Infrared heating assembly to heat a fast-moving web of specially coated filter membrane paper before the pleating process.
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 Medium Wave infrared heater for web heating |
 Control unit with safety circuits to prevent fires |
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scope of project
The client manufactures filters for the automotive industry and pleats paper-based material at high speed using a special system. To prevent the material from breaking, it needs to be pre-warmed before being pleated.
Specifications:
- Machine speed varies from 10 to 250 mtr./min.
- Temperature of material: 100°C +/- 5°C.
- Electrical parts must comply with all SA standards and regulations.
unitemp solution
An inrared heating system based on medium-wave emitter was chosen to inject sufficient energy at high speeds. The drawback is the potential fire hazard when a stoppage occurs and special precautions were taken in the design through forced cooling when the web comes to an abrupt standstill.
Temperature on the web is sensed via infrared pyrometers of the Raytek CI type. Via a Gefran 600 PID temperature controller and solid state switching the web temperature is controlled while the speed of the web is sensed. The faster the web moves, the more emitters are switched in as a baseload.
At the web exit a second pyrometer is installed to sense over temperature to prevent a fire.
The installation has proven extremely successful to the point that the client automated a second line with the same system and has not had a fire occurence in more than 3 years operation.