Can production tools and processes for controlling can weight, cost and dimensions

Abstract

The present invention teaches a process for measuring and grinding tools in can / cylinder production, reducing production downtime, saving costs, and enabling tool wear prediction. This process allows for more accurate tool inventory by tracking each tool in use and providing advanced diagnostics to the tool room, including not only out-of-spec alarms from QA but also predictive alarms for cans produced on each tool, in-spec can weight and wall thickness, tool size information used in production, tools in inventory, tools pulled from inventory, and other stock balance information. The present invention also teaches a system of equations for prioritizing grinding to maintain optimal tool inventory levels.

Description

[Technical field]

[0001] [Copyright Notice] A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by any party of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent document or records, but reserves all copyright rights whatsoever. (37 CFR §1.71(d))

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Non-provisional Patent Application No. 16 / 407,759, filed May 9, 2019, the contents of which are incorporated herein in their entirety.

[0003] The present invention relates generally to can making tools, particularly dies and punches used on bodymaker machines, and more particularly to bodymaker and associated tool packs and procedures for reducing can costs, controlling the weight and dimensions of cans produced, reducing scrap, reducing metal, improving production reliability, and reducing the possibility of shutdowns when regrinding punches and dies or replacing tool packs in the can making process.

[0004] [Statement regarding federally funded research] This invention was not made under a contract with or by any United States Government agency. [Background technology]

[0005] Modern methods of making cylindrical bodies such as aluminum cans use a machine called a "bodymaker" which repeatedly punches the cup, turning it into a finished can, minus any flanges, coatings, etc., with the lid being a separate piece / unit to be sewn on later.

[0006] Can design begins with the can specifications and requirements, the strength of the dome and column, and wall thickness, both thin and thick. These determine the bodymaker's can requirements for the punch and domer tooling design, along with the incoming metal thickness, cup design, and the bodymaker's die reduction.

[0007] Prior art Figure 9 is an older design of a body making machine. The reference numbers in Figure 9 are irrelevant to this patent application and may be ignored. Body makers must form the body of an aluminum can in a series of steps called drawing and ironing. These steps (redrawing, ironing, repeating) require a series of punches and dies for the various steps, and must be done at high speed to produce a can with a very precise weight / wall thickness of material. Too little material and the can will not meet the specifications and requirements, too much material and material, and therefore money, will be wasted in the can.

[0008] For a given size can, the weight of the can depends more on the wall thickness than on small variations in the can's diameter. Errors of less than 0.0001 inches can matter, so the tools used are measured with great precision.

[0009] The procedure can be generalized as follows. 1) The first punch changes the approximate cup shape, but after redrawing the can is still not the right size and shape. 2) The can is then punched through several (e.g., three) ironing dies, each of which progressively reduces the wall thickness. 3) The cans go through a QA step which checks wall thickness, can weight, regularity, etc. This step is incredibly important as even a small variation in can wall thickness can increase the cost of 100,000 cans (a fairly small number) by $10 or $20 due to excessive aluminum usage in the ironing process.

[0010] While this process seems simple at first glance, in reality there are additional factors that create a cascade of potential problems. In particular, dies and punches wear. As they wear, they change size and cans produced with the changed dies or punches fall outside of the acceptable weight range. This deviation is noted during QA, at which point production is typically halted while new dies and / or punches are replaced with the worn ones. Typically, with use, wear and regrinding, the inside diameter (ID) of the dies increases while the outside diameter (OD) of the punches decreases.

[0011] To make matters worse, in full-scale production, one die takes about two days (or just under a million cans), and with one punch and three or four dies for a full set, their wear at random and unrelated intervals increases the bodymaker's downtime for replacement by five times.

[0012] However, in practice, where die sizes come into play, a "tool set" is actually required that properly match dies and punches. As shown in Figure 3, the punch and die sets must match each other very closely, and even then, the change from each die to the next is a small reduction. Recall that even 0.0001 inch variations can be problematic. This means that the tool set must be a neat sequence of sizes. As shown in the hypothetical example of a 12 ounce container in Figure 3, a punch with an outer diameter of 2.6030 inches might be followed by a redraw die with an inner diameter of 2.6258 inches, and ironing dies with inner diameters of 2.6196, 2.6149, and 2.6090 inches. The problem is that when the redraw die begins to wear upwards at the ID and needs to be replaced, it must be replaced with one of the exact same size. If the replacement is not exactly the same size, the entire punch and die sequence cannot be used in production and must be replaced in its entirety.

[0013] Shutdowns are expensive, use more metal, and increase can and body costs. Unnecessary tool changes are costly and result in lost productivity. Furthermore, cans that are too thin to pass inspection are just as costly as cans that are too thick. It has been estimated that $0.10 to $0.20 is wasted per thousand cans due to improper thickness. Since production lines can produce millions of cans daily and most facilities have multiple lines running, this amount can add up quickly.

[0014] Since a typical die costs about $100, it is preferable to send the die / punch to the production facility's tool shop for regrind. Even this only allows a particular die to be used about a half dozen times, further complicating sizing. In particular, because a die can only be ground upwards in size, other dies in the same tool set must also be ground upwards to match when they come off the production line. Returning to the previous example, if a redraw die is ground by 0.0002 inches to make it a new larger diameter, the rest of the die set must also be ground larger. This results in a can / cylinder that is very slightly larger in diameter, but still has the required wall thickness at the end of production.

