In the past, most extruders have used traditional convection ovens to heat their dies. In the older systems, the oven heats up all the air in the chamber. Then they must rely on the air to pass the heat onto the die. The disadvantage to this system is it requires more time and more energy.

On the other hand, an infra-red oven uses a band of waves to “excite” the metal particles in the die, much like your microwave oven at home functions. Early on this technology had some real challenges when attempting to use infra-red waves to heat steel. At the time, infra-red waves simply required far too much energy to make the process cost effective.

Novatec eliminated this problem by producing an infra-red die oven which singles out the wave-length that effects carbon steel. By using this system of generating a small band of infra-red waves, we use a lot less energy while still getting the benefit of infra-red heating without the cost.

Five methods to justify the Novatec die oven

1. Reduction in die breakage:  The Werner Extrusion Company (Greenville, PA) reports an almost 90% reduction in die breakage since installation of their die oven.  Werner reported a die breakage rate (average) of 23 dies per quarter.  Since installation of the Novatec oven, it is down to 3 per quarter.  Reasons for this are quite simple.  Where 99% of all dies broken are reported to happen with the first billet – improperly heated dies are the culprit.  Traditional convection die ovens not only under heat dies, they heat them very unevenly.  Under heated and unevenly heated dies make incredibly adverse forces during the first billet.  The reason we do not see many, if any broken dies after the first billet is the fact that after pushing a billet through a die, that die becomes evenly heated.
2. Reduction in “die pulls”:  Those customers who keep track of die pulls otherwise known as die failure report back that they see a great reduction of this.  Reports show as much as a 90% reduction in die pulls.  Example:  Futura Industries (Clearfield Utah) prior the installation of the Novatec oven averaged 20 per month.  After installation of the oven, this number was reduced to an average of 2.
3. Energy savings:  Our infrared technology is extremely efficient.  We will use less than half the electrical energy to heat dies vs. convection ovens.  Also, since the die is heated properly and evenly, there is now no need to overheat the first several billets just to heat the die.  Over heating of the first billets is not only a waste of energy but it also very hard on the die (bearings), not conducive to good finish quality and can jeopardize the structural properties of the extrusions.
4. Improved recovery:  As mentioned above, we heat dies VERY evenly, see graph.  This even heat will reduce runnout (aka rod length) variation.  We have all seen the first billet through a die to have a variation of 20 feet, the second billet – 5 feet and the third and remaining billets are even.  Again, what is happening here is that the die (by virtue of pushing billets through it) has become evenly heated.  If the die had been heated properly in the first place, recovery would indeed be higher.
5. Improved surface finish of extrusions:  The Novatec oven will heat (to 850f) a 16” x  6” die in 90 minutes.  This rapid heating reduces die bearing oxide to almost nil.  The same die in a convection oven will take at least 6 hours to reach tempurature.  Oxidation is a function of both time and temperature – reduce the time part of the equation and the oxide must reduce as well.  The infrared oven does not use airflow, as do convection ovens.  The airflow associated with convection ovens also damages the die bearings and deposits other oxides and impurities onto the die and die bearing, which, of course, ruins extrusion finish.