
AUTOMATION
Part One of a Multi-Part Series Automation and Moldmaking: Mold Production in Action |
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LEARNMORE Process Management Leads to Easier Automation GETMOREINFO
For more information visit the MMT Showroom for Alpha Workholding Solutions. For more information visit the MMT Showroom for Charmilles. For more information visit the MMT Showroom for D-M-E. For more information visit the MMT Showroom for Makino. For more information visit the MMT Showroom for Mastercam/CNC Software, Inc. For more information visit the MMT Showroom for Mikron. For more information visit the MMT Showroom for System 3R USA Inc. For more information visit the MMT Showroom for Teksoft, Inc. While automation has been around for some time now, it has recently been gaining prominence in the moldmaking industry as moldmakers continually strive to cut costs and shorten leadtimes while maintaining quality and accuracy in their never-ending quest to compete both domestically and internationally. Incorporating automation in all aspects of the mold design and build process will increase equipment utilization and streamline operations, but automating operations is no easy task—mold designers and manufacturers need to change they way they think about their processes and consider how each part of the design and build process can benefit through automation (see Examining the Process Sidebar).
Automated electrode change on a Makino sinker EDM. Photos courtesy of Makino. Several leading manufacturers of machining equipment, EDM machines, software and components share their thoughts and experiences on the latest advancements in automation and what they mean to the shop in terms of the mold designer, engineer, moldmaker and mold assembler, as well as the process as a whole. They also discuss the challenges the industry faces in terms of automation and some recommended solutions to these challenges. EDM/Machining According to Vice President of Sales Mal Sudhakar at Mikron U.S. (Lincolnshire, IL)—a provider of high-speed and high-performance machining centers—the key to success among leading mold shops in the U.S. has been the investment in modern high-speed machining and EDM technologies and in automation. “In the face of intense international competition to drive labor costs down and with the relentless pressure from the markets to reduce leadtimes, moldmakers have been increasingly automating their high speed machining and EDM processes,” he notes. “This trend will keep growing rapidly in the coming years. With 8,760 hours available in a year, a mold shop that runs a single shift is down to 2,000 hours. The actual machining times may be only 50 or 60 percent of the 2,000 hours—depending on the time spent in setups and job preparation. With automation, there is tremendous untapped potential to increase the productive capacity of HSM and EDM machines and to reduce labor costs and leadtimes. Further, this opens up the potential for a mold shop to process multiple jobs on the equipment—to further reduce leadtimes.”
3R’s WorkMaster robot loads a palletized Alpha Workholding milling magnet in a Roku-Roku cell at F & S Tool (Erie, PA). Photo courtesy of Jim Dinger, F & S Tool and Alpha Workholding Solutions. The pressures of both domestic and global competition have led manufacturers to change the way they think and the way they work, asserts Henrik Sedvallson, CEO of System 3R USA Inc. (Totowa, NJ)—a supplier of manufacturing productivity tools. “Working smarter means obtaining greater manufacturing efficiencies and increased productivity,” he notes. William Howard, a product line manager for Makino (Mason, OH)—a manufacturer of horizontal machining centers, vertical machining centers, wire EDM and ram EDM machines, and graphite machining centers—expands on these thoughts, adding that successfully employing automation on the shop floor is all about increasing equipment utilization to reduce—or even eliminate—the costs and time associated with “non-value-added time” in the manufacturing process. “Higher equipment utilization will actually reduce manufacturing costs by producing more parts in less time on the same machine,” Howard states. “In addition , by producing more—in the same timeframe—leadtimes will be reduced, which also impacts carrying costs associated with all elements of the moldmaking process (i.e. purchased components, equipment costs, raw material, etc.). Like Charmilles’ Ledvon, Howard sees the industry streamlining the manufacturing process by consolidating multiple processes and operations onto a single machine, thereby reducing manufacturing complexity and the number of process steps, which helps improve part quality and precision, collapses the manufacturing time and makes the mold builder more responsive to the market. “Automation, in one form or another, facilitates all of the above advancements in the quest for global competitiveness in the moldmaking market.” The following are specific advancements which impact automation, Howard points out:
Brad Evans, national sales manager of Alpha Workholding Solutions (Hartland, WI)—a manufacturer of permanent electromagnetic workholding and material handling products—also sees an increase in the use of robotic load and unload cells. “The additions of these cells will increase the productivity of the moldmaker while reducing the overall operational costs and reducing leadtimes,” he states. Ledvon of Charmilles describes how these automated cells can impact the mold design and build process. “Looking at the work flow, graphite blocks are mounted on electrode holders (like System 3R Macro) and workpieces are mounted on pallets. Both are loaded in the robot magazine, and now the cell control software instructs the robot to load the electrode blanks into the milling machine The milling machine finishes the electrode and the robot loads it back into the electrode magazine. When some of the electrodes are finished the robot will load the electrode and workpiece blank into the diesinking machine, which will then complete the entire mold cavity including polishing. The next day or morning, the entire mold is made without human intervention. This is mold production in action.”
