WO2000015364A1

WO2000015364A1 - Lubricant metering system

Info

Publication number: WO2000015364A1
Application number: PCT/US1999/020864
Authority: WO
Inventors: Jeffrey T. Simpson
Original assignee: Henkel Corporation
Priority date: 1998-09-17
Filing date: 1999-09-16
Publication date: 2000-03-23
Also published as: AU5919199A; WO2000015364A9

Abstract

Lubricating equipment (10) for supplying to mechanical equipment (12) an emulsion of oil-in-water with a consistent concentration of the dispersed oil phase includes a circulation system (14) extending to the mechanical equipment from reservoir (22) containing the emulsion. The lubricating equipment is especially adapted to be utilized in the lubrication of mechanical equipment for manufacturing aluminum cans. The quantity and percentages of neat lubricant and water being supplied to the reservoir is controlled by a programmable logic controller (40). The programmable logic controller adds water and/or oil based on the output of the mechanical equipment, e.g., the can count during normal operating conditions.

Description

LUBRICANT METERING SYSTEM

BACKGROUND OF THE INVENTION

This invention generally relates to a lubricant metering system More specifically, the present invention relates to controlling the volume and concentration of a lubricating mixture, preferably a coolant emulsion, to be used for lubricating equipment, such as lubricating equipment used with sheet metal or can forming operations. The present invention can be effectively used to control the concentration of neat lubricant and water supplied to a recirculating sump that feeds coolant emulsion to aluminum can cuppers, bodymakers, and trimmers. Metal forming processes rely on devices that apply friction to one or more surfaces of a workpiece for the purpose of reshaping the workpiece. Lubrication and temperature control must be provided. Exemplary processes that share these common needs include aluminum can manufacture, sheet rolling of steel and aluminum, body panel shaping, etc. Of these processes, aluminum can manufacture is possibly the most sensitive to changes in equipment and operation, because the number of units per hour is much higher than most other operations and the products have very thin walls. Aluminum can manufacturing lines are highly precise systems that do not tolerate unanticipated changes well.

Most beverage containers or cans are constructed of aluminum from two pieces, i.e., a one-piece can body with a lid attached thereto. These types of beverage containers or cans are typically manufactured using a draw-and-iron (Dl) process in which a tool exerts friction on the surface of an aluminum stock piece The heat generated by that friction and its magnitude is reduced by using an oil-in-water emulsion ("coolant emulsion") of an organic lubricant ("neat lubricant" when free of diluents, etc.) between the tool and the stock.

In a typical aluminum can manufacturing process, flat, coiled aluminum sheet metal is fed into a "cupper" where the sheet metal is stamped into a round disc and pressed into a shallow cup. See, e.g., Snyder US Patent No. 4,534,202. This shallow cup is then conveyed to a "bodymaker" where the shallow cup is converted with a series of punches and forming dies into a seamless can of extended length and decreased wall thickness.

The first die of the bodymaker is a "redraw" die that reduces the diameter of the cup to the eventual diameter of the finished can body. Subsequent "ironing" dies smooth and thin or

"iron" the side walls of the can body. As the side walls of the can body are thinned, material redistribution increases the can height to a height that is greater than the desired height of the finished can, with an irregular top edge. See generally, Meneghm et al. US Patent No. 5,460,024.

A trimming machine is used to cut the can to standard dimensions and leave a finished edge. Typically, the top edge of the can body is further processed by necking-in the open end. With or without necking-in, the open end of the can body is flanged. Further steps can include painting the outside and coating the inside of the can with a protective barrier material. ^~"

Throughout the forming operations, a coolant emulsion supplied to the tooling to lubricate the interface between the surface of the stock material and the various dies, punches, etc. of the equipment. Typical equipment configurations include a reservoir with a pump, coolant emulsion recovery units, and various recirculation lines with filters.

A certain amount of lubricant is lost during the forming process. In the prior art, an operator needed to monitor both the emulsion level as well as the ratio of lubricant to water in the emulsion, with the costs and fluctuations that accompany manual monitoring operations. There was a need to replace a human operator with control equipment.

Examples of some prior lubricating devices are disclosed in the following U.S. Patents and are herein incorporated by reference:

3,150,548 to Roberts 4,660,586 to Knapp et al. 3,298,212 to Cook 4,715,398 to Shouldice et al. 3,463,178 to Kirchmier 4,793,440 to Iseman 3,561 ,238 to Tetzloff et al. 4,836,003 to Blake 3,648,497 to Long, Jr. et al. 5,101 ,936 to Paredes et al. 3,709,012 to Larsonneor 5,282,376 to Steele et al. 4,091 ,894 to Lang 5,456,097 to Zakhary et al. 4,150,767 to Pitches et al. 5,497,852 to Little et al. 4,186,582 to Johannisson et al. 5,513,671 to Cortopassi et al. 4,284,670 to Kole 5,531 ,085 to Hayes 4,445,813 to Misra et al. 5,537,849 to Kawakami et al. 4,506,533 to Hessel et al. 5,555,756 to Fischer et al. 5,575,303 to Hulbert Wilson US Patent No 4,202,193 determines and controls the concentration of coolant emulsion in metalworking operations by directly measuring the density of a portion of the coolant emulsion flowing through the system Emulsion stability is measured by a change in density within the measuring cell if the sample is stopped from flowing and allowed to separate. Steele et al. US Patent No. 5,282,376 controls the emulsion composition in a steel rolling operation through computer information on the input information- type of material being rolled, the speed of the strip material, the load on the rolling mill, stand, and the drive motor power

Zakhury et al. US Patent No. 5,456,097 alleges improvements in coolant emulsion stability and concentration by introducing premixed coolant at a point immediately prior to the body forming devices rather than at a location before the emulsion system filter. Introduction of each component in preset proportions is controlled by a single level sensor in the reservoir.

Despite these devices, there continues to be a need for an improved lubricant metering device which is relatively easy to operate, retrofits easily into existing equipment, and requires only minimal operator involvement. It is also desirable to have a coolant emulsion that contains a relatively consistent composition from a desired set point concentration of neat lube. Significant or extended fluctuations below the desired concentration result in excessive friction between the tool and the workpiece leading to poor surface quality, accelerated tool wear, excessive film thickness leading to poor print quality, etc. Moreover, the neat lubricant concentration in a coolant emulsion is often adjusted to accommodate changes in tool surface, workpiece, lubricant composition, etc

It would be useful to have a lubricant metering system that would provide consistent coolant emulsion concentrations and allow for a variety of designated set points for the coolant emulsion concentration.

