Electric machines have significantly improved the vitality efficiency from the injection molding industry over the last 20 years. New strategies to save energy while keeping costs down during periods of rising energy costs is the need of the hour. Melt-stream heating, particularly from the barrel, presents a solid prospect. Typically, 30-70% of your power consumed by heater bands is wasted by radiation and convection to the surrounding environment. Eliminating these losses will reduce specific energy usage and allow machines being pre-heated faster using the same power delivery infrastructure, thereby reducing downtime to increase productivity. Inherent characteristics of band-heaters also hamper temperature control response, limiting improvements partly-to-part quality uniformity and efforts to lessen change-over times. A band heater’s temperature must first rise above that relating to the barrel before the barrel might be heated, and conversely, a band-heater’s temperature must fall below that of the barrel prior to it being cooled. The thermal mass of band-heaters along with the thermal contact resistance between them as well as the barrel, therefore significantly boost the thermal inertia in the melt stream. The recent introduction of lower weight radiant heating elements provides an opportunity for improvement. Another new technology that provides significant advantages is noncontact induction. Barrel heating using helical induction coils is considered for decades, but was poorly applied. Past efforts often used inefficient low-frequency power supplies and constantly placed the coils in direct experience of the barrel, undermining the compelling advantages of induction. Heat generated in the barrel was still allowed to escape to ambient and also the coils’ thermal mass wasn’t removed from the equation. Connection with the recent barrel also increased the coil’s electrical resistance & reduced efficiency gains.
Xaloy nXheat™ induction barrel heating (patent pending) sharply cuts energy costs and improves temperature control for higher quality and much less scrap compared to conventional heater bands. The nXheat ™ barrel heating solution (patent-pending) uses an optimized high-frequency power source along with a thermal insulating layer interposed between the barrel and coils to deal with the aforementioned issues and exploit the total potential of induction. Each of the heat is generated directly within the barrel and stays at the same time. The coil’s thermal mass can also be eliminated, and coil resistive losses are negligible hence the exterior surface is cool to the touch. Barrel heating efficiency approaches 100 % and temperature control response is quite a bit improved.
Energy savings for barrel heating of up to 70% in contrast to heater bands
• Additional energy savings – upto 35% more – on account of reduced air cooling load
• Additional energy cost reduction from reduced peak power demand
• Fewer heater failures to cut downtime and maintenance costs
• Immediate cooling and heating reply to improve quality and lower scrap
• Quicker heat-up, typically 2X or more, to increase productivity
• More heating capacity- typically 3X higher wattage in to the barrel- eliminates a bottleneck
• Higher barrel temperature power to mold high-temperature polymers, or metal
• Cool exposed surfaces for increased operator safety
The nXheat™ system relies on a high-frequency power source and helical induction coils to produce heat directly in the barrel wall. A thermal insulating layer is interposed involving the coils and barrel to combat heat loss, increase efficiency and improve control response.
The program can be found in two forms:
1) all-zone nXheat™ through which induction heating completely replaces conventional heater bands;
2) nXheat-Hybrid™ by which power-saving induction technology heats the barrel’s feed zone while conventional band heaters handle downstream zones.
All-zone nXheat™ delivers maximum savings in power consumption, about 50-70%. This is basically the ideal system for larger machines with over three heating zones due to the high price of the decline in power consumption.
On smaller machines with two or three zones the nXheat-Hybrid™ system can deliver the majority of the savings of the all-zone system because induction is used from the barrel’s feed zone where the greatest amount of heat input must start the melting process. On such machines, which generally have barrels with inside diameters of 50 mm or less, the hybrid system will typically give a 30 to 50% lowering of power consumption.
Inside the hybrid system, downstream zones dexmpky42 use either insulated or uninsulated band heaters. Greater energy savings are achieved with the aid of insulated band heaters. The same sheet insulation which is used in the induction-heated feed zone can be used to wrap the downstream band heaters. The precision and fast response of induction heating in the feed zone will also substantially reduce temperature overshoot things that may appear with insulated band heaters.
The program will cover itself with power financial savings as well as other cost and quality benefits. Some examples are reduced scrap stemming from less variation in melt temperature and faster reaction to variations in target melt temperature. The payback period on investment costs for such systems is highly influenced by electricity rates, machine size and production schedule (hours of operation each year). This kind of system typically costs about 25-50% of your all-zone system.