Fracture # of sample at Potential (kV) [inches] (Yes/No) pulses thread region) 10.5 0.0209 Yes 1 0.0159-0.0164
Example 3: EMF FeatureImprinted Logos
[0115] Utilizing the pulse magnetic device described in Example 7, approximately 12 samples underwent EMF-forming to impart an EMF-feature onto the sidewall. The samples had a preform diameter of 59 mm and a sidewall thickness (e.g. in straightwall portion of preform) of 0.00765 to 0.00785 drawn and ironed from sheet of approximately 0.0176 thick. The samples were metal container preforms (e.g. aluminum alloy 3104), configured with closed bottoms and a perimetrical sidewall extending up from the bottom of the metal container. The preform was configured as a closed-bottom cylinder.
[0116] Utilizing the set-up detailed in
[0117] Across the several runs, the voltage was varied and the die material was changed (steel vs. plastic) and the resulting logos imparted on the sidewall were visually inspected for quality, crispness/depth, wrinkling, fractures, or other observable characteristics. All samples in this experiment were hit with one-EMF pulse only.
[0118] In order to evaluate the metal containers having an EMF-feature, the samples were visually inspected and observed for definition of logos on the metal container, tightness of radii and depth of profiles on the container. Two different logos were used in this example, as depicted in
TABLE-US-00003 Fracture Voltage Potential (kV) (Yes/No) Pattern die material Logo Quality Comment 9 kV No graphic design conducting steel Die fully filled (all 4 samples - same as those later imprinted w/Alcoa Logo) 10.8 kV No Alcoa logo conducting steel Die fully filled (all 4 samples) 3.5 No graphic design non-conductive No definition/slight metal die movement 6 No graphic design non-conductive good definition, die not fully die filled 6.5 No graphic design non-conductive Graphic Design pattern die evaluated well 7 Yes graphic design non-conductive Failure of logo die 9 Yes graphic design non-conductive Failure of logo die 3.5 No Alcoa logo non-conductive No definition/slight metal die movement 6 No Alcoa logo non-conductive good definition, die not fully die filled 6.5 No Alcoa logo non-conductive Alcoa Logo at full depth die 7 No Alcoa logo non-conductive Alcoa Logo more defined, die tighter corners 9 Yes Alcoa logo non-conductive Failure of logo die
Example 4; EMF-Feature: Logo Forming on Dome
[0119] Utilizing the pulse magnetic device described in Example 7, a workpiece (e.g. dome, having a 59 mm package diameter, made of aluminum alloy 3104) underwent an EMF-pulse with a voltage sufficient to imprint a logo ALCOA onto the dome. An image of the resulting imprinted dome is depicted in
[0120] Upon visual inspection of the imprinted logo, the logo was observed to have some small fractions, with good penetration into the die.
Example 5: EMF FeatureCurl/Curling the Workpiece
[0121] Utilizing the pulse magnetic device described in Example 7, approximately 30 samples underwent EMF-forming to impart an EMF-feature (e.g. curl) onto the upper end (opening) of the workpiece. The samples were taken from metal container preforms (e.g. aluminum alloy 3104, configured as open ended cylinders necked into an aluminum bottle chimney and then cut/removed from the bottom closed end of the workpiece (e.g. having no closed lower end). The removal of the lower portion of the aluminum bottle perform was only for expediency to fit the top chimney portion into existing holding fixtures.
[0122] To curl the top of the preform, a base tool (flyer) was positioned between the lower portion of the workpiece chimney and the inductor coil. In this set of examples, the base tool (flyer) was configured as an actuator to undergo displacement in the EMF field (created via the inductor) and press the workpiece chimney onto the curling die/tool (positioned on the opposite end of the workpiece chimney), imparting a curl on the upper portion of the sample. For all samples in this set, the inductor was operated at 9 kV.
[0123] Various 3xxx series alloys and 5xxx series alloy were tested to evaluate whether the equipment in this configuration could impart a curl onto different alloys. This configuration of utilizing a base tool/flyer as an actuator for completing an EMF-operation on a container was validated.