It is an objective of the present invention to accomplish at least one of the following objectives'

To provide a system which can automatically control the addition of lubricant and water to a sump or reservoir at a rate based on actual can production rates;

To provide a lubricant feed system which can be easily integrated into existing control systems and existing equipment; - To provide a lubricant feed system which is easy to install and operate, with a high degree of reliability, and/or a reasonable rate of return on capital

To provide a lubricant metering system which is relatively easy to adjust to meet changed manufacturing requirements for concentration within the coolant emulsion. BRIEF SUMMARY OF THE INVENTION In accordance with these and other objectives of the invention that will become apparent from the description herein, the present invention relates to a lubricant metering system that includes: a. a circulation system including a fluid reservoir; b. a water supply source that can selectively supply water to said reservoir; c. a neat lubricant supply source that can selectively supply a quantity of neat lubricant to said reservoir; d at least one sensor that detects product output from equipment to be lubricated and generates at least one production signal for said product output; and e. a controller that detects said at least one production signal and controls supply of water and neat lubricant to said reservoir in response to said at least one production signal.

Also provided is a method for controlling the supply of lubricant to equipment with a lubricant circulation system comprising a fluid reservoir that hold a lubricating mixture; a water supply source that can selectively supply water to said reservoir; a neat lubricant supply source that can selectively supply a quantity of neat lubricant to said reservoir; at least one production sensor that detects product output from equipment to be lubricated and generates at least one production signal for said product output; and a controller that detects said at least one production signal and controls supply of water and neat lubricant to said reservoir in response to said at least one production signal, said method including the steps of: a. sensing product output from said equipment and generating a product output signal, b. detecting said product output signal; and c. supplying said lubricating mixture from said reservoir to said equipment in response to said product output signal. The system and control scheme of the present invention permit automated control and monitoring of the coolant emulsion level and neat lubricant concentration based on actual output of the manufacturing operation at any of several locations within the process. Such a measuring technique and associated system for maintaining the neat lubricant concentration in the coolant emulsion provides a coolant emulsion of consistent properties leading to a more consistent manufacturing operation with reduced defects and more predictable product surfaces.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a diagrammatic view of a lubricant metering system in accordance with one preferred embodiment of the present invention;

Fig. 2 is a schematic diagram of the lubricant metering system illustrated in Fig. 1 which generally shows the electrical signals between the main control assembly and the various parts of the lubricant metering system;

Fig. 3 is an elevation view of the main system panel for the lubricant metering system illustrated in Fig. 1 ;

Fig. 4 is a schematic diagram of the main control system for the lubricant metering system illustrated in Figs. 1 and 2; and

Fig. 5 is a flow chart illustrating the program for the programmable logic controller of the lubricant metering system illustrated in Figs. 1 and 2.

Fig. 6 is a schematic diagram of the control system according to the invention. DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a lubrication system that can automatically supply a makeup lubricating mixture, preferably an oil-in-water emulsion known in the trade as a "coolant emulsion", in relation to the rate of actual production of a manufacturing line. For convenience, the lubricating mixture will be referred to herein as a "coolant emulsion" although it will be understood by those in the art that the specific form of the lubricating mixture can vary. In its preferred application, the system is directed to a system for supplying coolant emulsion to an aluminum can manufacturing line in response to remote sensor readings of the rate of can manufacture at the output of cupper, bodymaking, and/or trimming steps. The precise rate of water addition is based on water loss per unit information that is readily calculable by an engineer with no more than an ordinary level of skill in this art. The rate of lubricant and emulsifier (if used) are individually adjustable for introduction to the system with valve or pump rate settings that denote concentrations relative to the water flow rate. Sensor readings that allow water to flow will also switch on pumps for neat lubricant and any emulsifier, biocide, or other additive desired for circulation in the coolant emulsion.

One method for controlling the rate of coolant emulsion addition is with a pulse signal from the output counter of one or more of the manufacturing stations. Preferred stations include the cupper output lιne(s), the bodymaking section output lιne(s), and the washer output lιne(s). The production pulses are aggregated and sent to a control unit set to respond to changes in the production rate. A reduction in production should generate a proportional reduction in the rate coolant emulsion is pumped to the tools. An increase in production rate should generate a corresponding and proportional increase in coolant emulsion feed rate Because actual output is used, it is preferred that the coolant emulsion pump controllers should operate with as little delay as possible between the sensing of a changed production rate and changes in the flow rate of coolant emulsion to the tool from which the changed rate of production is sensed.

Alternatively, the coolant emulsion is supplied to the equipment tools, either continuously or intermittently based on the rate of unit production at the output end of the particular tool, at the output of a particular step in the manufacturing process, at the output of the entire process, or any combination of these.

It is within the scope of the invention to provide a plurality of controllable, coolant emulsion flow systems that control the flow of coolant emulsion to each of tool where coolant emulsion is desired. For example, a sensing subsystem could be used to control the flow of coolant emulsion to the cupper tools independent of the coolant emulsion flow to the bodymaking step.

The precise location for introduction of the neat lube, emulsifier, biocide, etc. is not critical so long as the injection site provides adequate mixing to emulsify the introduced materials

Suitable locations include a header downstream of the main coolant emulsion circulation pump or immediately upstream of a coolant emulsion injection port for a particular tool. Other locations will be readily determinable by those skilled in the art with an understanding of a particular manufacturing line.

A preferred aluminum can manufacturing lubrication system that incorporates the control system of the present invention is conveniently described with reference to the attached figures. Where possible, similar devices are given the same reference number. Lubricant metering system 10 supplies coolant emulsion to can making equipment 12 that includes cuppers, bodymakers and trimmers. Generally, lubricant metering system 10 includes circulation system 14 which receives water from water supply 16 and "neat" lubricant (i.e., solvent-free and other diluent-free lubricant) from a lubricant supply 18. These fluids, i.e., water and lubricant, are supplied in controlled proportions to circulation system 14 which, in turn, supplies the coolant emulsion (an oil-in-water mixture containing up to about 10% organic lubricant) to equipment 12. Main control assembly 20 monitors circulation system 14 and regulates the addition of water and lubricant to circulation system 14.

In accordance with the invention, water and lubricant are supplied to circulation system 14 either individually or in emulsion form based on the actual production output of equipment 12.

The precise basis for calculating the production output of equipment 12.

