When investing in a flue gas filter, the customer must decide which type of cages to go with the filter. It can be a AISI 316 cages which is made of stainless steel, or it can be the cheaper black steel cages.
Price is not the most important factor here; it is the type of application the filter is handling as well as the humidity of such application.
As a rule of thumb, we in Teldust always recommend AISI 316 cages when dealing with flue gas filters, but in some cases black steel can be acceptable though.
When choosing black steel cages, the expected chemical composition of the exhaust gases is of great importance here. Black steel cages are not suitable for applications where acids are present, and the humidity is higher than 15%. Instead, black steel cages can be used for dry biomass combustion like straw and cleaned wood waste.
It is also important to be aware of the compressed air quality when cleaning the filters. If using black steel cages, the dew point must be between -30 to -40 deg. C otherwise you risk corrosion.