[0015] An analog of the prior art process for regrinding production dies is shown in FIG. 8. This process 802 is broadly similar to that used in the can production industry, but it is labeled as a prior art "analog" because various facilities tend to keep their exact operations private. This is not a flow chart, but rather a diagram of the tool room, inventory, grinding stock, and flow of tools through the production line. In particular, grinding stock 806 comprises the amount of used (or new) dies and punches that are placed on shelves in the tool room 804 available for regrinding. Of course, when grinding a given die, it is desirable to grind only the minimum amount necessary to return a given tool set to an orderly order, so the tool room can accumulate a certain amount of grinding stock 806 to more flexibly maintain a matched set. The machinist takes the selected tool from the grinding stock 806 to the grinder 810, where it is actually reground to the desired size. This is an estimate by the machinist based primarily on his experience in the industry and in the particular production facility. Tool room staff then size inspects 812 the die / punches and labels the dies with the exact size (to ten thousandths of an inch or less) so that the exact size is immediately known when the punch / die is placed in inventory 814. If a replacement tool is needed, a selection 816 is made from inventory 814 and the tool flows to production 818. Finally, the cans produced (flowing to quality assurance 820) are measured at some point where a can deviates due to tool wear on a particular bodymaker machine, triggering an alert 832 from QA to production. The line is (possibly) stopped and a new tool or a new set of tools is installed at the bodymaker.

[0016] The used tools / sets (in this case a set of four dies and one punch, or one die, or any other odd quantity, e.g. one die and four punches could virtually be removed at the same time) are then flowed back to the grinding inventory 806 in step 826.

[0017] Handling this step used to require ad-hoc hourly judgment by an experienced machinist in the tool shop. Typically, the tool room staff would have to remember, if they could remember, what sizes of tool sets are in use on the production line (or more likely, multiple production lines running at the same time). Then the tool room staff would literally look at the dies in the inventory and guess which sizes are most likely to wear out next and need to be replaced soon. Since the tool room requires a certain amount of time (hours) to regrind the dies, there is no economic possibility of doing it "on the fly". It is better to have the right tools on hand, so the machinist simply has the inventory and tries to anticipate the needs based on his experience, rather than doing it as the needs dictate.

[0018] There is one very specific item of known feedback: QA measurements of can weight and wall thickness (see line 832 near the bottom of the chart, from QA back to production). This information is collected frequently, and when weight or thickness (the two are obviously related) exceed limits, production line staff are notified that changes need to be made on that particular line. However, when die / punch changes are made and replacements disappear from inventory, the tool room becomes aware of this.

[0019] Rather, a process should be put in place that allows tool room staff to proactively know the amount of production already done on a given die, the exact tool size currently in production, and instantly receive QA alarms for out-of-spec cans, as well as information on the weight and wall thickness of cans that are being produced in-spec.

[0020] It is also desirable to have procedures in place in the toolroom to know what grindable stock is available and what sizes are likely to be needed for current production so that toolroom staff can balance the stock against known inventory levels. Summary of the Invention

[0021] General Overview This application is directly related to the improvements made possible by using the Bodymaker and associated tool packs and procedures, including but not limited to reduced downtime for tool changes, reduced scrap, improved metal usage by putting excess metal in the trim and selling it as scrap instead of returning it to the can if not needed, and reduced tool pack change / installation time associated with tool pack preparation. Additionally, this process can also be used to predict tool wear in order to change tools before an out of specification condition occurs.

[0022] The present invention teaches a process for measuring and grinding tools in can / cylinder production that allows for more accurate tool inventory keeping by tracking each tool in use and providing advanced diagnostics to the tool room, including not only out of spec alarms from QA but also predictive alarms for cans produced on each tool, on-spec can weight and wall thickness, information on tool sizes used in production, tools in inventory, tools pulled from inventory, and other stock balance information. The present invention further teaches a system of equations for prioritizing grinding to maintain optimal tool inventory levels and increase productivity.

[0023] According to the present invention, the act of selecting tools and putting them into production can be informed by many factors, including the QA department's ongoing or real-time findings on can weight and can wall thickness (and QA receives a can ID indicating which specific bodymaker machine the can came from). This allows for advance measurement of which dies or punches may be out of optimum (due to wear) before the product actually changes from the required specifications, i.e. before an out-of-spec alarm occurs. Another "feedback" is tool production data, which can also be used for tool selection. Additionally, as certain tools are removed from or added to the inventory, this helps provide stock balance information for the production team and tool room as they engage in tool selection.

[0024] The present invention further teaches that, in another embodiment, grinding tool work in the tool room can be more advantageously performed if a grinding schedule is created. This allows tool room staff to operate on numerical criteria when deciding which tools to remove from the grinding stock, grind, and return to the tool inventory. In one aspect, the tools that are pulled from the production machine and returned to the grinding stock may be accompanied by information about which tools they are, and furthermore, the tools that will be used thereafter may be known to the grinding scheduler. However, the available inventory level of tool stock ready for grinding provides a further advantage of the present invention. Using a simple equation (presented here), the tool room machinist can objectively determine the priority of the planned work based on the number of tools of a given size in the tool inventory, the preferred maximum and minimum values ​​of the inventory, and the number of tools of a given size used in production, and from these values, five additional values ​​can be determined: the deficit, the potential deficit, the desired amount of grinding, the priority level, and the priority number for that particular grinding.

[0025] Abstract of claims Thus, another aspect, advantage, object and embodiment of the present invention, in addition to those mentioned above, is to provide an improved method of producing cylindrical bodies on a production line having a bodymaker, a tool shop and a quality assurance station, the improved method comprising: providing a grinding stock, a tool inventory, and a tool selection station in a tool shop; Providing a first toolset to a bodymaker, the first toolset comprising a first plurality of tools including a first tool having a first size; the tool inventory including a second plurality of tools not being used by the bodymaker; redrawing and ironing a plurality of cylinders using a first toolset, the production line notifying a tool shop of the number of the plurality of cylinders produced using the first tools; a quality assurance station measures a first cylinder of the plurality of cylinders against a preset threshold can wall thickness and notifies a tool selection station of the can wall thickness and notifies both the production line and the tool shop if the first cylinder exceeds the preset threshold while the production line returns a first tool of the first toolset to grinding stock and replaces the first tool with a second tool pulled from a tool inventory, the second tool having a first size; Regrinding the first tool; Equipped with.

