23 Aug 2001
Process Control with Dynamic Feed from Synventive Molding Solutions
´s-Gravendeel, August 2001. – Synventive Molding Solutions launches Dynamic FeedTM, a unique and patented process control system. Dynamic FeedTM provides independent ‘real time’ process control of each gate. The degree of control is the same as having a separate injection unit at each gate. Each gate can have a different injection pressure, injection time, pack pressure and pack time. The injection and packing pressure profiles are independently controlled. Each nozzle of the hot runner is fitted with a flow control pin operated by a control valve, similar to standard valve gate assemblies. The variable position of the flow control pin will affect the flow rate to each cavity. Pressure is measured in each nozzle downstream of the flow control pin just prior to the melt entering each cavity. A PID controller is used to control the pin’s position based on the injection and packing profiles determined for each cavity.
With Dynamic FeedTM it is not necessary to profile the injection and packing pressure of the injection unit.
The injection unit is set at a constant pressure while the injection and packing profiles are controlled by the hot runner system and the Dynamic FeedTM Controller. This eliminates variation along the process and controls the melt closer to the cavity.
Dynamic FeedTM offers several advantages:
* improved productivity: independent process control to each gate allows a
wider processing window and faster start-ups with lower reject rates. Tools
can have increased cavities while still holding critical dimensions.
* reduced time to market: by providing more opportunity for family moulds and
modular tooling. The process control characteristics also allow for faster
tool qualification time.
* lower tooling cost: fewer moulds are required for family mould projects.
Tools can be manufactured with more cavities to meet production needs.
Cavity-to-cavity consistency can be greatly improved with Dynamic FeedTM system. In typical multi-cavity moulding conditions, part weights can differ and dimensions can be slightly different even when the cavities are machined identically. Most of these small dimensional changes can be modified by changing the packing time and pressures. The Dynamic FeedTM system allows each cavity to have its own unique packing pressure and time to reduce the variation from cavity to cavity.
Traditional moulding problems with family moulds or moulds with cavities of varying thickness are also eliminated by the individual control. Family moulds can now have an optimized process for each hot runner nozzle (or cavity). Dynamic FeedTM can mould 3, 5, or a non-balanced number of cavities.
A conventional hot runner system mechanically balances the mould by changing the bore and drop sizes.
Dynamic FeedTM balancing is performed by dynamically changing the position of the valve pin in the flow channel. Dynamic FeedTM gives full process control over each nozzle.
Other benefits of family moulding would include colour matching, reduced inventory, and a more efficient assembly process.
At the K-show (25 October – 1 November 2001, Düsseldorf, Germany)) Synventive will demontrate the advantages of Dynamic FeedTM live. Interested visitors are welcome to visit the Synventive Molding Solutions booth, number C10 in hall 1.
Reader enquiries
Synventive Molding Solutions BV
Griendweg 7b-9
‘s Gravendeel
Netherlands
Notes for editors
Over the past decades, Synventive Molding Solutions and its predecessors (Dynisco HotRunners, Eurotool, Kona) have served customers in the automotive, electronics, telecommunications, packaging, medical, consumer/industrial and PET industries. Today, with manufacturing, service and support operations employing more than 400 people in over 15 countries, the company’s mission is to enable the success of its customers through advanced injection molding technologies, best-of-class engineering and superior service.
Editorial enquiries
Bart Jan Jongenotter
Synventive Molding Solutions BV
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