Infrared Application of the Month #1:
Heating Polyamide Pipe
A vehicle manufacturer uses various diameters of Polyamide pipe for the vehicles' pneumatic systems. The pipes arrive at the factory in large coils, awaiting process. Prior to use, the pipes must be uncoiled and "relaxed" then cut to length. Previously the relaxing had been done by means of a bank of ceramic heaters, with long heat-up and cool-down times. Line speed was limited. Heraeus Noblelight provided the manufacturer with a carbon infrared system that more than doubled line speed. Lower power consumption and quick heat-up/cool-down are among the other benefits now enjoyed.
Click for more IR applications... [ Back to Top ]
Infrared Application of the Month #2:
Digital Printing on Demand
The manufacturer of digital inkjet printing equipment for business and industrial applications sought a means to speed the printing process, in hopes of facilitating truly in-demand printing. The current process used hot air to dry ink/toner onto paper, causing a bottleneck in process time. The company approached Heraeus Noblelight for a faster, more efficient drying method. Heraeus application engineers provided a system that uses Heraeus's proven carbon twin-tube heater. The lamp provided even drying across the paper surfaces, and did so in reduced time.
Click for more examples of IR for industry... [ Back to Top ]
Tech Center Spotlight:
Shortwave Twintube Heaters
Shortwave IR heaters from Heraeus are suitable for all applications in which the attainment of high temperatures in the shortest possible time is what counts. Their emission maximum is between 0.9 and 1.6 micron. Among their advantages are high radiation density in the most compact space, and low space requirements.
Read more about Shortwave Twintube 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: Workpiece Characteristics and Their Effects, Part 2
Effect of power intensity
The flexibility of the corridor type of oven to change the heating condition significantly by
altering power intensity can be used to good effect in several ways. For example, reduced
power intensity is more suitable for workpieces of mixed gauges. Different heat settings
along the length of an oven may suit the curing of certain solvent-based coatings. The heat
transfer falls with distance as an inverse linear law, that is heat flux is inversely proportional
to wall separation.
Effect of conductivity
No significant temperature differences can be expected to occur when heat at the level
experienced in an infrared corridor oven flows into the core of a heavy metal item or across
a section heated on one side only.
Effect of product rotation
For the general case the number of revolutions made by a workpiece or loaded jig while in
the oven is the important criterion rather than the speed of rotation. A value of
approximately 10 revolutions produces a very acceptable temperature uniformity which is
comparable with that to be expected in convection oven practice.
Heating time compared to conveyor speed and product thickness
The time required to cure powder coating is virtually proportional to thickness of the
workpiece. A variable speed conveyor provides a method of maintaining maximum
production over a range of metal gauges.
Velocity and temperature of air
The main advantage of introducing fan circulation into an infrared oven is not to increase
heat transfer but to ensure uniform air temperatures from hearth to roof. The natural
tendency for air to stratify into hot and cooler layers is therefore negated. Circulation of air
at or close to the required temperature also has the advantage of optimizing temperature
uniformity on the product. It can also be observed on the trace of the run that the
workpiece starts to heat before entering the oven, This is encouraged by having extended
entry and exit reflective vestibules or doors of a reflective material which can be adjusted
to enhance reflectivity, Even in the open state parallel to the track the doors form an
effective infrared vestibule. For narrow work such as thin sheets they may be almost closed
to enhance heating inside the oven.
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.
|