[0026] Thus, another aspect, advantage, object and embodiment of the present invention, in addition to those mentioned above, is to provide an improved method of producing cylindrical bodies on a production line having a bodymaker, a tool shop and a quality assurance station, the improved method comprising: providing grinding stock, a grinding scheduling station, and a tool inventory in a tool shop; Providing a first toolset to a bodymaker, the first toolset comprising a first plurality of tools including a first tool having a first size; the tool inventory including a second plurality of tools not being used by the bodymaker; redrawing and ironing a plurality of cylindrical bodies using a first toolset, the production line informing the tool shop of the number of the plurality of cylindrical bodies produced using the first tools and informing the grinding scheduling station of a size set of the first toolset being used at the bodymaker; a quality assurance station measures a first cylinder of the plurality of cylinders against a preset threshold for can wall thickness and notifies both the production line and the tool shop if the first cylinder exceeds the preset threshold, while the production line returns a first tool of the first toolset to grinding stock and replaces the first tool with a second tool pulled from a tool inventory, the second tool having a first size; a tool inventory notifying a grinding scheduling station of a number of tools in the tool inventory having a first size; assigning a priority to a task of regrinding the first tool using a number of tools in the tool inventory having a first size and a number of cylinders produced using the first tool and a size set of the first toolset; regrinding the first tool if the first tool has the highest priority in the regrinding schedule; Equipped with.

[0027] Thus, another aspect, advantage, object and embodiment of the present invention, in addition to those mentioned above, is to provide an improved method of producing cylindrical bodies on a production line having a bodymaker, a tool shop and a quality assurance station, the improved method comprising: providing a grinding stock, a grinding scheduling station, a tool inventory, and a tool selection station in a tool shop; Providing a first toolset to a bodymaker, the first toolset comprising a first plurality of tools including a first tool having a first size; the tool inventory including a second plurality of tools not being used by the bodymaker; redrawing and ironing a plurality of cylindrical bodies using a first toolset, the production line informing the tool shop of the number of the plurality of cylindrical bodies produced using the first tools and informing the grinding scheduling station of a size set of the first toolset being used at the bodymaker; a quality assurance station measures a first cylinder of the plurality of cylinders against a preset threshold can wall thickness and notifies a tool selection station of the can wall thickness and notifies both the production line and the tool shop if the first cylinder exceeds the preset threshold while the production line returns a first tool of the first toolset to grinding stock and replaces the first tool with a second tool pulled from a tool inventory, the second tool having a first size; a tool inventory notifying a grinding scheduling station of a number of tools in the tool inventory having a first size; assigning a priority to a task of regrinding the first tool using a number of tools in the tool inventory having a first size and a number of cylinders produced using the first tool and a size set of the first toolset; regrinding the first tool if the first tool has the highest priority in the regrinding schedule; Equipped with.

[0028] Thus, another aspect, advantage, object, and embodiment of the present invention, in addition to the above, is to provide a process for regrinding diametric cylindrical body making tools, including punches and dies used in can making, in a production facility having a quality assurance station, the process comprising: a) providing a tool shop with a grinding machine, a tool inventory, a grinding stock, and a tool selection station, the tool inventory including a first plurality of tools ready for use at a production facility, each tool in the tool inventory having an associated diameter, and the grinding stock including a second plurality of tools returned from the production facility, each tool in the grinding stock having an associated diameter, and there are a plurality of associated diameters of the tools; b) The minimum M of the tool for the first relevant diameter ^ setting a number; c) setting a maximum Mv number for the tool for the first relevant diameter; d) setting a threshold product diameter; e) measuring a first cylindrical body produced with a first tool at a production facility and, if the first cylindrical body exceeds a threshold product diameter, replacing the first tool in production with a second tool withdrawn from a tool inventory, the first and second tools having a first associated diameter; f) replacing the first tool in the grinding stock; g)M ^ subtracting the number A of tools in the tool inventory having the first relevant diameter from the first relevant diameter, thereby deriving a value of the deficit D; h) subtracting from Mv the number A of tools in the tool inventory having the first relevant diameter, thereby obtaining the grinding amount G q Deriving a value of I) the number P of tools in production having a first relevant diameter q Count and P q , subtracting the number of tools A in the tool inventory having the first relevant diameter from the total number of tools A in the tool inventory, thereby obtaining the potential shortage D p Deriving a value of j) Potential shortage D pif is greater than zero, assigning a first priority level to the first associated diameter; k) Potential shortage D p if D is less than one and the deficit D is greater than zero, assigning a second priority level to the first associated diameter; L) Potential shortage D p if D is less than 1 and the deficit D is less than 1, assigning a third priority level to the first associated diameter; m) For each member of a number of relevant diameters, A, M ^ , Mv, P q , D, G q , and D p repeating steps b) through l) until each of the values ​​of n) the potential shortfall D of each member of the plurality of associated diameters assigned the first priority level p , and the potential shortage D is compared until a priority number is assigned to each member of the plurality of related diameters that are assigned a first priority level. p from highest to lowest, with the highest receiving a priority number of 1 and the second highest receiving a priority number of 2; O) continuing to assign priority numbers in the same numerical order without starting over by comparing the deficit D of each member of the plurality of associated diameters assigned the second priority level and ordering each from highest to lowest in terms of deficit D; p) continuing to assign priority numbers in the same numerical order without starting over by comparing the associated diameter of each member of the plurality of associated diameters assigned the third priority level and ordering each with respect to diameter; q) selecting a tool selected for regrinding from the grinding stock, the tool selected for regrinding having an associated diameter that received the highest priority number; r) regrinding the tool selected for regrinding; s) removing the tool selected for regrinding from the grinding stock and adding it to the tool inventory; t) repeating steps g) through s); Equipped with. [Brief description of the drawings]