In the manufacture of aluminum Dl cans, the coolant emulsion flow rate supplied to circulation system 14 can be based on the production rates of any or all of the cupper, bodymaker, trimmer and washer units. In other words, the lubricant metering system 10 counts the number of cans that are manufactured, and then adds water and/or neat lubricant to the circulation system

14 continuously at a rate proportional to the number of cans produced or in discrete volumes based on the production of a predetermined number of cans. Preferably, suitably positioned sensors detect when equipment 12 produces approximately 20,000 cans or some other, predetermined production number that can be correlated to a quantifiable loss of coolant emulsion absent replenishment A control signal is then generated to main control assembly 20 which adds predetermined amounts of water, neat lubricant, and any additives (e.g., emulsifiers, biocides, etc.) to circulation system 14. Lubricant metering system 10 will normally be set to control the ratios, intervals and quantities of water, neat lubricant, and additives that will be supplied to the circulation system 14 Lubricant metering system 10 is preferably provided with a manual override mode so that an operator can add neat lubricant from lubricant supply 18 as needed and/or desired. This manual mode also can be used when setting up lubricant metering system 10 and to establish and/or adjust the desired ratio of neat lubricant to water in the coolant emulsion.

Lubricant metering system 10 can be provided with various coolant emulsion level sensors to monitor the level of coolant emulsion flowing within circulation system 14 If the emulsion level in circulation system 14 is either higher or lower than a desired level, lubricant metering system 10 will add or withhold water and/or neat lubricant that is supplied to circulation system 14 until level sensors indicate that the emulsion level has returned to a normal operating range. Lubricant metering system 10 is also provided with neat lubricant supply level sensors and water pressure supply sensors to check the level of neat lubricant within a neat lubricant supply reservoir and water supply line, respectively In the event that the neat lubricant level and/or the water supply pressure falls below predetermined lower limits, these level sensors will generate a signal that stops equipment 12 and circulation system 14 As seen in Fig. 5, the addition of coolant emulsion to circulation system 14 is automatically regulated under normal operating conditions by main control assembly 20 without significant involvement of the operator

Referring again to Figs 1 and 2, circulation system 14 includes reservoir 22 in the form of a sump, header, barrel, bucket or other supply source containing coolant emulsion and conduit

24 Lube circulation pump 26 is connected thereto and conveys coolant emulsion from reservoir 22 to equipment 12 and then back to reservoir 22. Thus, circulation system 14 continuously supplies coolant emulsion to equipment 12, recovers coolant emulsion after use, and returns the collected coolant emulsion to a reservoir for reuse.

Reservoir 22 contains a sufficient amount of coolant emulsion to meet the needs of equipment 12 with a reasonable degree of surplus to accommodate at least minor fluctuations in supply and demand The precise coolant emulsion level for equipment 12 will depend on the specific type of equipment 12, and the determination of such levels is within the existing skill level by those in the art

Conduit 24 and lube circulation pump 26 convey coolant emulsion from reservoir 22 to equipment 12 More specifically, first end 28 of conduit 24 is disposed within the bottom of reservoir 22 so that pump 26 can withdraw all or substantially all of the coolant emulsion from reservoir 22 and force the coolant emulsion through circulation header 30 for distribution to sites and components of equipment 12 that require temperature control and lubrication

Conduit 24 then recovers used coolant emulsion and conveys the used coolant emulsion back to reservoir 22 via second end 32 of conduit 24 that is connected to circulation header 30. Unconsumed coolant emulsion from equipment 12 returns back to reservoir 22 via conduit 24 It will be apparent to those skilled in the art from this disclosure that conduit 24 refers to pipes and pipe systems, tubes of metal or nonmetallic material, a lube circulation header, and any other conveyance system that can guide coolant emulsion to and from reservoir 22 and equipment s

Preferably, water supply 16 is part of the main water supply system for the plant or building In such event, conduit 24 is coupled at one end to plant water supply 16 and has its other end positioned to deliver water to the reservoir 22. Accordingly, the water pressure of water supply 16 can be the same as that of the city water supply or can be elevated by the plant Main control assembly 20 regulates the flow rate of water supply 16 to reservoir 22 at a rate sufficient to provide an adequate volume of water for the sensed production rate and the time available for replenishing water in reservoir 22. The determination and settings necessary for such replenishment are set, within the existing level for one with an ordinary level of skill in this art, in accordance with the individual circulation system requirements, lubricant chemistry, and reasonable safety margins.

Main control assembly 20 also regulates the flow rate of neat lubricant that is supplied from lubricant supply 18 to circulation system 14. In the illustrated embodiment, neat lubricant from lubricant supply 18 is added into circulation system 14 via circulation header 30. Neat lubricant can also be added to circulation system 14 in a variety of ways: directly into reservoir 22, through a turbulent mixing zone, or into water supply 16

Main control assembly 20 is illustrated in Figs. 2-4 Main control assembly 20 includes main control panel 38, programmable logic controller ("PLC") 40, equipment operating sensors 42 (four shown in Figs. 2), emulsion level regulator 44, lubricant level regulator 46, solenoid valve 48, modulating valve 50, and lube injection pump 52 with ejector 54 Main control assembly 20 monitors the amount of emulsion in circulation system 14 via level regulator 44 which detects the level of emulsion within reservoir 22 and the output of equipment 12 via sensors 42. These signals are fed into main control assembly 20.

In the schematic illustration of lubricant metering system 10 as seen in Figure 2, the lines interconnecting components which are illustrated as dashes separated by circles indicate internal system link, i.e., software links, the dashed lines interconnecting components represent discreet electrical control signals generated by control system 20, and the solid lines with a pair of diagonal lines extending transverse thereto represent analog electrical signals.

In the preferred embodiment, water and/or lubricant are added at predetermined intervals and in predetermined amounts so that the lubricant metering system 10 operates with relatively minimal operator involvement. The addition of water to circulation system 14 is controlled by valves 48 and 50, while the addition of neat lubricant is controlled by lube injection pump 52. Of course, other types of control members can be used to control the addition of water and lubricant to circulation system 14 Mam control assembly 20 also monitors lubricant levels in lubricant supply 18 via level regulator 46 to warn the operator when the lubricant is below the normal operating level or to shut down lubricant metering system 10 when the neat lubricant level is below determined lower limits.