Example 6: EMF OperationTrimming
[0124] Utilizing the pulse magnetic device described in Example 7, one open ended cylinder was iteratively trimmed via EMF (e.g. utilizing a voltage of 6.5 kV) on alternating ends with dies shown in
[0125] The sample was a 3104 aluminum alloy with a package diameter of 59 mm and thickness (in straightwall portion of preform) of 0.0082 to 0.0087. In this example, the workpiece was configured as an open ended cylinders necked into an aluminum bottle chimney then removed from the straight, lower portion of the preform (e.g. having no closed lower end). The removal of the lower portion of the aluminum bottle perform was only for expediency to fit the top chimney portion into existing holding fixtures. As trimming was completed, each trimming operation resulted in multiple shreds of metal collecting in the bottom of the apparatus/auxiliary assembly.
Example 7: Pulse-Magnetic Device (EMF Device)
[0126] A lab-scale pulse-magnetic device was configured as follows: Maximum Accumulated Energy: 10 kJ; Output Voltage Range: 1-17 kV; Short-Circuit Current: up to 800 kA; Capacity of the energy storage68 m.sup.3 F; Frequency: variable, up to 109 kHz; Inductance: 31 nH; Supply Voltage: 460-480 V AC, 60 Hz; and Peak Line Currents (2s): 60 A. During discharge, a pulse of electromagnetic frequency lasted for a duration of a few to several microseconds (e.g. 2 microseconds (is) to 10 microseconds long).
[0127] With reference to
[0128] In operating the pulse-magnetic device, the charging operation is sufficient to charge the energy stores to a predetermined level U.sub.0 and synchronously discharging into the inductor L1 in automatic mode. In this configuration, the characteristic discharge into the inductive load is a single, a periodic or oscillating pulse with the discharging current frequency determined by parameters of the inductor.
[0129] The Charging unit transforms the main voltage AC of 460 . . . 480 V to high voltage DC of 20 kV. Charging is performed via the charging current controller which uses the method of pulse-phase regulation of the voltage of the high-voltage transformer. In the process of charging, the opening angle of the thyristor Q1 in the power circuit changes smoothly. Charging of capacitors C1 . . . C4 is completed in accordance with the linear law which ensures efficiency and high resource of the pulse capacitors.
[0130] The capacitors C1 . . . C4 are charged by high voltage in the range of 1 . . . 17 kV through ballast resistors R1 . . . R4. When voltage on the capacitors achieves the predetermined levelU.sub.0, the Energy dosing unit stops charging by the command Stop and simultaneously starts the Trigger-pulse generator by the command Discharge.
[0131] The initiating pulse of 6 kV from the Trigger-pulse generator is configured to start dischargers SV1 . . . SV4 which synchronously discharge the energy storages into a common loadthe working inductor L1.
[0132] In the charging process, the pulse current flows through the inductor. Amplitude of this current is 10 to 500 kA, its duration is 10 . . . 1000 s depending on the level of the stored energy and parameters of the working inductor.
[0133] The energy which is stored by the Energy storage is smoothly dosed by varying the charge voltage: W.sub.0=(C.sub.0*U.sup.2.sub.0)/2, where C.sub.0total capacity of the energy storage, U.sub.0charge voltage.
[0134] Referring to
[0135] By design, the pulse magnetic device is comprised of the basic power unit, the remote control station, the technological table, and protective box. The power unit includes: the high-voltage rectifier, the charging transformer, the power transformer for the Trigger-pulse generator and the ballast resistors of the charging unit, with the capacitors of the energy storage configured and the Trigger-pulse generator also located in the unit.
[0136] The following elements of external connections are placed on the side surface of the pedestal of the housing: the lead-in of the supply network cable, the plug-and-socket for connection of the cable of the remote-control station, terminals for grounding wires of the power unit and discharging rod. The discharging rod is set close to the pulse magnetic device and is configured to connect to the power unit.
[0137] The clamping device with output terminals for connection of the inductor is placed on the front panel of the housing. The technological table for placement of the inductor and working tooling is mounted on the front panel of the power unit.
