S.S. Flex Connectors to Brass or Bronze

Rob_7

I was putting a stainless steel flexible gas connector on a water heater the other day, and the instructions read (no surprise) to keep dissimilar metals isolated from each other.
This particular connector had stainless flare nuts and flare to thread adaptors included. Also, I noticed some brands of these connectors apparently have brass flare nuts right on the stainless, i.e., no integral dielectric separation. My questions are, Since these things generally go directly onto a brass or similar material gascock, or else iron which itself is generally attached to the gascock, how the heck are you supposed to "keep disimilar metals isolated"?
Has anyone had any problems with corrosion doing this, or know of any codes or alternate reccomendations for this type of hook up besides putting the stainless flare nut right onto a flared brass valve?
What about a brass valve in the iron pipe whether it touches stainless or not, isn't that disimilar metals, too?
Thanks.

hot_rod

The only way for corrosion to occur

between dissimilar metals, there has to be moisture or water present, an electrolyte. Think of a wet cell car battery, no energy is created until the acid is installed.

In fuel line connections steel to aluminum at the gas valve, brass and steel. brass and aluminum, ocassionaly galvanized components, stainless steel, and commonly copper (copper is an acceptable material for fuel gas) is in the mix. They all work fine together in a dry enviroment.

hot rod