As seen in Figs. 3 and 4, control panel 38 has a power switch 64 for turning mam control panel 38 "on" or "off", a mode selection switch 66 for setting the mode of operation of system 10 between an automatic mode, an off mode and a timed mode, a feed rate switch 68 for adjusting ratios of neat lubricant to water when system 10 is set to the automatic mode, a set of timer buttons 70 for setting the amount of neat lubricant being added during the timed mode, and button 72 for manually adding a quantity of neat lubricant to circulation system 14 Control panel 38 is also preferably provided with indicator lights and/or test buttons to assist the operator in monitoring system 10. All discreet outputs or electrical signals from controller 40 are interlocked to the power switch 64 of control panel 38. In the illustrated embodiment, the total can count may be obtained by monitoring the can output of washers 76 via sensors 42 Of course, it will be apparent to those skilled in the art that the can count can be obtained from other product output sources (e.g., cuppers, bodymakers or trimmers) of the equipment, and usually may be most simply obtained by counting the strokes of the cupper press, which as the initial stage of manufacture accurately reflects the number of units in process.. Sensors 42 are preferably designed to send an electrical signal or pulse to controller 40 for representing the output of equipment 12. Each pulse is preset to reflect 100 cans/pulse. When the power switch 64 is turned to the ON position, the can counter with its default programming will count 20,000 cans before adding neat lubricant and water. The number of cans that will trigger adding neat lubricant and water can of course be set to some value other than 20,000. Preferably, a power ON delay timer (not shown) is used to provide a short delay (approximately 31 seconds) before opening either valves 48 or 50.

Mode selection switch 66 has three positions, i e., Auto/Off/Timed, for setting the operating mode of the lubricant metering system 10. When the mode selection switch 66 is set to the Auto mode position, lubricant metering system 10 is fully operated by the program of the controller 40 as seen by the flow chart of Fig. 5 Of course, the operator can add neat lubricant during the Auto mode by pushing the one shot button 72 The Timed mode position of mode selection switch 66 is a backup/manual mode which allows the operator to completely bypasses the controller 40 for manually adding neat lubricant from lubricant supply 18 to circulation system 14. The OFF position of mode selection switch 66 turns off the entire lubricant metering system

10

Programmable logic controller 40 can be, for example, an MicroLogix 1000 programmable controller/1761 -L32AWA which is manufactured by Allen Bradley, Inc. of Milwaukee, Wisconsin or a similar programmable logic controller. Controller 40 includes a microprocessor with programmed system operation logic that receives information on the status of lubricant metering system 10 for controlling the operation of lubricant metering system 10.

When controller 40 is set to the Auto mode position, the program of the controller 40 controls all aspects of lubricant metering system 10. In particular, the neat lubricant flow rate and the water flow rate are both adjustable via registers in controller 40. The neat lubricant con- centration of the emulsion is calculated by the program of the controller 40 which uses two ON timers 80 and 81 to regulate the addition of neat lubricant and water into circulation system 14 More specifically, the ON timer 80 controls the addition of neat lubricant by activating lube injection pump 52 for a predetermined amount of time based on the can count of washer 76, while ON timer 81 controls the addition of water by opening solenoid valve 48 for a predetermined set period of time based on can count of washer 76. The neat lubricant flow rate of lube injection pump 52 is preferably adjusted by changing the stroke of the lube injection pump 52. The water flow rate, on the other hand, is adjusted by modulating valve 50 which is opened by an electrical signal from controller 40. The aperture size of modulating valve 50 is set into the register of controller 40 to set a flow rate. In equipment used for manufacturing aluminum cans, the neat lubπcant to water ratio is normally preset at approximately 3% and the neat lubricant flow rate is set to 5.0 gallons per hour (GPH) and the water flow rate is set to 2.8 gallons per minute (GPM). However, it is desirable to be able to easily adjust the neat lubricant to water ratio. This can primarily be done by changing the setting of feed rate switch 68 which selects a preset ratio which was set into controller 40. Of course, the register settings of the controller 40 can also be adjusted to change these settings of feed rate switch 68

Preferably, feed rate switch 68 of control panel 38 is a rotary switch which is preferably provided with ten different settings for changing the neat lubricant to water ratio being added to circulation system 14 during the Auto mode. For example, the preferred 3% setting of neat lubricant to water ratio is preferably the fifth preset position to allow the operator easily to decrease or increase the neat lubricant to water ratio without having to reprogram the programmed logic in the PLC. In particular, in the Auto mode, the neat lubricant to water ratio can be set to four different settings which decreases the percentage of neat lubricant to water ratio from the preferred 3% setting Also, switch 68 has five different settings in which the neat lubricant to water ratio can be increased from the preferred 3% setting. In order for the program of controller 40 to regulate the amount of neat lubricant and water being added to circulation system 14 in the Auto mode, the following conditions have to be met. (1 ) the mode selection switch 66 of the control panel 38 must be in the Auto mode position; (2) the sump master air of level regulator 44 must be turned on; (3) the lube master air must be turned on, and (4) the circulating pump 26 must be turned on.

When mode selection switch 66 is in the Auto mode position, the feed rate switch 68 can be set at any one of the ten neat lubricant to water ratios The percentage of neat lubricant to water in the emulsion for each of the ten positions of feed rate switch 68 are preferably as follows: the first position is approximately 1.0 % neat lubricant; the second position is approximately 2.5% neat lubricant; the third position is approximately 2 0% neat lubricant; the fourth position is approximately 2.5% neat lubricant, the fifth position is approximately 3.0% neat lubricant; the sixth position is approximately 3 5% neat lubricant; and the seventh position is approximately 4.0% neat lubricant, the eighth position is approximately 4.5% neat lubricant; the ninth position is approximately 5% neat lubricant and the tenth position is approximately 5.5% neat lubricant. Accordingly, the increment between each of the preset positions of the feed rate switch 68, is preferably set at approximately 0.5%

The amount of neat lubricant and the amount of water being added is controlled by ON timers 80 and 81 when in the Auto mode. These ON timers 80 and 81 activate lube injection pump 52 and solenoid valve 48, respectively, for selected periods of time to control the neat lubricant to water ratio in circulation system 14 The 3% lube concentration of the fifth position is obtained by setting the two ON timers 80 and 81 for approximately 120 seconds each. All of the ratios of the other positions of feed rate switch 68 are accomplished by changing the presets of the two ON timers 80 and 81 to obtain the appropriate ratio as discussed below.

