Infrared Application of the Month #1:
Preheating of Cushion Flooring
A major manufacturer of cushion flooring required process heat for preheating prior to embossing of their flooring product. Their current system--installed in 2005--did not offer zone heating control.
A new system from Heraeus Noblelight provides the requred heat via carbon mediumave infrared heaters, and featured three-zone control; one of these zones is thyristor controlled through optical pyrometers and a control panel. Because the Heraus system's footprint is nearly identical to that of the previous heater, installation caused mimnimal disruption to production.
Click for more IR applications... [ Back to Top ]
Infrared Application of the Month #2:
Curing Powder Coating on Electric Motor Casings
A powder coating process for an electric motor casing with stator package had been using a solvent-based lacquer, with drying by ambient temperature. This system had a number of disadvantages: the use of solvents caused problems with regard to some environmental regulations; the powder coating process required a great deal of energy; and curing time was long.
A new infrared system from Heraeus Noblelight allows use of a non-solvent based lacquer, reduces heat-up time, maintains high throughput and reduces curing time by more than 90%. The systems features heating zones to accomodate various size casings.
Click for more IR applications... [ Back to Top ]
Tech Center Spotlight:
Mediumwave IR Heaters
Plastics, water and other solvents absorb medium wave radiation especially well. The use of medium wave infrared heaters helps in the effective drying of paints and lacquers and in the economical processing of plastic foils and sheet. Because of their long life, these heaters are best suited for continuous process. Surface films and very thin materials are heated up extremely efficiently.
Read more about Mediumwave IR Heaters... [ Back to Top ]
Special Designs:
Hybrid Carbon/Shortwave Heaters
Heraeus Noblelight's hybrid Carbon/Shortwave heater offers all of the benefits of Carbon and Shortwave heaters using Heraeus' proven twin-tube design. This infrared heater combines a carbon heater and a short wave infrared heater in the proven quartz glass twin tube.
For more on Hybrid Heaters, click HERE.
A wide assortment of other special design heaters is available from Heraeus. Click HERE for details.
[ Back to Top ]
Technical Learning: Introduction to IR Technology, Part 4 (conclusion)
Developments in process heating
During World War II infrared heating became more widely recognized. The main applications were in the metal finishing fields, notably in the curing and drying of paints and lacquers on military equipment. Banks of lamp bulbs were used very successfully, and although by today's standards the power intensities were very low, the technique offered much faster drying than the fuel-fired convection ovens of the time. Production bottlenecks were overcome and military supplies to the armed forces were maintained.
After the urgency of war production had passed, the adoption of infrared heating techniques continued, albeit on a much slower basis. As industries reverted to normal peace time operations, prewar methods of production were reinstated in order to resume full output as quickly as possible, and to provide immediate employment for the returning members of the armed forces.
However, in the mid 1950s the motor vehicle industry again began to show interest in the capabilities of infrared for paint curing, and a number of production line infrared tunnels came into use. The familiar lamp bulbs were by now being complemented by a new tubular lamp of higher radiant intensity but smaller in physical size. This allowed a much higher packing density to be achieved, hence a higher power intensity over a given area of radiant emission.
With the interest in infrared heating now renewed, new types of heat sources (heaters) were developed to fill the ever widening needs of industry. There now exists a variety of types, shapes and sizes with an extensive range of intensities and operating temperatures. This flexibility enables the equipment designer to meet a vast range of process heating requirements, such as paint curing, moisture evaporation, printing ink drying and heating of solid materials. Thus the technique is not restricted to a unique heating condition but may be as powerful or as gentle as a particular process requires.
Summary of benefits
The growth in popularity of infrared systems over the past 30 years stems not only from numerous production benefits provided by this form of heating but also from more mechanized production processes and new heat setting materials being deployed in industry. Certain benefits are, of course, common to all infrared systems, but additional specific benefits are often obtained depending on the process under consideration.
In general infrared systems provide the following:
- Rapid heating of the product. In all but a few exceptional cases radiative transfer of heat is much faster than convection. A more constant rate of heating is obtained because the source temperature is normally much higher than that of the product, even at the end of the heating cycle.
- Low energy costs because of short heating times, and the ability to apply the heat only where and when it is required.
- Cleanliness in operation as the heat sources do not cause contamination.
- Elimination of atmospheric pollution due to the absence of combustion products.
- Ease of control combined with safe operation.
View a variety of technical bulletins... [ Back to Top ]
That's it for this month's issue of Application Notes for IR Heating. Feel free to encourage your colleagues to subscribe. Just click HERE to send them an invitation to subscribe. It's quick, easy, FREE, and no-obligation.
|