[0029] [Figure 1] FIG. 1 is a block diagram of a first embodiment of the present invention, showing a hypothetical toolset of four dies and one punch. [Diagram 2] FIG. 2 is an elevational view of a single cylinder at various stages of production at the bodymaker. [Diagram 3] FIG. 3 is a table showing a hypothetical pair of toolsets, both designed to produce cans or 12 ounce containers with a diameter of approximately 2.600 inches, producing thick walls with a thickness of approximately 0.0060 inches. [Figure 4] Figure 4 shows the four main areas of the production facility and several sub-areas with emphasis on the tool room, and is a process chart showing the movement of the tools (and alarms and information about the tools) as they pass through various parts of the facility. This shows a first embodiment of the invention having both tool selection and grinding scheduling. [Diagram 5] FIG. 5 shows a production facility with emphasis on the tool room and is a process chart showing the movement of the tools (and alarms and information about the tools) as they pass through different parts of the facility in a second embodiment using tool selection. [Figure 6] FIG. 6 shows a production facility with emphasis on the tool room and is a process chart showing the movement of the tool (and alarms and information about the tool) as it passes through different parts of the facility in a third embodiment using planned grinding scheduling. [Figure 7] FIG. 7 is a table illustrating grinding prioritization based on various factors as set forth in the formulas taught herein. [Figure 8] Figure 8 is an example of an analogue of a prior art process for tool handling and regrind used in a current production facility. This diagram does not represent the specific known process used in the facility. [Figure 9]Figure 9 is a prior art Bodymaker machine from a 1970s patent. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] Glossary As used herein, the term "grinding stock" refers to both worn and new tools available for grinding, and generally to the area of ​​the tool shop where they are stored.

[0031] The term "size inspection" refers to verifying that the reground tools are the exact dimensions required for a particular tool set and labeling the new exact size of the tool. This produces the "associated diameter" of the tool. Knowing the diameter of the tool is essential for proper production. Since tools come in a variety of sizes, in practice there are "multiple associated diameters" for most groups of tools. For example, the various diameters shown in Figure 3 or Figure 7.

[0032] As used herein, the term "tool" refers to at least one die or punch used in producing a cylindrical body, such as a can.

[0033] The term "tool set" refers to a group of dies / punches that are in close proximity of related size (e.g., as shown in Figure 3) and are likely to be used together on a single bodymaker.

[0034] The terms "tool inventory" or "inventory" or "available inventory level" refer to tools that are on hand, reground, sized, and ready to go into production as needed, or more generally to the area of ​​the tool shop where tools are stored when ready for production.

[0035] The terms "tool shop", "production" (or "production line"), QA or "quality assurance", and control refer to the four main areas of a production facility involved in tool selection, grinding, cylindrical body production, etc.

[0036] The terms "can" and "cylinder" may be used interchangeably, however, for the purposes of this application, the term cylinder includes but is not limited to cans, and thus not all cylinders are cans, and thus the present invention may be applied to more types of production than just cans. Many consumer goods are sold in cylindrical objects that are not cans, such as aluminum bottles and jars for cosmetics.

[0037] The term "Tool Production Level" refers to the size and number of each size of each type of tool used in production, such as "Die #16543 with a diameter of 3.1005 will run 1,234,567 cycles (or cans produced, strokes, etc.) after regrind", "Die #08765 with a diameter of 3.1004 will run 456,789 cycles after regrind, ..." and this information is sent to the Tool Selector in the Tool Shop. Also, "Tool Size in Production" can refer to the size of the tools that are in the Bodymaker at any one moment. This is the notification sent to the Grinding Scheduler in the Tool Shop.

[0038] The term "out of spec alarm" refers to a notification from the QA department to the production facility that a can is not within tolerances / thresholds (measured by wall thickness, can weight, or other parameters). These notifications may be known in the prior art to go from QA to production, and in the present invention may go directly to the tool shop for use by tool shop staff. This is somewhat similar to a real alarm in that it is expected to generate urgent action to bring production back to acceptable dimensions.

[0039] On the other hand, the term "predictive alarm" is a notification sent from the production facility to the tool shop about how many cans have been drawn or ironed on a particular tool. This is useful in that the longer a tool has been in production (measured in cans produced), the more likely it is that it will need replacement in the near term. This notification may be updated frequently in real time, or policies may dictate that notifications occur at predefined thresholds.

[0040] Stock balancing levels refer to a fairly subtle use of resources. It appears as the action of issuing tools of a certain size (i.e. a row in the chart in the image below) to bodymakers based on having a surplus of tools of that size in inventory. If you think of the outcome if all bodymakers in a factory are running the exact same size of tools, they will quickly run out of tools of that size, resulting in low inventory levels for those sizes and high inventory levels for other sizes. This unbalanced stock can lead to disruptions in production or it can force tool shops to hastily regrind a large number of tools of the same size. It would be more efficient if each bodymaker ran slightly different sizes, evenly distributed across the available size range. In the real world, bodymakers may not be set up to run different sizes evenly distributed across the available size range, so stock balancing addresses this by completely changing the bodymaker's toolset (if the change is needed anyway) to balance the stock.

[0041] Can weight / wall thickness and similar measurements indicate whether the can is within specification (i.e., whether the can walls are too thick or too thin). Thickness can be measured by weighing the can. The term "wall thickness measurement" can include the weight of the can, since the weight of the can depends on the wall thickness and the thickness of the parent material that goes into the can.