CamWorks performs automatic feature recognition and automated machining operations on the two-axis features of a mold. Image courtesy of Teksoft, Inc. “Automation is the bridge between EDM and precision production,” adds System 3R’s Sedvallson. “The companies that cross that bridge are those that are sure to be successful.” Mikron’s Sudhakar predicts an increasing availability of HSM and EDM machines with automation capabilities, more smart machining capabilities on machines to allow reliable unmanned operations, the integration of multiple processes such as HSM and EDM for the flow of both material and information, and the increasing use of a workshop management system to manage the complex flow of orders through the shop. Challenges/Solutions Expanding on Howard’s thoughts is Alpha Workholding Solutions’ Evans. “One of the greatest challenges facing moldmakers is the separation between the mold shops committed to process improvements and the ones not upgrading,” he comments. “If moldmakers do not automate, they will find it difficult to compete.”
Yet, Sudhakar of Mikron points out that some moldmaking equipment cannot be automated easily. “For example, a high-speed machining center may not be easily accessible for loading with a robot or even if it can be loaded, it hinders the normal accessibility to the machine for the operator,” he states. “The control also may not interface easily with a robot and even after all the issues are sorted out, the investment level may be quite high, which discourages the mold shop owner from investing in automation in the first place. “However, when considering a new machine, the moldmaker should thoroughly evaluate the automation capabilities of a machine and the availability of low-cost automation solutions that exist in the market,” Sudhakar emphasizes. Therefore, how to begin automating the shop can seem an insurmountable stumbling block for many moldmakers. “For those that recognize and understand the potential impact that automation could have on their business, the next question becomes ‘How do I get started?’” Howard notes. “The first step could be something as simple as adding automated load/unload capability to an existing machine—providing a quick, easy and productive method for increasing machine utilization and productivity by automating the flow of work in/out of the machine. Lightly attended or even unattended operations could an outgrowth of such a simple, initial step into automation.”
Mikron’s HSM 600(U) ProdMod high-speed machining center is designed for simultaneous five-axis machining of large workpieces in a truly high-speed mode, offers intelligent automation with pallet tables, and offers an interface for connecting with robotic devices—providing exceptional versatility. Photo courtesy of Mikron. Once these initial steps produce results and the benefits of automation are recognized and quantified, Howard notes that the question then becomes one of “rolling-out” automation (by introducing additional automation into manufacturing processes to realize an even greater impact) and “lean manufacturing” techniques (that consolidate process steps, shorten or consolidate the machining operations, improve quality and collapse manufacturing leadtimes, etc.) to more of the mold manufacturing shop floor. “Using automation to increase machine utilization and recognize lightly attended or unattended operations has been discussed as an initial step,” he says. “Grouping dependent machines/operations and using automation to automate the flow of work between the machines (i.e., a robot cell integrating a graphite mill and an EDM machine) is the next plateau in streamlining moldmaking operations, increasing productivity, reducing costs and cutting leadtimes.” Next, material handling automation, pallet changers, robots, etc. can be used to quickly and efficiently move raw material and tooling. “As equipment is more highly utilized, the response times of the support activities also will need to be addressed,” Howard states. “The traditional craftsmanship of the moldmaker must be captured in the pre-processing phase of the operations. CAD/CAM systems, tooling systems, part inspection techniques, etc. all must support a globally competitive mold building operation. Software for process management and planning must aid in getting parts quickly into and through the system—while DNC supports the download and distribution of data to the moldmaking shop floor.” Once automation is in place, Mikron’s Sudhakar notes that some moldmakers face the following issues: can the automation be “trusted” to run reliably in unmanned operation and how can the flow of work be managed through the various processes. To address these issues, he notes that there are a number of “smart machining modules” available on high speed machining centers, which brings intelligence to the high speed machining process in order to improve process reliability, optimize machining performance and allow reliable unmanned operation. These modules include an advanced process system, intelligent thermal control, operator support system and remote notification system (see MoldMaking Technology, March 2006). Beyond technology and equipment, Dave Lange, Director of Sales for the Americas for D-M-E (Madison Heights, MI)—a provider of mold bases and components, hot runner systems, mold controls and die cast tooling technology—advises moldmakers to scrutinize their processes to rise to the automation challenge. “Mold manufacturing setup is usually the first process to investigate whether time can be saved,” he says. “Today’s setup programs, tooling and toolchangers that are available have helped to minimize the actual machining time. If the spindle is not running or the electrode is not burning, non-production time is adding up. “With the CNC equipment that is available today through high speed milling and EDM, the automation factor permits quicker setups with emphasis put on jigs and fixtures that can hold different sized parts accurately and be set up quickly,” Lange continues. “Fixture plates that could be set up ahead of time with the cavities or cores off the machine and then swapped out when the operations are completed with those already in the machine could cut hours—and could easily justify the price of the fixtures.” Automated machine cells can focus on cutting mold cavities. And, these cells will be increasingly capable of supporting hundreds of tool positions.”
