Recent content by garry2

Using your formula for a duct balloon that measures 20' high x 15' wide x 3' deep: A (210 sq. ft) * (Pb is 10" w.g. - Pa 5" w.g) Then Fn = 1050? :confused: I'm lost! :frown:

Yes, you are correct. When the duct balloon is fully inflated its surface will press up against the carbon steel surface. It would be great if someone could help me calculate what type of differential pressure it would take in order for the duct balloon to loose its grip and start to move.

I did some research and the following are the coefficents of friction: Balloon materila is a 420 denier nylon = .43 Duct work is carbon steel = .60

We have developed a new product for an industrial application in large air ducts. The product is called a "duct balloon" which is a portable inflatable device that is equipped with a 110V positive pressure blower that operates at 10" w.g. The blower must remain on at all times to keep the...