As mentioned above, the program of the controller 40 in the preferred embodiment, ob- tains a can count from sensors 42 which measure the output of four washers 76 of equipment 12 as discreet input pulses or electrical signals. The can counters or sensors 42 for counting the cans preferably send pulses to controller 40 which represent the number of cans being produced. Sensors 42 can be any conventional sensing means. Each pulse is preferably preset at 100 cans/pulse in the preferred embodiment. The program of controller 40 will count a predetermined number of cans (e.g., 20,000 cans) before adding any additional water from water supply 16 and/or neat lubricant from lubricant supply 18 to circulation system 14. Once the total can count reaches the predetermined number (e.g., 20,000 cans), the program of controller 40 will reset all can counters and start counting again as indicated in the flow chart of Fig. 5. For example, when the feed rate switch 68 is set to the fifth position, controller 40 sends a signal to the ON timers 80 and 81 to turn on the lube injection Dump 52 for approximately 120 seconds and turns on the solenoid valve 48 for approximately 120 seconds. These two ON timers 80 and 81 are set for approximately 120 seconds as a result of having the feed rate switch 68 of control panel 38 set in the fifth position (the preferred default position). The lube injection pump 52 is preferably pumping at approximately 5 gallons per hour (GPH) and the water flow rate is preferably approximately 2.8 gallons per minute (GPM). Of course, it will be apparent to those skilled in the art that the amount of time needed to obtain the 3% neat lubricant to water ratio will change depending upon the flow rates of the lube injection pump 52 and the flow rate of the water supply 16.

Lubricant metering system 10 will continue to add neat lubricant and water based on the can count in the Auto mode so long as the lubricant metering system 10 continues to operate in its normal operating conditions and the lubricant metering system 10 is not overridden by the operator To operate in the Auto mode based on can count, the controller 40 must have its power "ON", the Auto mode selected by mode selection switch 66, and the system operating in the normal range. If the level of emulsion in the reservoir 22 is either high or low, the Auto mode of controller 40 will be automatically interrupted by controller 40 to correct the amount of emulsion in the reservoir 22 Moreover, the Auto mode may also be interrupted by controller 40 if the level of neat lubricant in the neat lubricant supply 18 is detected as being extremely low. In either case, the can count will no longer be the basis for adding neat lubricant and/or water to circulation system 14. In the event that the level of emulsion in the reservoir 22 hits a high level, controller 40 will continue to obtain a can count as usual However, the addition of water will be prevented and the addition of neat lubricant will no longer be based on the can count. At this time, the addition of neat lubricant will be controlled by timers 82-84. The ON timer 82 is preset for approximately 10 seconds and the OFF timer 83 is preset for approximately 170 seconds More specifically, ON timer 82 activates lube injection pump 52 for a predetermined amount of time (approximately 10 seconds) at spaced apart intervals, while OFF timer 83 controls the amount of time (approximately 170 seconds) between ON timers 82 activating lube injection pump 52 for a predetermined amount of time. Thus, ON timer 82 and OFF timer 83 continuously cycles until the reservoir 22 returns to the normal level. When level control regulator 44 detects the level of emulsion in the reservoir 22 has reached the normal range or reset level, the addition of neat lubricant will continue for 30 seconds via lube delay timer 84 regardless of the can count. After the 30 second interval, the addition of neat lubricant and water will again be based on the can count as discussed above. This operation supplies the system with a minimum required amount of neat lubricant, even though the volume is high If the level of emulsion in the reservoir 22 is detected as being low by emulsion level regulator 44, then the can count will continue to be calculated by controller 40 as usual, however, the can count will no longer be the basis for the addition of neat lubricant and water to circulation system 14. Instead, the addition of neat lubricant and water will be controlled by five timers 85-89 of controller 40. More specifically, ON timer 85 activates lube injection pump 52 for a predetermined amount of time at spaced apart intervals, while OFF timer 86 controls the amount of time between ON timers 85 activating lube injection pump 52 for a predetermined amount of time. Thus, ON timer 85 and OFF timer 86 continuously cycles until the reservoir 22 reaches the normal level. Likewise, ON timer 87 opens solenoid valve 48 for a predetermined amount of time at spaced apart intervals, while OFF timer 88 controls the amount of time between ON timer 85 opening solenoid valve 48 for a predetermined amount of time. Solenoid valve 48 is continuously opened and closed via timers 87 and 88 until reservoir 22 reaches the normal level. The time periods for timers 85-88 are controlled by feed rate switch 68 so that the ratio of neat lubricant to water is maintained at the same ratio when the system 10 is operating under normal conditions. Of course, the time periods for timers 85-88 should be set at a rate which is faster than the consumption rate of the emulsion by equipment 12 such that the emulsion level in reservoir 22 is restored back to the normal range. Once the level of reservoir 22 has reached its normal level or range, delay ON timer 89 will continue to add neat lubricant and water to circulation system 14 for a predetermined period of time such as for approximately thirty seconds. In particular, the timers 85-89 will add neat lubricant and water to the circulation system

14 for a preset period of time, and then will turn off for a preset period of time to allow the system to determine if enough water and neat lubricant and water has been added to bring the reservoir 22 back to its normal operating range. If the reservoir 22 is still not in the normal operating range, the ON timers 85 and 87 will again add neat lubricant and water for a predetermined interval and then OFF timers 86 and 88 will control the amount of time before the ON timers 85 and 87 start adding neat lubricant and water. The OFF timers 86 and 88 provide level control regulator 44 time to determine if reservoir 22 is in the normal operating range. This process of adding neat lubricant and water via timers 85-89 will continue until level control regulator 44 determines that the reservoir 22 is back in the normal operating range. Of course, it will be apparent to those skilled in the art that the neat lubricant and water can continue to be added until it reaches a predetermined level within the reservoir 22. Preferably, this predetermined level is in the middle of the normal operating range.

In order to keep the exact ratio of neat lubricant to water, the ON timers 85 and 87 should be controlled according to the settings of the feed rate switch 68. For example, if the feed rate switch 68 is set for the fifth position, the ON timers 85 and 87 will each add neat lubricant and water for approximately 120 seconds and then OFF timers 86 and 88 will stop adding neat lubricant and water for approximately five seconds to allow level control regulator 44 to determine whether the reservoir 22 has reached the predetermined reset level The timers 85-88 continue to add neat lubricant and water until level regulator 44 sends a signal to controller 40 to stop adding neat lubricant and water via timers 85-88

When the sump level hits the normal range or the predetermined reset position, the addition of neat lubricant and water will continue via delay timer 86 for an additional thirty seconds regardless of the can count After the thirty seconds of additional neat lubricant and water, the controller 40 will switch back to the Auto mode such that the can count again will be the basis for the addition of water and neat lubricant to lube circulating system 14 Thus, neat lubricant and water will now be controlled by timers 80 and 81 as discussed above

Since feed rate switch 68 has ten selector positions, timers 80 and 81 must be set to run for different periods of time depending upon the setting of feed rate switch 68. For example, when the feed rate switch 68 is set to the first selector position, the lube ON timer 80 will be preset for approximately 40 seconds and the water ON timer 81 will be preset for approximately

