Strip heaters are used when there is a flat surface or the plate needs to be heated. Each configuration has several different options that can be added or changed depending on your needs. Negative heat transfer would be the case if the temperature value of an extruder zone is higher than the setpoint. In this case, the friction inside the barrel is so high that it actually needs to overheat and cool the barrel to maintain the selected temperature.
Tempco ceramic belt heaters have become extremely popular with OEMs as standard heaters for the drums of plastic injection molding machines, extruders and blow molding lines. A thin layer of the thermally conductive “high” MI material is used to electrically insulate the element wire from the inner diameter of the heater cover. A thicker, “lower” thermally conductive layer supports the elemental wire by directing the heat inwards to the part to be heated. The result is more efficient heat transfer, which lowers the temperatures of the element cable and increases the service life of the belt heating.
In general, heating absorbs electrical energy and converts it into heat. The temperature controller turns the heating on or off after comparing the preset target temperature with the actual process temperature supplied by the temperature sensor. However, temperature controllers cannot change the high current loads required by most heaters. For all but the smallest heaters, the system should include a load handling device such as a power regulator, SSR, SCR (silicon-controlled rectifier) or a mechanical relay. These electronic switchgear are able to process a large current and act according to the commands of the temperature controller. Standard Backer Hotwatt belt heaters are manufactured in one- or two-piece constructions with maximum inner diameters of 11 1/2″ or 22 1/2″.
Mica belt heaters are widely used in the plastic extrusion industry, but can also be used for other applications with maximum temperatures below 1000°F. MPI has a large stock of mica belt heaters Industrial Band Heater Manufacturer for same-day delivery. Customer-specific solutions are also available for fast delivery if required. Hi-Watt Inc. supplies heating systems and products for various industries throughout Michigan.
There are currently around 50 licensees operating 260 machines in 10 countries. When it’s time to replace or renew the tool, lightweight weighing designs should be ready to be implemented into the new tool. In the cycle time of 7 s, 1 g of reduced resin saves more than 500 g of resin per hour and cavity. At current prices, this saves about 0.85 $h and you can collect more than 8000 hours of just 1 year at $6800, which costs one tool per cavity. This means that the tool is already paid within the first year and benefits for another year.