Lights-Out All-Electric Molding in Taiwan

An international concurrent process engineering project has resulted in the creation of what could very well be one of the most technologically advanced injection molding plants anywhere in the world. It is a highly automated, fully integrated manufacturing facility featuring a network of unmanned workcells with high-speed, all-electric injection molding machines. The factory is dedicated to the production of high-quality, thin-wall jewel boxes for CDs and other optical media formats at competitive prices for the world market.

Its production systems are agile enough to meet customer requirements, which may range from single- to multipack jewel boxes in any specified color, and it does so with minimal human intervention and the costly errors such intervention can cause. Even though it involves new technology used in new ways, innovative international cooperation brought this facility on-stream, from concept to production, in just nine months. Full production started in the summer of 1997. Today the plant produces 1.1 million jewel boxes every 24 hours. And it has inventory capacity for 4.5 million boxes.

The plant belongs to CMC Magnetics Corp. (Taipei, Taiwan). With average annual sales of $140 million and a net profit of around $50 million, CMC, a publicly traded company since 1994, also owns a manufacturing company called Europa Magnetics Corp. (EMC, Newcastle, UK), and Hotan Corp. (Dublin, CA), a U.S. sales office. Among its other accomplishments, CMC Magnetics is the largest producer of microfloppy diskettes in the world, owning a 19.05 percent share of the global market in fiscal 1997. It expects to command a 23.38 percent share of the global diskette market in this fiscal year. CMC also is a full-service CD-R replicator. By October of last year, CMC had 35 CD-R lines in operation with a monthly capacity of 7 million pieces. And late last year, CMC opened a brand-new manufacturing plant in Taiwan for production of advanced multimedia optical products, such as DVD and CD-RW.

Jewel boxes are produced at CMC's King Lin 2nd factory in Ping Chen City, Taiwan. The plant runs 24-7 in three shifts, but its 37 employees, involved mostly in inspection, assembly, and packaging, have no need to. Trays and lids are molded in PS from two domestic suppliers. CMC uses about 450 tons of PS a month. Resins are delivered on demand from two 60-ton silos into the plant's centralized, closed loop materials handling and color-blending system from Comet Automation.

Jewel boxes are molded in two different types of molding systems, supported by servorobots, fixed automation, and automated peripheral equipment. Six 260-metric-ton Sumitomo molding machines run eight-cavity tooling from Fuji Seiki, and 12 300-metric-ton Fanuc all-electric Roboshot Alphas run eight-cavity Mitsubishi molds. A twin-machine cell runs multipack jewel boxes. CMC bought the first 300-metric-ton Fanucs ever built. Johnson Chang, a 20-year molding veteran with 12 years of experience at CMC, is vice general manager at the King Lin 2nd factory. He says the Sumitomos will soon be replaced by Fanucs. "The 21st century will be all all-electric," Chang states with confidence.

Even with all the automation involved, the plant has no central computer control system. "If the central computer breaks, I would lose my whole factory," Chang explains. "The Fanuc machine controls provide the links to all the processing data and all the control systems for the automation, including the robots and the hot runners."

With its strong R&D team, its existing global marketing channels, continuing capital investment, and its experience in competitive low-cost/high-yield automation, CMC expects to grow its share of the global optical media jewel box market from 2.3 percent in fiscal 1997 to 5.3 percent in fiscal 1998, and to 8.3 percent by fiscal 2000. CMC expects to benefit from the capital and the production management expertise it has invested into this project. But other molders all over the world will benefit from the efforts it has invested in making its dream plant a reality.

A Way of the Future
What has been accomplished at CMC's jewel box factory is a prime example of a paradigm shift now taking place in the business, a change having to do with the practical application of high technology through world-class cooperation. This project brought together suppliers of some of the most advanced molding technologies on the planet, including Fanuc, American MSI Corp., and Yushin Precision Equipment. This shows what can be done when suppliers are brought in early and are engaged in frank and open discussions with a molder willing to buy the best available to achieve pure production capacity with the lowest possible overhead. Many of the latest molding systems from these suppliers that we have seen at recent trade expositions around the world were alpha- and beta-tested at CMC. All molders now can avail themselves of the breakthroughs that were originally brought about by the CMC project.

Like most customers of all-electric machines, CMC's Johnson Chang says servodriven machines can provide superior energy efficiency and cleanliness and reduced operating noise and maintenance costs when compared to their hydraulically driven counterparts. His CNC Fanuc machines also provide the accuracy and repeatability necessary for reliable unmanned molding. The Roboshot's a-c servodriven clamp and ejector motions perform at a setpoint repeatability to within ±.0005 inch shot after shot. Such accuracy helps maintain the dimensional stability of the thin-wall parts, and much more.

For example, during the cycle, to speed production cycles, the mold opens only about 2 to 3 inches--just enough room for the Yushin servorobot arm to get in. The robot also had to be designed for pinpoint accuracy and speed. The unusually shaped end-of-arm tools Yushin designed for CMC are lightweight for high-speed operation, but they are structurally sound.

Speed is key in molding thin jewel boxes, where 1 second can mean competitive life or death. Walls are nominally 1.1 to 1.5 mm thick. Fanuc engineers developed a system that provides high-speed injection. Special low-inertia motors for clamping systems and ejectors also were designed for CMC, and systems and programs to overlap key phases of the cycle were developed to reduce cycle times. As a result, running its eight-cavity tools, cycle times are 6.36 seconds on the Fanucs, shot after shot. CMC's hydraulic machines run its eight-cavity molds at 7 seconds. "We can go down to 5.5 seconds on the Fanucs if we wanted to, but we keep them at around 6 seconds for safety's sake," says Chang. "And we have no worries about servovalve maintenance with the electric machines." These high-speed systems are now standard on Fanuc molding machines worldwide.

American MSI officials say that its latest Delta series of hot runner controllers was just a concept when the CMC project came along. The project brought into play a factor American MSI had never even considered--installing its controllers directly onto the Fanuc machines, creating truly integrated hot runner control. CMC felt this approach would allow for fine tuning of its mold setups with the MSI controller and then, through the SPI Communications Protocol, automatically interfacing the mold settings into the Roboshot's control.

Eliminating a separate hot runner controller certainly saves on floor space as well, which was an important consideration in CMC's space-efficient plant layout. MSI began working closely together with Fanuc in the fall of 1996 and began shipping its first Delta controllers only four months later.

In January of 1998, American MSI and Milacron/Fanuc announced that fully integrated Delta series hot runner control, providing up to 48 zones of control, is now available on the complete line of Roboshots, from 17 to 330 tons, as a standard option. Everyone benefits.