120 seconds to obtain approximately a 1.0% neat lubricant to water ratio. When the feed rate switch 68 is set to the second selector position, the lube ON timer 80 is preset at approximately 60 seconds and the water ON timer 81 is preset at approximately 122 seconds to obtain approximately a 1 5% neat lubricant to water ratio. When the feed rate switch 68 is set to the third selector position, the lube ON timer 80 is preset for approximately 80 seconds and the water ON timer 81 is preset at approximately 121 seconds to obtain approximately a 2 0% neat lubricant to water ratio When the feed rate switch 68 is set to the fourth selector position, the lube ON timer 80 is preset at approximately 100 seconds and the water ON timer 81 is preset at approximately 121 seconds to obtain approximately a 2.5% neat lubricant to water ratio When the feed rate switch 68 is set to the fifth selector position, the lube ON timer 80 is preset at approximately 120 seconds and the water ON timer 81 is preset at approximately 120 seconds to obtain approximately a 3% neat lubricant to water ratio When the feed rate switch 68 is set to the sixth position, the lube ON timer 80 is preset at approximately 140 seconds and the water ON timer 81 is preset at approximately 119 seconds to obtain approximately 3.5% neat lubricant to water ratio When the feed rate switch 68 is set to the seventh selector position, the lube ON timer 80 is preset at approximately 160 seconds and the water ON timer 81 is preset at approximately 119 seconds to obtain approximately a 4.0% neat lubricant to water ratio. When the feed rate switch 68 is set to the eighth selector position, te lube ON timer 80 is preset at approximately 180 seconds and the water ON timer 81 is preset at approximately 118 seconds to obtain approximately a 4.5% neat lubricant to water ratio. When the feed rate switch 68 is set to the ninth selector position, the lube ON timer 80 is preset at approximately 200 seconds and the water ON timer 81 is preset at approximately 118 seconds to obtain approximately a 5.0% neat lubricant to water ratio. When the feed rate switch 68 is set to the tenth selector position, the lube ON timer 80 is preset at approximately 220 seconds and the water ON timer 81 is preset at approximately 117 seconds to obtain approximately 5.5% neat lubricant to water ratio. Of course, it will be apparent to those skilled in the art that the amount of time in which the neat lubricant and water are supplied to obtain the various ratios will change depending upon the particular flow rates of the water from water supply 16 as controlled by valve settings and of the neat lubricant from neat lubricant supply 18 as controlled by pump settings. In the Timed mode position, an ON timer 90 and an OFF timer 92 are used to regulate the addition of neat lubricant from neat lubricant supply 18 as set by the operator, while the water is manually added to reservoir 22 by the operator As mentioned above, the Timed mode bypasses controller 40. Thus, the Timed mode can be used if controller 40 malfunctions. Moreover, the Timed mode can be used to initially start up system 10 or to correct the ratio of neat lubricant to water in circulation system 14 In this mode, timers 90 and 92 activates lube injection pump 52 to add neat lubricant for a set period of time and then stop adding neat lubricant for a set period of time. This allows the operator to determine the amount of neat lubricant to be added to circulation system 14. The operator can set the timers 90 and 92 via timer buttons 70 for controlling the amount of neat lubricant being added to the circulation system 14 Preferably, each of the timers 90 and 92 can be independently set with four digit push buttons 70. Each push button 70 provides a different amount of time. For example, the first push button for each timer adds 100.0 seconds, the second push button for each timer adds 10.0 seconds, the third push button for each timer adds 1.0 second, and the fourth push button for each timer adds 0.1 second. Preferably, controller 40 will have various alarms for indicating when neat lubricant metering system 10 is no longer operating under normal operating conditions. These alarms can be lights on the control panel 38 of the controller 40 and/or audible alarms. The alarms should go on when one or more of the following additions occur (1 ) the level in the reservoir is detected as being high; (2) the level of the reservoir is detected as being low; (3) the level of neat lubricant in the neat lubricant supply is low; (4) the level of neat lubricant in the neat lubricant supply is extremely low, (5) when the sump level master air is off, (6) and/or (7) the air is off on the neat lubricant drum master. In the event that the neat lubπcant level hits extremely low, the addition of neat lubricant and water will be terminated until the neat lubricant level is back to at least the low level condition. However, as long as the program is in the Auto mode, the can count will continue.

Level control regulators 44 and 46 are both operatively coupled to controller 40 for providing information on the emulsion level in reservoir 22 and the neat lubricant level in neat lubricant supply 18, respectively. A variety of level regulators 44 and 46 could be utilized for level control regulators 44 and 46. Thus, level regulators 44 and 46 will not be discussed or illustrated in detail herein Henkel Surface Technologies manufactures a Level Control Two Point

Master/80225693 which could be utilized for level regulators 44 and 46. Of course, from this disclosure it will be apparent to those skilled in the art that other types of suitable level control assemblies could be utilized.

As diagrammatically illustrated in Fig. 1 , level regulator 44 has a sensor 94 located in reservoir 22 for measuring the emulsion level in reservoir 22 Sensor 94 should be capable of at least detecting a high emulsion level and a low emulsion level to define the normal operating range for the emulsion in reservoir 22. Of course, the sensor 94 of level regulator 44 is preferably capable of sensing the level of emulsion within reservoir 22 at various points such that the high and low level points can be adjusted. Moreover, level regulator 44 can be provided with an audible or visible alarm for indicating either a high level or a low level

Likewise, as seen in Fig. 1 , level regulator 46 includes a sensor 96 located in neat lubricant supply 18 for measuring the level of neat lubricant therein. The sensor 96 of lube level regulator 46 should be capable of at least sensing when the neat lubricant hits a low level and preferably also senses when the neat lubricant hits an extremely low level. Of course, sensor 96 of lube level regulator 46 preferably provides information about the level of neat lubricant in neat lubricant supply 18. When the neat lubricant of neat lubricant supply 18 hits a low level, an alarm should be activated at either level regulator 44 or control panel 38 to signal the operator to add neat lubricant to neat lubricant supply 18. When the extreme low level is reached, level regulator 46 sends an electrical signal to controller 40 to shut down neat lubricant metering system 10. As mentioned above, the flow of water from water supply 16 to reservoir 22 is controlled by solenoid valve 48 and modulating valve 50. Preferably, the solenoid valve 48 is a ball valve assembly such as the ball valve assembly 60227695 which is manufactured by Henkel Surface Technologies. Of course, any suitable ON/OFF valve can be utilized which can be controlled by controller 40. Solenoid valve 48 is controlled by various timers of the controller 40, as mentioned above, for opening and closing a conduit extending from water supply 16 to reservoir 22.

