29 Aug 2000 at 10:19 pm #273431
Bungie, I don’t know if the codes are written the same way there as here – without the reason for pressures, etc. Do you know why the pressure reducers stage down from 200 psig to 100 that way? Is that because the cast iron can take those pressures with a safety margin in the sizes that can handle the flow?
30 Aug 2000 at 2:14 am #287643
Harold when you say “cast Iron” are you talking Rated cast Iron fittings?
Many of the “cast Iron” fittings that I use have a rating of 250 PSI STEAM. (400 WOG)Even though I use them for fire supression work (Sprinklers and stand pipe.
Of course cast steel I could go much higher
If steam pressure is your concern you could use forged steel with a working pressure 3500 PSI.
30 Aug 2000 at 2:34 am #287644
I was more interested in why Bungie’s code settled for those numbers. They are nice and even and sometimes work out to 100% safety margin; but I just wondered if that was their idea.
But since you volunteered, are our codes designed the same way? In heating we rarely use cast iron now except in some city work.
30 Aug 2000 at 9:10 am #287645
The hot water is all in copper, with, in this case, steel tank for the hot water.
30 Aug 2000 at 9:16 am #287646
As for the pressure settings …Sorry, but I dont know the exact reasons
30 Aug 2000 at 9:12 pm #287647
Harold, what is this nonsense about “We rarely use cast Iron except in city work|”
WHO IS “WE”?
I being a licensed Master plumber AND Licensed Master Fire suppression piping contractor STILL specify Cast Iron fittings for all my Steam and Sprinkler piping work.
Yes, a lot of folks use malleable black for heating and some morons even use cast fittings for gas work BUT this isn’t the Normal way to do piping.
The reason I personally like “steam fittings” is the ease of breaking them out even after 80 years of service. Think about ACCESS allowed by the ease of breaking out this type of fitting. AND the beauty is the steam fitting is not only better BUT slightly cheaper.
Malleable fittings can be used BUT on steam BUT the higher acid concentration on the return line can eat away at the much thinner wall of the malleable fitting then the cast counter part.
There is a sound argument for the use of Malleable fittings as opposed to cast like the less chance of sand casting holes BUT the stress put on the malleable fitting with expansion far out weights this when leakage is concerned. Cast Iron lasts and lasts
I like using the malleable (black) on gas and oil lines and even pneumatics for certain types of equipment.
Oh well to each his/her own AT LEAST we both agree NOT TO use “copper” on steam right?
30 Aug 2000 at 10:13 pm #287648
Yes, Sylvan. We (as in personal preference) can agree to use cast iron for low pressure steam.
Other more royal, We, will use copper. Some fellows in Brooklyn and New York I know have used copper for generations. I ask them to use threaded adapters in swing joints if they must; room to steam temperature swings that work copper back and forth at solder joints tends to make it easy to remove fittings also, but you can’t predict the time of removal.
31 Aug 2000 at 12:57 am #287649
Youre both wrong in this. Cast iron steam fittings only go in the city. Nobody has put them in houses outside of a few big cities since before Sylvan was born last century. Ask Dan Holhan in his book Dead Men.
New heating men wouldnt be caught dead putting steam systems in anyway; the standby losses and no zoning makes it a waste in more ways then one.
The new heating men would braze the whole system together with copper like an air conditioning system. Then they would evacuate all the air out of the system so water would boil at 140 degrees F. There would be no rust like cast iron, no air inside to corrode and less losses. They would do this if anybody really put steam in houses anymore.
These old guys just like to make cave-man rust buckets at big cost.
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