[0138] The Energy dosing blockA5 and Voltage displayA6 are located in the remote-control station. Controls, signal indicators, the kilovoltmeter of the current value of charge voltage are placed on the panel of the remote-control station.
[0139] In some embodiments, the pulse-magnetic device utilized in one or more aspects of the instant disclosure is configured to convert electrical energy, accumulated by the capacitive energy storage, to the electromagnetic field, arising in the inductor during discharge of the energy storage. For example, the electromagnetic field of the inductor induces eddy currents in the processed material (e.g. portion of the workpiece undergoing EMF forming). Interaction of the electromagnetic field of the inductor with eddy currents in the processed material (e.g. portion of the workpiece adjacent to the inductor) leads to strain work and pulse heating of the material. The lab-scale EMF forming device described herein was utilized in the examples (experimental section) described herein.
Example 8: EMF FeatureIncising Operation on Bottom
[0140] Utilizing the pulse magnetic device described in Example 7, 1 sample: the bottom of a drawn and ironed aluminum bottle (e.g. aluminum alloy 3xxx), was incised with a setting of 8 kV in one pulse. The package diameter was 2.75 and the sheet thickness was 0.050.
[0141] To incise the bottom, a flyer tool was positioned between the workpiece and the inductor coil and configured as an actuator to undergo displacement in the EMF field (created via the inductor) and press the tool with lettering secured therein into the bottom of the workpiece/aluminum bottle (e.g. bottom, outer surface of the workpiece). The resulting incised logo was visually inspected for quality. It was found that all letters imprinted against the workpiece, leaving a legible message, ALCOA ALUMINUM MADE IN THE USA on the bottom of the sample. The logo was visually inspected and confirmed to have an acceptable definition incised upon it (e.g. all letters were fully visible, fracture free).
[0142] While various embodiments of the present invention have been described in detail, it is apparent that modifications and adaptations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present invention.
REFERENCE NUMERALS
[0143] Container (e.g. closed-bottom, metal container, shaped can, bottle) 10 [0144] Upper portion 12 [0145] Open end (e.g. configured at top) 14 [0146] Upper rim/edge 16 [0147] Lower portion 18 [0148] Bottom 20 [0149] Base 22 [0150] Dome 24 [0151] Sidewall 26 [0152] Inner sidewall 28 [0153] Outer sidewall 30 [0154] Body (e.g. cylindrical) 32 [0155] Shoulder 33 [0156] Neck 34 [0157] Thread (e.g. thread configuration/lug pattern) 36 [0158] Carrier ring 38 [0159] Carrier ring outsert 40 [0160] Carrier ring lip (e.g. formed via EMF and configured to hold/secure carrier ring insert) 90 [0161] Imprint feature (e.g. on bottom/dome vs. on sidewall/body) 42 [0162] Vent slots (e.g. channels, grooves configured generally axially) 44 [0163] Individual thread/lug (e.g. individual raised ridges interspaced with/defined by valleys) 46 [0164] Individual valleys (e.g. configured between threads, to define individual thread(s)/lug(s) and thread/lug depth) 48 [0165] Pilfer band (configured to accommodate pilfer ring) 52 [0166] EMF-feature 50 [0167] Curl (e.g. or flange, or flare) 54 [0168] closure (lid, cover, cap) 56 [0169] Trimmed upper edge (e.g. of rim 16) 58 [0170] Pulsed-magnetic device 60 [0171] Inductor 62 [0172] Die(s) 64 [0173] Mandrel(s) 66 [0174] Base, support for mandrel 66 [0175] Spacer(s) 68 [0176] Clamp (e.g. auxiliary positioning apparatus/system) 70 [0177] EMF/pulse/magnetic field 72 [0178] Base/support to act as actuator 92 [0179] Mechanical attachment area on die(s) (e.g. configured on outer sidewall of upper portion of container) 76 [0180] Attachment components (e.g. screws) for die 78 [0181] Die for sidewall imprinting 80 [0182] Sleeve 82 [0183] Insert with logo 84 (graphic 84, text 84) [0184] Die with window 86 [0185] Window/cut-out 88 [0186] Electrical connection (inductor to remaining electrical components of pulsed magnetic device) 94