Regarding C.I. butterfly valves

Hi...a bolted connection between CI & SS flanges does not pose any problem. By the way whats the valve dia?

AKT

There are quatities in te range of 100NB and 600NB

Good morning Nithya, I would not hesitate to design 2 RF steel flanges mating to a CI butterfly valve, but I would not do the reverse, i.e., 2 CI flanges mating to a butterfly valve.

You need to be careful when mating cast iron flanges to raised face steel flanges - usually the CI flange is flat and when it is tightened against the raised face it torques over and can lead to cracking in the cast iron body.

When this needs to be done it is usually recommended to machine the steel flange flat and install a full-face gasket.

Whoops - I see that the question was regarding wafer or lug style valves - so the raised face issue may not be present - unless they are threaded lugs.

So now my question is - what style do you actually mean? Wafer or threaded lug?

Where are you purchasing this Butterfly Valve from,the neighborhood drugstore or gas station? Doesn't anyone buy from a manufacturer or company that is in the valve business and can spec the right valve for the specified application,use your head buy from someone or some company that knows valves and can spec it the correct way,you get what you pay for,DO IT RIGHT THE FIRST TIME and save time, and time translates into money.

well, obviously im not gonna purchase the butterfly valve from a local store!:-) Right now im drafting the specs to send to prospective vendors and wanted to be sure on my side... so the question.

Anyway, its a lug style butterfly valve that i am purchasing. and from the discussions here, looks like there shouldnt be a problem in installing it between RF steel flanges. The raised face will probably be machined off or i may ask for a spacer to make the face flat.

thanks,

Hey guest register.

Nobody buys butterfly valves at a drugstore. Get a life.