High Temp. & High Pressure Blower II
Further to the 2012 post "High Temperature Blower at Work"and 2011 post "High Pressure & High Temperature Industrial Blower"; NXT Roasters has been working on an air bearing package that will deliver the same pressure and volume but at higher temperatures.
High temperatures create a hostile environment especially to an object that must turn at high speeds. Materials must be carefully chosen so that they will maintain their strength and hardness at the elevated temperatures. Thermal expansion creates problems as well because not only do different materials expand at different rates but various components operate at different temperatures. That "constant" X 10-6 per °C can really bite you.Common bearings can handle high temperatures and high speeds but rarely can they do both in the same application. The high speeds (above 10,000 rpm) mean that the components have to be dynamically balanced plus tight tolerances have to be maintained.
The initial goal was to place the Blower in the coffee roasters where it should easily cope with the 250°C recirculated air. Curiosity drove the project to higher and higher temperatures. The current temperature ceiling will remain until a stainless steel housing is fabricated.
Earlier this week a blog reader requested information on a blower capable of moving flue gases. Unfortunately the 800°C flue gasses are 300° higher than we have been running the Blower, that temperature is beyond the capacity of the 6061 Blower Housing.
There are some obvious applications for the Blower but it would be interesting to find out if it is able to solve or enhance some industrial processes. Email your suggestions and requests to main@nxtroasters.com . Perhaps our development plans will coincide.
In the meantime we will continue to accumulate operating hours.