When the Auto mode position selector switch 66 is selected to the fifth position, the water ON timer 81 will open the solenoid valve for 120 seconds to add water to reservoir 22. After the 120 second interval has passed, energy will be removed from solenoid valve 48 thereby causing valve 48 to close and terminate the flow of water to reservoir 22 until either the can count reaches a predetermined count (e.g., 20,000) or the reservoir 22 is low. When a low level is detected in reservoir 22 by level regulator 44, ON timer 87 and OFF timer 88 are used to control the opening and closing of the solenoid valve 48. In the event that the emulsion in reservoir 22 hits a high level, energy will be removed from solenoid valve 48 to terminate the flow of water to reservoir 22 until level regulator 44 detects that the level of reservoir 22 has returned to the normal range. When the level of emulsion in reservoir 22 is detected as being high, this means that water and/or some other fluid has been inadvertently added to reservoir 22 or that the intervals between adding water and neat lubricant to reservoir 22 are too short. Accordingly, when the alarm goes off for a high level of emulsion in reservoir 22, the operator should inspect the emulsion to determine the cause of the abnormally high level of emulsion in reservoir 22. For example, if equipment 12 in the plant is being washed down, the water from washing down the equipment may have drained into the reservoir 22 causing the reservoir to go to a high level. The alarm will alert the operator that something is wrong. The neat lubricant metering system 10 will allow the operator to correct this problem by adjusting the feed rate switch 68 and/or use a manual override or Timed mode to add additional neat lubricant to circulation system 14 Preferably, controller 40 is provided with a manual override or one-shot button 72 which will add neat lubricant for approximately 120 seconds. The operator can continue to press the one-shot button 72 to add additional neat lubricant until the neat lubricant to water ratio returns to the desired mixture If less than 120 seconds of neat lubricant is desired, the operator can stop the addition of neat lubricant by repressing the one-shot button 72 during the 120 second interval to stop the addition of neat lubricant to circulation system 14.

Modulating valve 50 controls the amount of water which is being added through the conduit to reservoir 22. In this manner, the program for controller 40 does not need to be changed in order to increase or decrease the amount of water which is supplied at preset intervals by turning solenoid valve 48 to the ON position. Rather, adjustment of the water flow rate can be easily controlled by changing register settings of controller 40 which controls the aperture opening of modulating valve 50. in other words, modulating valve 50 is operatively coupled to controller 40 for adjusting the flow rate. In the preferred embodiment, modulating valve 50 is preset at a 20% open position such that anytime the controller power is switched "off" and then "on" again, the modulating valve 50 will completely close then reopen to its 20% open position. Of course, this percentage might vary from one plant to another depending upon the size of piping and/or the flow rate of water. In any event, the preset open position can be adjusted by the controller 40. In particular, modulating vaive 50 requires 5 seconds at 110 volts to be fully closed and requires 5 seconds at 110 volts to be fully opened. The modulating valve 50 has a valve closing timer (not shown) and a valve opening timer (not shown). The valve closing timer is preset at 900 intervals with each interval being 0.01 seconds, i e., nine seconds to move the valve through the entire range. The valve opening timer is preset at 100 intervals with each interval being 0.01 seconds such that it takes one second to move the 100 intervals. This allows the aperture size of modulating valve 50 to range from 0 to 100% open.

Injection pump 52 with ejector 54 is designed to add neat lubricant to the lube circulation header 30 of lube circulation 14 as determined by controller 40 In other words, injection pump

52 and ejector 54 are operatively coupled to controller 40 for adding neat lubricant to circulation system 14. Injection pump 52 can be, for example, a PA10F pump/60241006 or equivalent as supplied by Henkel Surface Technologies, while ejector 54 can be an injection valve/60225389 which is also supplied by Henkel Surface Technologies. Of course, it will be apparent to those skilled in the art from this disclosure that other types of injection pumps and ejectors can be utilized as needed and/or desired. The amount of neat lubricant being added during any time period or interval can be adjusted by adjusting the stroke length and/or pulse rate of the injector pump 52. Thus, fine adjustment of the amount of neat lubricant can be made by adjusting injection pump 52 rather than changing the program for controller 40. A check valve 53 is installed in the line between header 30 and lube injection pump 52 to prevent the emulsion from flowing back into pump 52

Operation of neat lubricant metering system 10 will now be described. Controller 40 includes a microprocessor that is programmed for providing neat lubricant and water to circulation system 14 by periodically adding water and neat lubπcant based on the output of equipment 12, e.g., can count, during normal operating conditions. All preset values of neat lubricant metering system 10 are accessible through registers or addresses of the PLC program In the preferred embodiment, controller 40 accommodates integers only, i.e., there is no floating point. The steps for initializing neat lubricant metering system 10 are as follows:

(1) Determine the desired default operating ratio of neat lubricant to water to be utilized in the particular application of neat lubricant metering system 10.

(2) Load default operating ratio into the program of controller 40. The fifth position of feed rate switch 68 which determines the lube concentration (percentage) is preferably preset at 3%. This is accomplished by entering 30 into the program of controller 40, i.e., concentration percent multiplied by ten. Also, the lube concentration increment must be set. Preferably, the preset lube concentration increment is preset at 0.5%. This can be entered into the program of the controller 40 by entering the value 5 into the program of controller 40, i.e., increment percentage multiplied by 10 The PLC will calculate the lube concentration for the rest of the positions of feed rate switch 68 from the base line or default setting of position 5. For example, the PLC will calculate the lube concentration of the feed rate switch 68 as follows 1 st position 3.0 - (4 x 0.5) = 1.0% Lube Concentration.

2nd position 3.0 - (3 x 0.5) = 1 5% Lube Concentration.

3rd position 3.0 - (2 x 0.5) = 2 0% Lube concentration 4th position 3.0 - (1 x 0.5) = 2.5% Lube Concentration 5th position 3.0 - (0 x 0.5) - 3.0% Lube Concentration

6th position 3.0 + (1 x0.5) = 3.5 % Lube Concentration.

7th position 3.0 + (2 x 0.5) = 4.0% Lube Concentration. 8th position 3.0 + (3 x 0.5) = 4.5% Lube Concentration.

9th position 3.0 + (4 x 0.5) = 5.0 % Lube Concentration.

10th position 3.0 + (5 x 0.5) = 5.0% Lube Concentration.

(3) Measure the water flow rate with the aperture of modulating valve 50 set at 20% open. If the flow rate is not 2.8 gallons per minute (GPM), then change the value of the water flow rate in the program of the controller 40 to change the size of the aperture opening of modulating valve 50. When entering the water flow rate into the program of controller 40, 2.8 GPM is entered as 28, i.e., GPM is multiplied by 10 with a minimum flow rate value of 20 and maximum flow rate value of 40.