[0042] "Out of inventory tool" refers to a tool that has been selected for removal from inventory, that has been sent to production for use by the bodymaker, and that is no longer available in the inventory for the process of the present invention, and therefore must be removed from the inventory records. This is important because it can change the actual count in the inventory and can change the shortage or potential shortage level of the tool, which can increase the priority for regrinding additional tools of the same type and size.

[0043] "Available inventory level" has its usual meaning of indicating the number of tools that are available in inventory and ready to be moved into production if necessary.

[0044] As used herein, "actual" or "A" refers to the actual number of tools in the inventory.

[0045] "Minimum" or "M ^ " refers to the minimum level of tools that will be kept in the inventory per policy.

[0046] "Maximum" or "Mv" refers to the maximum level of the tool that will be kept in the inventory according to the policy.

[0047] "Quantity in production" or "P q " refers to the number of tools of a particular size actually used in production.

[0048] The “shortage” or “D” is calculated by dividing the inventory and production (P q ), both the production level and the minimum level, or the difference between the minimum and the actual, means that there are not enough tools on hand.

[0049] "Grinding amount" or "G q " refers to the difference between maximum and actual according to Equation 3 below.

[0050] "Potential Shortage" or "D p” is the quantity in production (P q ) and the actual difference.

[0051] Current production methods reduce downtime and production costs by making dies and punches more readily available and prioritizing them more efficiently, which reduces material consumption and increases uptime for the factory / production line / body manufacturer.

[0052] End of Glossary FIG. 1 is a block diagram of a first embodiment of the invention, showing a virtual toolset of four dies and one punch. FIG. 1 shows a toolset 100. This is because the order of sizes of the various tools in the toolset necessarily limits the options available to a production line / facilities. In particular, the redraw die 102, ironing die #1 (104), ironing die #2 (106) and ironing die #3 (108) must be in a closely ordered order of sizes, measured by ID, and the punch 110 must also match different sizes (obviously measured by OD). This is because cylindrical bodies, such as cans, are not punched in a single-step operation at the bodymaker. Instead, FIG. 2 shows an elevational view of a single cylindrical body at various stages of production at the bodymaker. The redrawn cup / can / cylinder 202a, 202b, 202c, 202d is processed, punched and ironed in stages, with each iteration moving closer to the desired tolerances for can weight (i.e., material cost) and can thickness (thickness partially determines weight). To achieve these small variations in can wall thickness, smaller and smaller changes in die and punch size are required.

[0053] Figure 3 is a table showing a hypothetical pair of toolsets, both designed to produce cans or 12 ounce containers (approximately 346ml) with a diameter of approximately 2.600 inches. It is immediately evident that the difference in size between the different dies follows a neat progression without any significant gaps, with the first die having a 2.6007 ID, the next die having a 2.6006, the next die having a 2.6005, etc.

[0054] The second row is for a second set of tools of approximately the same dimensions.

[0055] Therefore, the tools must be ground very closely to the size of the set used by the body manufacturer, which means that the tool set limits the choice of tools to replace if one tool wears out with use and needs to be replaced, which in mass production occurs within a day or two.

[0056] FIG. 8 is an example of an analogue of a prior art process for tool handling and regrinding used in a current production facility. This diagram does not represent any particular patented process used in any particular facility. The Tool Use / Grinding / QA process 802 can be thought of as beginning in the tool room 804 where, based on an operator's estimation of need, a tool is selected from the grinding stock 806 and goes from there to the grinding station 810 where it is prepared (by regrinding) for reintroduction into the tool inventory of the production line. Immediately after regrinding, it is measured and inspected (812) and the tool is labeled with its exact dimensions so that it will only be used in the tool set that it fits in the correct size order. Unless there is an immediate need to resume production, the tool does not go directly into production; instead, the tool typically joins the tool inventory 814 and awaits selection 816 into production 818.

[0057] Cylinders produced on the bodymaker where the tool is used are measured by tool room personnel 812. Typically, quality assurance initiates a rigorous measurement and return sequence. If a threshold value for can wall thickness or can weight is exceeded, QA 820 notifies production 818 that there is a problem 832. At that point production is underway and the worn tool is removed 826 from the bodymaker and returned to grinding stock 806.

[0058] Management 824 likely monitors QA information, moves cans, and orders new tool inventory as needed or assumed to be necessary.

[0059] Figure 4 shows the four main areas of a production facility and several sub-areas with an emphasis on the tool room, and is a process chart showing the movement of tools (and alarms and information about the tools) as they move through various parts of the facility. This shows a first embodiment of the invention which both selects tools and schedules grinding, with the goal of providing a more steady flow of dies and punches in the tool inventory, thereby avoiding the need to change tools more than necessary (changing one tool is quicker than changing an entire toolset).

[0060] To do so, it is helpful to have procedures in place to guide tool shop staff in their die regrind selections. Figure 4 shows a more complex flow of tools and signals from one part of the can plant to another that makes this possible.

[0061] There are four main parts to a production facility: the actual production facility / line itself, the tool shop, the quality assurance station, and administration. Note that a "station" can refer to a department or a single employee, a workroom where a particular tool is available, useful communication or automation equipment (telephone, computer), etc. The point of this invention is not to reinvent the entire production line, but to add one station / process (the grinding scheduling station) and regrind the tools in a systematic order rather than relying on the experience of the tool shop staff.

[0062] Thus, the tooling / grinding / QA process 402 operates on the premise of the tool room 404 , the production line 418 , and quality assurance 420 .

[0063] Grinding stock 406 may have multiple tools waiting to be regrinded, however the order in which they are regrinded can mean the difference between optimal production efficiency and unnecessary production stoppages, unnecessarily large tool inventories, wasted labor costs, and other problems.

[0064] The grinding schedule 408 is implemented according to a procedure that requires a high degree of cooperation between different stations / departments of the facility, based on information from the production line and the QA department, in particular information that allows for the creation of the grinding schedule and the prioritization of grinding stock on the schedule.

