1 reply to this topic

[kkala]

i have an existing AFFF system for our fuel tank farm which the piping needs to be changed because of corrosion. the pipe fittings in the fuel tank farm are either welded or flanged. I would like to use victaulic fittings instead when replacing them. Is it a requirement to have the pipe fittings welded and/or flanged? I looked through the NFPA 13 book but could not find any mention of pipe fittings need to be flanged or welded if located in a fuel tank area. Does anyone know the answer to this?

I have taken opinion from a colleague performing firefighting design process wise, i.e. determining pressures / flow rates, but not familiar with mechanical design. Conclusions are as follows.
1. Specific requirements for welded or flanged or threaded piping for fire water has not been traced in NFPA books, but this needs detailed investigation. Probably all types are permitted in general, e.g. NFPA 31 for fuel oil piping refers gaskets, pipe connectors, threaded joints (no cast iron fittings). If these are permitted for fuel oil, why not for water?
2. Assuming this, cooling ring with sprays around tank had better be flanged, to be dismantled from time to time for cleaning. Underground pipes had better be welded to avoid leakages as much as possible.