FlowControl. Smart & Effective. Stabilize your Process

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1 FlowControl Smart & Effective Stabilize your Process

2 FlowControl Demanding visual appearance with precise dimensional stability Gloss level, evenly textured surfaces, color uniformity and aesthetics, are all determinants for the visual quality of modern plastic parts. In addition to these factors, today s parts also require optimum dimensional stability and perfect surfaces in the gating area. Molding quality parts is more challenging than ever, and common molding processes often are not sufficiently meeting these requirements. Complete control of the plastic flow is necessary to reduce or eliminate defects and ensure high quality, consistent molded parts. Filling details: Fill time_1 = [s] Flow front accelerations and stagnations can cause visible surface defects. Bumper-Seq Pressure at gates MPa The opening of the outer nozzles causes a localized spike in pressure as well as a corresponding pressure decline away from the gate. Typical error patterns: Nozzle group 3 open [s] Smart & Effective Nozzle group 4 open Sec. Stable processes through advanced flow control Until now, the filling process in multiple gated parts has only been controlled by the opening and closing of the valve gates. The molder can choose when the pins open and close but he has no control over the speed and stroke of the valve pins. This can make it difficult to achieve premium quality parts, especially when cascade molding with difficult cosmetic requirements. In cascade molding the filling of the part begins out of one or more gates while the other gates remain closed until the flow front passes them. This is done to eliminate weld lines but can cause other types of cosmetic defects. While the flow front is advancing in the part out of the originally opened gates, pressure is building inside the hot runner behind the gates that are still closed. When these gates finally do open the highly pressurized plastic inside the hot runner is released into the cavity causing a sudden acceleration of the flow front near the newly opened gate. This sudden release of pressure also causes a pressure decline at the originally opened gates, resulting in a temporary deceleration of the flow front in other areas of the part. These abrupt flow front velocity changes, and therefore the flow marks resulting from them, can be greatly reduced or eliminated by individually controlling the velocity and stroke of each valve pin. SynFlow, egate and Dynamic Feed are Synventive technologies which provide flow control to produce parts with perfect surface quality, dimensional stability and reproducibility. Flow marks Opposite gating marks Sink marks after coating

3 Dynamic Feed Ultimate Control Individual melt pressure control at each gate Dynamic Feed provides individual melt pressure control in each gating area. Every gate receives the precise injection and pack pressure profile that is predefined for their position, giving you the same level of control as having separate injection units located at each hot runner nozzle. In the injection and pack pressure stages, the filling of the cavity is individually adjusted and controlled by intelligent software. Differences in flow velocity, differential pressure in the cavity, or influences of deviating material viscosities during the filling are eliminated by Dynamic Feed. Additionally, sink marks and dimensional stability are greatly improved by the custom pack pressure profile. As a result, dimensional stable parts with the highest level of surface quality can be manufactured in a way that is both process stable and reproducible. Dynamic Feed assures the highest qualities with excellent surfaces, including tightest tolerances, dimensional stability and perfect reproducibility of complex molded parts. Dynamic Feed Actual Target Dynamic Feed For a wide variety of injection molding applications: in single cavity molds: for complex part geometries in multi cavity molds: for precision and consistency in higher cavitation molds in modular molds: for different cavities in the mold base and modular tool inserts in family molds: for different or complementary parts in one mold unit

4 SynFlow Optimized flow control Valve opening control for hydraulic valve gate systems in cascade molding SynFlow is a velocity and position-dependent opening stroke control system for hydraulic valve gated hot runner systems. It allows the user to define the opening velocity of the valve pin and the amount of the opening stroke over which the velocity will be controlled. With SynFlow you can define: the designated opening velocity the length of the opening stroke which the opening velocity is controlled (at the end of the defined opening stroke the velcity will raise back to maximum.) By regulating the flow of hydraulic fluid to the opening port of the valve gate piston, SynFlow is able to control how quickly the valve pin opens. Users gain a level of control that allows for a regulated release of melt pressure into the cavity SynFlow Opening with defined velocity profile mm 4mm 2mm SynFlow benefits: Valve pin closed Valve pin opened selective reduction of the valve pin opening velocity where it s most effective real-time valve-pin position monitoring reproducible velocity regulation precise control of the opening profile prevents molding defects such as: pressure alteration marks opposite direct gating marks sink marks reduced adhesion of finishes The user gets clean parts with perfect surface quality, reducing rejects and improving process efficiency. TIME Two examples of advanced surface qualities by using SynFlow

5 egate Surface quality & dimensional stability Electronically controlled valve gate system provides cleanliness, energy efficiency, precision and flow control egate is an electronically controlled valve gate system which provides significant advantages over conventional hydraulic and pneumatic actuation beyond the obvious cleanliness and energy efficiency. With response times of less than.1 seconds and precise position control to.1mm, egate offers unparalleled repeatability. Through its ability to adjust the valve pin s open position, close position, velocity and acceleration, egate provides advanced flow control for the most demanding cosmetic applications. Pin Position (mm) Nozzle 1 Cycle: 3316 Nozzle 2 Cycle: Cycle Time (sec) Cycle Time (sec) Velocity (mm/sec) Pin Position (mm) Velocity (mm/sec) egate egate benefits: Real-time process monitoring of pin position and velocity Response times of less than.1 sec Open and close position repeatability to.1 mm Ability to adjust and control the pin s open position, close position, velocity and acceleration No plumbing or gun-drilling of hydraulic or pneumatic lines Ideal for all-electric molding and clean room applications Differing valve pin velocities at each cycle egate offers cost-effective, high quality and process stable manufacturing to its users. With egate the best qualities for sensitive part surfaces can be obtained, resulting in excellent aesthetics. Examples of premium consumer and electronic products producible with egate systems

6 FlowControl Stabilize your Process KNOWLEDGE & CONSULTANCY LEADING TECHNOLOGIES STABILIZE YOUR PROCESS CUSTOM SOLUTIONS GLOBAL SERVICES In 26 countries worldwide North America Synventive Molding Solutions Inc. 1 Centennial Drive Peabody, MA 196, USA Tel.: Fax: info@synventive.com Europe Synventive Molding Solutions GmbH Heimrodstr Bensheim, Germany Tel.: +49 ()6251/9332- Fax: +49 () 6251/ infohrde@synventive.com Asia Synventive Molding Solutions (Suzhou) Co.Ltd. 12B Gang Tian Industrial Square Suzhou Industrial Park, China Tel.: Fax: infohrcn@synventive.com Stabilize your Process