[0065] Grinding machine 410 is the station where the physical grinding of each tool occurs. Machinists at the grinding station have access to the grinding schedule, eliminating the need to quickly guess which tool size will most likely be needed.

[0066] Size Inspection 412 simply checks the actual size of each tool as it comes out of the grinding station and labels it with its exact dimensions, specifically the OD of the punch and the ID of the die. This is necessary because each tool must be used with a set of other tools of sequenced sizes. Thus, every tool has an associated diameter, tools in the grinding stock have multiple associated diameters, tools in the tool inventory have another multiple associated diameters, and tools actually used in production (at the bodymaker) have yet another multiple associated diameters.

[0067] The inventory 414 then receives the sized tools and, in contrast to known prior art, the addition of a unit of a given associated diameter to the inventory can be back-reported to the grinder scheduling station to reduce the priority level or priority number (discussed below with respect to FIG. 7) of that particular size tool. Also unique to the present invention, stock balancing information is forwarded and reported from the inventory to the tool selection station 416.

[0068] Tool selection station 416 is a more systematic process than the prior art since, in the present invention, it is informed by information received from production personnel as will be described in connection with the next steps of the present procedure.

[0069] The production line 418 sends the cylinders produced by the bodymaker using the tool to quality assurance 420, which takes measurements to verify that the product is within the tolerances / thresholds. However, in the present invention, QA 420 does not just alert production 418 if the can is out of tolerance (step 432). In the control 424 embodying the present invention, QA 420 also notifies the tool selection station 416 of the weight and wall thickness 440 of the can, even if the can does not exceed the threshold and is perfectly acceptable. Furthermore, when QA 420 alerts production 418 of a can that is above / below the threshold, QA 420 also sends the same notification 428 to the tool shop 404, a step that is also not found in the prior art.

[0070] Additionally, production 418 informs tool shop 404 of the actual tool sizes (multiple associated tool diameters and the number of tools of each different diameter) being used in production 438, which is not found in the known prior art. Additionally, production 418 proactively provides predictive information to tool shop 404 in the form of information regarding the number of cans produced by a given tool (step 430). This innovation is useful in allowing tool shop 404 to determine when a given tool has likely drawn over one million cans and will need to be replaced. The same information is provided to a tool selection station (step 434).

[0071] Stock balancing levels 436, detailing which tool sets should be used per size to maintain balanced usage of the various size ranges among the different bodymakers at the facility, are provided by the tool inventory station 414 to the tool selection station 416. The tool selection station 416 notifies the tool inventory 414 when tools are pulled from the inventory (step 442), which in turn notifies the grinding scheduling 408 of the available inventory levels (444).

[0072] The tool is then returned to the tool shop grinding stock 406 in step 426, but along with the tool itself, data about the tool is also sent (this could be considered two separate steps, but for clarity of illustration is shown as a single step).

[0073] The present invention can also be used in partial form.

[0074] Figure 5 shows the production facility with emphasis on the tool room and is a process chart showing the movement of the tools (and alarms and information about the tools) as they pass through different parts of the facility in a second embodiment using tool selection. Figure 5 shows a more complex flow of tools and the notifications that enable this from one part of the can plant to another.

[0075] A production facility has four main parts: the actual production facility / line itself, the tool shop, the quality assurance station, and administration. Note that a "station" can refer to a department or even a single employee, a workroom where a particular tool is available, any communication or automation equipment available (telephone, computer), etc.

[0076] Grinding stock 506 may have multiple tools waiting to be regrinded, however the order in which they are regrinded can mean the difference between optimal production efficiency and unnecessary production stoppages, unnecessarily large tool inventories, wasted labor costs, and other problems.

[0077] Grinding machine 510 is the station where the physical grinding of each tool occurs.

[0078] Size Inspection 512 simply verifies the actual size of each tool as it comes out of the grinding station and labels it with its exact dimensions, specifically the OD of the punch and the ID of the die. This is necessary because each tool must be used with a set of other tools of sequenced sizes. Also unique to the present invention, stock balancing information is forwarded and reported from the inventory to the Tool Selection Station 516.

[0079] Tool selection station 516 is a more systematic process than the prior art since, in the present invention, it is informed by information received from production personnel as will be described in connection with the next steps of the present procedure.

[0080] Production line 518 sends the cylinders to quality assurance 520 where measurements are taken to verify that the product is within tolerances / thresholds. However, in the present invention, QA 520 does not just alert production 518 if the can is out of tolerance (step 532). In control 524 embodying the present invention, QA 520 also notifies tool selection station 516 of the can's weight and wall thickness data 540, even if the can does not exceed the threshold and is perfectly acceptable. Furthermore, when QA 520 alerts production 518 of a can that is above / below threshold, QA 520 also sends the same notification 528 to tool shop 504, a step not found in the prior art.

[0081] Additionally, production 518 proactively provides forecast information to tool shop 504 in the form of information regarding the number of cans produced by a given tool (step 530). The same information is provided to the tool selection station (step 534).

[0082] The stock balancing level 536 is provided by the tool inventory station 514 to the tool selection station 516. The tool selection station 516 notifies the tool inventory 514 when a tool is withdrawn from the inventory (step 542).

[0083] The tool is then returned to the tool shop grinding stock 506 in step 526, but along with the tool itself, data about the tool is also transmitted (this could be considered two separate steps, but for clarity of illustration is shown as a single step).

[0084] FIG. 6 on the other hand shows a production facility with emphasis on the tool room 604 and a process chart showing the movement of the tool 602 (and alarms and information about the tool) as it passes through different parts of the facility in a third embodiment using planned grinding scheduling 608, with tool selection being nothing more than a movement from inventory 614 to production 618.

