mainly used for comfort heating in the baseboard type heater market. The market has standardized on .315 diameter x .035
wall material aluminum 3003 seamless heaters are used in the full hard condition. Fins are applied and staked to increase surface area.
Maximum recommended watt density in air is 30 with fins, 6 without fins.
used in areas where corrosion is not a problem
and where sheath temperature does not exceed 650°F. Bundyweld is basically a steel tube and is fabricated by rolling a steel strip into a tube
and copper gives it its color and has the added benefit of preventing corrosion while being stored. It is used for the following applications:
1 - Aluminum cast in heating
2 - Low temperature air heating
3 - Oil immersion heating
4 - Alkaline immersion heating
5 - Salt bath immersion heating
Because of its copper content it should not be used in atmospheres of ammonia as the chlorine will attack the
Used almost exclusively for water immersion heating. Maximum sheath temperature in air
300°F. If subjected to higher temperature it will oxidize away rapidly. In immersion water heating, watt densities of
100 w/in.² have been used, for commercial water heating we do not recommend watt densities of greater than 60
Used in air heating and immersion heating in water and chemicals that will attack other less expensive materials. It is the
highest temperature material that we stock and will cover 95% of all the air heater applications.
Incoloy 800 is also designated stainless steel alloy 332. It is superior to stainless steel in most heater applications.
There are a few applications where stainless steel will outperform. It is composed of the following: nickel,
chromium, iron plus trace elements.
This is a relatively new material that has been developed as a lower cost material than the 800 material. It is presently
finding use in air heating applications where it has shown to be superior to 800 in its scaling resistance. Other applications are being
determined. It is composed of nickel, chromium, iron plus trace elements.
This material was the most widely used for air heating applications, but has been replaced by incoloy 800 because of its cost.
It still finds use in areas of extremely high temperatures 1700°F + and corrosive environments. It is composed of nickel, chromium, plus
Stainless Steel 304
This material finds use in food cooking applications, and is air heating where sheath temperature is below 1200°F.
The 300 series material is subject to carbide precipitation and for that reason it should not be used in corrosive environments where the
sheath temperature is above 900°F. It is less costly than incoloy and should be used in areas where it will perform as well. Stainless steel
should not be used in water heating as it will corrode. The 304 material is an austenitic grade and is composed of chromium, nickel, iron
plus trace elements.
Stainless Steel 316
It generally has the same features as 304 material but because of its molybdenum content it is more corrosive
resistant to some chemicals especially in the photographic chemical field. It is composed of chromium, nickel, molybdenum, iron plus trace
It is used in the same areas as Bundyweld. Because of its tendency to rust in storage, it requires extra cleaning. It is somewhat
higher in cost than Bundyweld as we do not purchase it in as large a quantity.
This material is used primarily in immersion heating of highly corrosive materials such as acids. It is the most costly of the
sheath materials mentioned.