Inflatable duct balloons can be inserted in any size duct work and perform much better than wood frame and plastic barriers. They are constructed out of a durable wear resistant fabric rated up to *400°F (204ºC) and can be reused outage after outage. They are designed to collapse down small enough to fit through most existing man ways for ease of installation and removal. Using the supplied 120V blower system,
they can be installed quickly and become fully inflated in ten minutes or less. They can be quickly removed from the duct work by turning off the blower and then opening a large zipper. Applications are in SCR’s, FGD Scrubbers, Gas Turbines with HRSG Exhaust Stacks, and many others.
*Fabric selection is based upon the type of application, operating temperature and duration of intended use.
*Fabric selection is based upon the type of application, operating temperature and duration of intended use.
This is a 24’0” high x 20’0” wide x 3’0” deep duct balloon being tested before shipment. It will collapse down small enough so that it can pass through an existing 24” x 30” man way. It weighs about 95 lbs and inflates in less than four minutes.
Duct Balloons
Reduce Maintenance Cost
This is a 36’0” wide x 14’10” high x 3’0” deep duct balloon installed in a FGD scrubber outlet duct. It weighs <100 lbs. and can be installed in minutes. Due to the leaky isolation damper, it is used down stream (on non-gas side) of it during inspection and maintenance of the FGD absorber on an annual basis.
Due to plant cycling, weekend shut downs may occur many times during one year. If the plant will be down for a few days, a stack balloon can be inserted inside the exhaust stack after a 24 hour period to keep the residual heat “bottled up” inside the HRSGs. Some plants use a combination of duct balloons at the front end and back end, and sometimes at the back end only. The location on where to use them are based on the operating cycles of the plant, geographic location, corrosion prevention goals, etc.
*HRSGs that sit idle for extended periods of time are at risk of gas side corrosion from the humidity in ambient air. In North America, HRSGs tend to sit idle more frequently in the fall and spring, which also
*HRSGs that sit idle for extended periods of time are at risk of gas side corrosion from the humidity in ambient air. In North America, HRSGs tend to sit idle more frequently in the fall and spring, which also
coincide with wetter weather, increasing potential for damage unless preventative action is taken. Rain water and humidity entering through an open stack helps drive the corrosion process. Another driver is the change in ambient temperatures between day time and night time, where tube metal temperatures lag behind the daily high ambient temperature. When humid air contacts the cool tubes, condensation can occur, causing corrosion. This can be considered another form of “dew point corrosion”, except that entire sections of the HRGSs typically are affected, not just a few rows of preheater tubes receiving cool feed water. *Excerpt from the HRSG Users Handbook, 2nd Edition (Chapter 9.1), distributed by the HRSG User's Group.