[0085] Grinding stock 606 is ready for grinding according to grinding schedule 608, and when an item reaches the highest priority number, it goes to grinder 610, is reground, inspected, sized, associated with a size 612, and placed in inventory 614. Inventory 614 alerts schedule 608 of inventory level 644.

[0086] The production line 618 sends forecast alarms / cans per tool 630 directly to the scheduling department 608, as well as notification of the associated diameters 638 currently being used in production.

[0087] Quality Assurance 620 routes out-of-spec alarms, both conventional production alarms (632) and innovative alarms, to the tool room 628, which of course routes the tool and tool data back to the tool in step 626.

[0088] The important thing is that all stages of production and tools work together, and some useful parameters can also be invented, notably:

[0089] 7 is a table showing grinding prioritization based on various factors as shown in the formulas taught herein. In particular, the "deficit amount", "potential deficit amount" and "grinding amount" can be derived and calculated based on statistics that can be collected across all departments sharing information as described herein.

[0090] "A" is the actual number of tools in the tool inventory available for production.

[0091] "M ^ " is the minimum level of tools to be kept in inventory according to policies developed by management, production, and the tool room using information from quality assurance.

[0092] "Mv" refers to the maximum number of tools to be kept in the inventory according to secondary facility policy.

[0093] Finally, the number of tools in use in production at any given moment, P q " refers to the number of tools of a particular size actually used in production.

[0094] Note that for each different size of tool (e.g. 2.6184, 2.6196, etc.), each of these numbers is largely independent, so there are actually multiple sets of numbers, each relating to a different associated diameter of the tool. And because tools are located in three main locations (grinding stock, tool inventory, and production), there are actually three sets of numbers for each size and each location. Grinding scheduling staff must keep track of many groups of numbers to compare and determine priorities.

[0095] It is now possible to derive new metrics.

[0096] "Shortage" or "D" refers to the inventory 414 and production (P q ), there are not enough tools on hand for both production 418 and the minimum level, or alternatively, as the difference between the minimum and actual number of tools, according to Equation 1 below: Equation 1 D=M ^ -A

[0097] For example, a policy may dictate a minimum of 3 tools of size 2.6184 (first row in Figure 7), but there are only 2 tools in the inventory, so there is a shortage of 1 tool. This shows that while a policy dictates that a certain minimum be kept in the inventory, there is a shortage when there is not enough stock to meet the minimum.

[0098] However, in practice, it has been found that this is not a top priority metric and additional work is required.

[0099] In particular, the tool sizes actually used in production and weighted to the number of each size used on the production line 418 were found to be nearly deterministic. This is because the short-term potential shortage “D p " and the quantity being produced (P q ) and the actual number in the tool inventory 414. Formula 2 D p =P q -A

[0100] This high-priority metric proves to be important in the short term and is the basis for the system to create priority levels, as well as to number the tool sizes in order of priority (see Figure 7, tool size 2.6182, priority number 1). Thus, the positive potential shortage D p Item sizes (relevant diameters) with p It is necessary to process in order from smallest to largest.

[0101] There is a shortage of D, but p Items without a D value have second-level priority, and second-level items are processed in order from highest to lowest D value after the first-level items.

[0102] As a third priority, items can be processed from largest diameter to smallest diameter, or other rules can be derived and used.

[0103] The number of items to be ground is also important. A tool room may run multiple tool grinds, assuming it is easier to repeatedly grind a single size tool than to adjust the grinding machine or other equipment to different sizes after each tool. In this case, the "grinding volume" or "G q " refers to the difference between the maximum number to keep in inventory and the actual number in inventory, according to Equation 3 below. formula 3 G q =Mv-A

[0104] On the other hand, in other embodiments, G q may be ignored in favor of updating the grinding schedule after each tool is ground, sent to inventory, returned from production, etc. In such an embodiment, the calculations may be re-run after each change in tool availability data.

[0105] Portions of this process may be automated or at least partially automated, i.e., alarms, transfer of information, etc. may be performed using a programmable computer having non-volatile memory programming that instructs it to perform some of these tasks, e.g., spreadsheets, automated QA measurements, or other portions.

[0106] The present disclosure is provided to enable one of ordinary skill in the art to practice the invention without undue experimentation, including the best mode currently contemplated and presently preferred embodiments. Nothing in the present disclosure should be construed as limiting the scope of the invention, which is susceptible to numerous modifications, equivalents, and substitutions without departing from the scope and spirit of the invention. The scope of the invention should be understood from the appended claims.

[0107] Methods and components are described herein. However, variations of the invention can be obtained using methods and components similar or equivalent to those described herein. The materials, articles, components, methods, and examples are illustrative only and are not intended to be limiting.

[0108] Although only a few embodiments have been disclosed in detail above, other embodiments are possible and the inventors intend these to be included herein. Specific examples are described herein for achieving more general goals that can be achieved in other ways. The disclosure is intended to be illustrative, and the claims are intended to cover any modifications or alternatives that may be predictable to one skilled in the art.

[0109] Having illustrated and described the principles of the present invention in exemplary embodiments, it should be apparent to one skilled in the art that the described examples are exemplary embodiments and that changes in arrangement and detail may be made without departing from such principles. Techniques of any example may be incorporated into one or more of any of the other examples. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. [Explanation of symbols]