(4) Set lube injection pump 52 to 50% stroke, and then enter the flow rate for the injection pump 52 into the program of controller 40. In the example illustrated and described herein, the flow rate of neat lubricant injection pump 52 is set at approximately 5 gallons per hour (GPH) when the neat lubricant injection pump 52 is set at 50% stroke. The neat lubricant flow rate is adjustable from 4 gallons per hour (GPH) minimum to 10 gallons per hour (GPH) maximum. (5) Set the high level point of level control regulator 44 for the emulsion in reservoir

22.

(6) Set the low level point of level control regulator 44 for the emulsion in reservoir 22.

(7) Set the low level of level control regulator 46 for the neat lubricant in neat lubricant supply 18.

(8) Set the extreme low level of level control regulator 46 for the neat lubricant in the neat lubricant supply 18.

(9) Set the output or can count in the program of the controller 40 for starting the Auto mode cycle. Preferably, the program of controller 40 is preset at 100 cans per pulse. An alternative design of the present invention can use an eductor instead of an injection pump to feed the lubricant directly to the sump. In this case, a solenoid valve will be added on the water supply line to the eductor which will be opened and closed in proportion to the can count production signal. Care must be taken with this type of system to ensure that the water supply pressure is constant and that check valves are used correctly to prevent backflow into the neat lube. The level control system will function in the same manner as described above, although the volume of additional water required will be much less, in the eductor alternative, the pressure in the water line will create a suction which will draw the neat lubricant from the neat lubricant supply when the solenoid valve is opened Accordingly, this will do away with the need of an injection pump A modulating valve could be utilized to make fine adjustments to the amount of neat lubricant being added to the water

A schematic view of the sensor system and controls of the present invention for a Dl aluminum can manufacturing line are illustrated in figure 6. In the figure, sensors 160 detect the production rate at the exit of one or more of cupper 161 , redrawing and ironing units 162 and 163, bodymaking section 164, trimming unit 165, necking unit 166, and flanging unit 167. The production rate information is fed into a flow controller 168 for calculation and comparison against present values. When sufficient production has occurred, flow controller 168 generates one or more signals 169 to flow controllers 173 (e.g., pumps, valves, needle valves etc ) for neat lubricant 170, water 171 , and any additives 172 that commence flow of one or more of these materials.

Typically, the flow controller will include needle valves and/or adjustable rate pumps that will generate flow of their respective components at rates corresponding to the desired proportions of each in the final lubricating mixture, preferably an oil-in-water emulsion known in the trade as a "coolant emulsion". The properly formulated lubricating mixture is then supplied to the punch and/or die tools of one or more of cupper unit 161 , redrawing unit 162, ironing unit 163, trimming unit 165, necking unit 166, and/or flanging unit 167 in suitable amounts. Although not shown in Fig. 6, excess coolant emulsion is then collected and returned for reuse.

While two embodiments have been chosen to describe and illustrate the present invention, it will be understood by those skilled in the art that various changes and modifications can be made without departing from the scope as defined in the appended claims Notably, the preceding description of the invention has been directed primarily to the manufacture of aluminum cans, as this application represents the largest volume area of application of the present invention. However, those skilled in the art will understand that, with some modifications, the invention applies to other processes in which equipment requires a continuous supply of a coolant emulsion.

Claims

The invention claimed is

1 A lubricant metering system for supplying a coolant emulsion to equipment, said lubricant metering system comprising a. a circulation system including a fluid reservoir; b. a water supply source that can selectively supply water to said reservoir; c. a neat lubricant supply source that can selectively supply a quantity of neat lubricant to said reservoir; d. at least one sensor that detects product output from equipment to be lubricated and generates at least one production signal for said product output; and e. a controller that detects said at least one production signal and controls supply of water and neat lubricant to said reservoir in response to said at least one production signal.

2. A lubricant metering system according to claim 1 , wherein said controller includes a circulation system level sensor that determines fluid level in said circulation system.

3. A lubricant metering system according to claim 1 , wherein said at least one production sensor detects a number of produced units at said output.

4 A lubricant metering system according to claim 1 , wherein said at least one production sensor detects a rate of production at said output.

5. A lubricant metering system according to claim 1 , wherein said equipment includes at least one punch used to make aluminum cans.

6. A lubricant metering system according to claim 1 , wherein said equipment includes at least one die used to make aluminum cans.

7. A lubricant metering system according to claim 1 , wherein said equipment includes at least one unit used to make aluminum cans, said unit being selected from the group consisting of a cupper unit, a redraw unit, an ironing unit, a trim unit, a neck unit, and a flange unit.

8. A lubricant metering system according to claim 7, wherein said controller includes settings that will maintain a selected ratio of neat lubricant to water within said reservoir based on the sensed production of aluminum cans.

9. A lubricant metering system according to claim 8, wherein said controller allows neat lubricant and water to be supplied to said reservoir based on a number of produced aluminum cans.

10. A lubricant metering system according to claim 8, wherein said controller allows neat lubricant and water to be supplied to said reservoir based on a rate of produced aluminum cans.

11. A method for controlling the supply of lubricant to equipment with a lubricant circulation system that comprises: a fluid reservoir that holds a lubricating mixture; a water supply source that can selectively supply water to said reservoir; a neat lubricant supply source that can selectively supply a quantity of neat lubricant to said reservoir; at least one production sensor that detects product output from equipment to be lubricated and generates at least one production signal for said product output; and a controller that detects said at least one production signal and controls supply of water and neat lubricant to said reservoir in response to said at least one production signal, said method including the steps of: a. sensing product output from said equipment and generating a product output signal; b. detecting said product output signal; and c. supplying said lubricating mixture from said reservoir to said equipment in re- sponse to said product output signal

12. A method according to claim 12, wherein said lubricating mixture is an oil-in-water emulsion

13. A method according to claim 12, wherein said lubricating mixture is supplied to said equipment based on a number of product units produced by said equipment.

14. A method according to claim 11 , wherein said lubricating mixture is supplied to said equipment based on a rate of product units produced by said equipment.

15. A method according to claim 11 , wherein said equipment is used to make aluminum cans, and said lubricating mixture is supplied to at least one unit selected from the group consisting of a cupper unit, a redraw unit, an ironing unit, a trimming unit, a necking unit, and a flanging unit, said lubricating mixture being supplied in an amount based on the production of aluminum cans by said at least one unit.

16. A method according to claim 5, wherein said lubricating mixture is supplied to a die, a punch, or both a die and a punch that are part of said at least one unit.