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moldmakingtechnology.com 25 Image courtesy of Synventive Molding Solutions. "Electric hot runner actuation is proven to provide precise control at both gate-open and gate-close sequences, and molders are trending toward electric valve gates on many applications," he says. "At Fakuma 2017, many hot runner manufacturers showcased this technology." Robert Harvey, director of Sales North America for HRS Flow (Byron Center, Michigan) says that servo-controlled valve gate systems provide far superior processing flexibil- ity than traditional valve-stem actuation. This is because of the ability to have precise control over the valve stem's speed and position during actuation and the ability to stop it in intermediate positions. Servo-controlled systems also provide for a larger processing window to accommodate competing requirements and conditions, such as the need to process out multiple cosmetic defects that are all dis- tinct from one another. Harvey says that positioning valve pin actuators (cylinders or servos) outboard from the drop and attaching them with a connecting rod provides flex- ibility in manifold pocket design for additional support and removes cylinders from the area of the hot manifold, which extends the life of the cylinder seals and reduces downtime. "We see the trend only increasing for full, servo valve-stem actuation because of the accuracy of pin actuation and the substantially increased processing window that can be achieved," he says, adding that the elimination of hydraulic lines and hydraulic seals results in reduced maintenance and increased uptime in all cases. "Servo valve-gate actua- tion also allows for storage of additional process variables, such as stem position and speed, across many cycles." Craig Reynolds, vice president of Business Development and Americas Service and Sales for Husky Injection Molding Systems Ltd. (Bolton, Ontario) says that the growing use of electric valve gate technology, which he believes will be mainstream soon, is giving molders more process control and repeatability. It also will result in operational cost savings since servo-driven systems use less energy than pneumatic or hydraulic valve gates. "It means that moldmakers will need to find a way to control the electric valve gates that will not require them to become computer programmers," he says. Making Hot Runner Systems Smarter Synventive's Bill Rousseau says that another industry trend involves the use of "smart tools" and the Internet of Things (IoT), and while the idea of completely autonomous pro- duction plants seems a long way off in the future, there are examples of companies taking those first steps today. "Control systems that now operate independently will start to be integrated, sharing information about the molding process and making appropriate adjustments," he says. "This melding of technologies that are currently separate will make them more powerful and easier to implement and operate." According to Robert Harvey of HRS Flow, program time- lines are being increasingly shortened, requiring very efficient transfer of design information and design execution along with faster manufacturing lead times. "Balancing the stringent quality requirements of more complex parts with operational needs like color changes is requiring more process flexibility from 'smarter' and more capable manifold systems," he says. "These systems are capable of controlling valve-stem speed and position and of providing process feedback." Providing Comprehensive Customer Service Brenda Clark, engineering manager for Hasco America Inc. (Fletcher, North Carolina), believes that one of the biggest challenges moldmakers and mold designers face is know- ing which hot runner system will support their applications and how to design, build and then maintain the chosen system over the life of the mold. She points out that the level of initial communication between the moldmaker, mold designer and the hot runner supplier is of the utmost Advances in pin-control technologies are making it possible to mold parts that were previously un-moldable. Shown here is an example in which a monitoring device remotely displays the position of the valve pin during the molding process, making it easier to confirm setup or perform troubleshooting. The system is also scalable, meaning the user can start out with simple pin-position sensing capabilities and, if warranted, upgrade to gain more levels of pin control.