[0110] Figure 1 100 Toolset 102 Redraw 104 Ironing Die #1 106 Ironing Die #2 108 Ironing Die #3 110 Punch Figure 2 202a, 202b, 202c, 202d Can / Cylinder Figure 4 402 Tool Use / Grinding / QA Process 404 Tool Room 406 Grinding Stock 408 Grinding Schedule 410 Grinding Station 412 Size Inspection 414 Inventory 416 Tool Selection 418 Production Line 420 Quality Assurance 424 Management 426 Tools and tool data back to tooling 428 Out-of-specification alarm goes directly to tooling 430 Predictive Alarms per Tool / Can 432 Out of Specification Alarm 434 Tool Production Level 436 Stock balance adjustment level 438 Tool size in production 440 Can Weight / Wall Thickness Measurement 442 Inventory Out Tool Alarm 444 Available Inventory Levels Figure 5 502 Tool Use / Grinding / QA Process 504 Tool Room 506 Grinding Stock 510 Grinding 512 Size Inspection 514 Inventory 516 Tool Selection 518 Production Line 520 Quality Assurance 524 Management 526 Tools and tool data back to tooling 528 Out-of-specification alarm goes directly to tooling 530 Predictive Alarms per Tool / Can 532 Out of Specification Alarm 534 Tool Production Level 536 Stock Balance Adjustment Level 540 Can Weight / Wall Thickness Measurement 542 Tool Out of Inventory Alarm Figure 6 602 Tool Use / Grinding / QA Process 604 Tool Room 606 Grinding Stock 608 Grinding Schedule 610 Grinding Station 612 Size Inspection 614 Inventory 618 Production Line 620 Quality Assurance 624 Management 626 Tools and tool data back to tooling 628 Out-of-specification alarm goes directly to tooling 630 Predictive Alarms per Tool / Can 632 Out of specification alarm 638 Tool size in production 644 Available Inventory Levels Figure 7 A. Actual Inventory M ^ minimum Mv max P q Quantity in production D Shortage amount G q Grinding volume D p Potential shortage Figure 8 - Prior art analogues 802 Tool Use / Grinding / QA Process 804 Tool Room 806 Grinding Stock 810 Grinding Machine 812 Size Inspection 814 Inventory 816 Tool Selection 818 Production Line 820 Quality Assurance 824 Management 826 Tool Returns to Tooling 832 Out of Specification Alarm

Claims

1. 1. An improved method for producing cylindrical bodies in a production line having a bodymaker, a tool shop, and a quality assurance station, which reduces production downtime, reduces costs, and allows for prediction of tool wear, said improved method comprising: providing a grinding stock, a tool inventory, and a tool selection station at said tool shop; Providing a first toolset to the bodymaker, the first toolset comprising a first plurality of tools including a first tool having a first size; the tool inventory including a second plurality of tools not in use at the bodymaker; redrawing and ironing a plurality of cylinders using the first toolset, the production line notifying the tool shop of the number of the plurality of cylinders produced using the first tools; the quality assurance station measures a first cylinder of the plurality of cylinders against a preset threshold can wall thickness and notifies the tool selection station of the can wall thickness and notifies both the production line and the tool shop if the first cylinder exceeds the preset threshold while the production line returns the first tool of the first toolset to the grinding stock and replaces the first tool with a second tool pulled from the tool inventory, the second tool having the first size; regrinding the first tool; Equipped with.

2. 1. A process for regrinding diameter cylindrical production tools, including punches and dies used in can manufacturing, in a production facility having a quality assurance station that reduces production downtime, reduces costs, allows for prediction of tool wear, and reduces production line downtime and production costs, said process comprising: a) providing a tool shop with a grinding machine, a tool inventory, a grinding stock, and a tool selection station, the tool inventory including a first plurality of tools ready for use at the production facility, each tool in the tool inventory having an associated diameter, and the grinding stock including a second plurality of tools returned from the production facility, each tool in the grinding stock having an associated diameter, and there are a plurality of associated diameters of tools; b) the minimum M of the tool for the first relevant diameter ＾ setting a number; c) setting a maximum Mv number for the tool for said first relevant diameter; d) setting a threshold product diameter; e) measuring a first cylindrical body produced with a first tool at the production facility and, if the first cylindrical body exceeds a threshold product diameter, replacing the first tool in production with a second tool withdrawn from the tool inventory, the first and second tools having the first associated diameter; f) replacing the first tool on the grinding stock; g) M ＾ subtracting the number A of tools in the tool inventory having the first relevant diameter from the first relevant diameter, thereby deriving a value of a deficit D; h) subtracting from Mv the number A of tools in the tool inventory having the first relevant diameter, thereby obtaining the grinding amount G ｑ Deriving a value of I) the number P of tools in production having said first relevant diameter ｑ Counting, P ｑ , where A is the number of tools in the tool inventory having the first relevant diameter, thereby obtaining a potential shortage D ｐ Deriving a value of j) The potential shortage amount D ｐ if is greater than zero, assigning a first priority level to the first associated diameter; k) The potential shortage amount D ｐ if D is less than one and the deficit D is greater than zero, assigning a second priority level to the first associated diameter; L) The potential shortage amount D ｐ if D is less than 1 and the deficit D is less than 1, assigning a third priority level to the first associated diameter; m) for each member of said plurality of relevant diameters, ＾ , Mv, P ｑ , D.G. ｑ , and D ｐ repeating steps b) through l) until each of the values ​​of n) the potential shortfall D of each member of the plurality of associated diameters to which the first priority level is assigned; ｐ until a priority number is assigned to each member of the plurality of associated diameters that is assigned the first priority level. ｐ from highest to lowest, with the highest receiving a priority number of 1 and the second highest receiving a priority number of 2; O) continuing to assign priority numbers in the same numerical order without starting over by comparing the deficit D of each member of the plurality of relevant diameters assigned the second priority level and ordering each from highest to lowest in terms of deficit D; p) continuing to assign priority numbers in the same numerical order without starting over by comparing the associated diameter of each member of said plurality of associated diameters assigned said third priority level and ordering each with respect to diameter; q) selecting a tool selected for regrinding from the grinding stock, the tool selected for regrinding having the associated diameter that received the highest priority number; r) re-grinding the tool selected for re-grinding; s) removing the tool selected for regrinding from the grinding stock and adding it to the tool inventory; t) repeating steps g) through s); Equipped with.

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