Infrared heater manufacturer Research Inc., Eden Prairie, Minn., keeps track of its infrared heating installations to show prospective and existing customers how it solves application problems. One of the case histories Research Inc. posted describes a customer’s problem that reduced product quality – uneven heating.
The company, a maker of specialty polyester film, struggled to maintain temperature while faced with an insufficient heat source, line-speed limitations and space restrictions. More specifically, the manufacturer faced the following issues:
- The existing medium-density heaters were rated at 40 W/in2, which was insufficient for the process.
- A line speed of 130' was required, but the existing heat source only could accommodate line speeds of 100 ft/min.
- The 47" polyester film reached the required temperature in the center of the web, but it was several degrees cooler on the edges.
- Space was limited above and below the film line. The only available location for new heaters was a point on the web where the film travel was vertical.
The benefits were many, according to Research Inc. The customer now has a sufficient heat source with the infrared panel heaters providing 100 W/in2. The line speed meets the required 130 ft/min and has the capability to reach 160 ft/min. For even heating, the center and end heat zones compensate for heat loss at the edges of the polyester film. And finally, by installing the high density Pyropanels vertically on the line, the film manufacturer achieved the desired results in the space available.