Automated graphite milling machine and sinker EDM cell. Photo courtesy of Makino. Software “From a software manufacturer’s point of view, automation allows the end-user to take advantage of multiaxis machines and high speed toolpaths to machine hardened steel (or other hard materials), whereas prior to this, the parts would require more tooling and would add more processes to their operations (such as hardening after machining, more polishing of the part, and more operations to finish the model),” Mund continues. “With multiaxis machines, a single setup replaces multiple setups on conventional three-axis machines, and the bottom line is there is less labor required to produce the same mold. Multiaxis machining is a key to automation and this trend will continue in the future.”
A robot arm changing a workpiece on a Makino E33 graphite and hard milling machine. Photo courtesy of Makino. Over at Teksoft, Inc. (Scottsdale, AZ)—a provider of CAM products for CNC machining (milling, turning, wire EDM and Challenges/Solutions
Another automation software challenge moldmakers may run into is software that automates the shop but doesn’t allow the operator to override it when necessary. “Shops need control over every aspect of their software, if you choose to have that much control in it,” Mund comments. “While automation is a great thing, nothing replaces the experience of an actual moldmaker no matter how good that software is! A shop needs software they using to be “open” enough that they can go in and have complete control over it any aspect of it.” According to Teksoft’s Coleman, sometimes it is difficult for moldmakers to see that not all components of a mold require three-axis machining. “For example, components such as slides are prismatic in nature and can benefit from an advanced Automatic Feature Recognition (AFR) features, which analyzes the part geometry and defines the most common machineable features for milling.” Furthermore, knowledge-based machining technology can take over from that point. “The automation engine then instinctively generates and associates machining operations and parameters for each feature,” Coleman explains. “Thus, even in moldmaking, machining operation sequences can be predefined and automatically applied when machining similar components.” In addition, some software packages’ knowledge-based principles are fully customizable to optimally represent your current machining environment, Coleman says. An adaptable, self-populating, standard establishing database helps prevent the all too common scenario where a shop’s efficiencies and competitive advantages are dependent on an individual programmer’s proprietary knowledge and experience.
D-M-E’s contour roughing service executes contour roughing on molds so moldmakers have more time to focus on implementing automation. Photo courtesy of D-M-E. Hot Runners/Components Lange also notes that mold change and color change on the same product also may be required. “Three plate molding is being replaced with hot runner molding in order to decrease cycle time and reduce material waste,” he notes. “The processor also is doing more than just molding the part. The automated processes of pad printing, hot stamping, gluing, assembling and packaging are now a part of getting the business. The days of ‘clip and ship’ are gone. The functions of labor-intensive secondary operations are quickly being entirely automated. Processors cannot afford to compete domestically and globally if human hands have to touch the parts after they’ve been molded. Printing, inserting, two-color, multi-component, and multi-material functions must be done without manual interaction.”
This shop is using automated equipment to accomplish faster turnarounds with lower production costs—thus accelerating deliveries to its customers. Photo courtesy of D-M-E. In the mold control area of the process, cavity pressure control of the molding machine is becoming increasingly important. Lange notes that controllers are being developed that yield close loop control of the process—thus correcting for other variations such as percent regrind, varying mold cooling temperatures and aging presses in general. “A controller’s improved slaving function provides the capability to create an offset in power between the master and slaved zone, thus allowing for some compensation in power output to correct for variations in heater tightness, heater wattage, mold cooling variations and the like.” Challenges/Solutions Solutions to these challenges lie in turning to emerging mold technologies, or established technologies that have previously not been widely used. “Spin and spin stack molds are becoming more popular,” Lange notes. “Rotational molds and machine platens are more prevalent than ever. These technologies were once only for larger operations, but now even 15- to 20-man shops are making multi-component, core back, rotational molds. Automation in a moldmaking shop has to be adaptable to enable work with shorter runs of parts versus a fixed set of automated equipment. Automated machine cells can focus on cutting mold cavities.” The Long Haul |
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