Filling vessel with Nitrogen
Filling vessel with Nitrogen
(OP)
Hi all...
We have completed a vessel (CS material) and we are now ready to fill it with Nitrogen before we store and transport it. Our client and we have a contradiction of how much should be the pressure of the Nitrogen. The time period that the vessel will remain sealed, is unknown. Does anyone know how much that pressure should be (we claim 0,1 barg) and if there is any part of ASME suggesting that?
Thank you all...
We have completed a vessel (CS material) and we are now ready to fill it with Nitrogen before we store and transport it. Our client and we have a contradiction of how much should be the pressure of the Nitrogen. The time period that the vessel will remain sealed, is unknown. Does anyone know how much that pressure should be (we claim 0,1 barg) and if there is any part of ASME suggesting that?
Thank you all...





RE: Filling vessel with Nitrogen
0.1 barg sounds a little low. In all likelyhood the nitrogen will leak slowly, especially when the vessel is transported. Thus it will need to be topped up more often once the pressure has fallen! On what basis did you arrive at 0.1 barg? ie: is this vessel rather large?
We are doing something similar and setting the initial nitrogen fill at 1 barg, to be topped up when it falls to 0.5 barg. These are for exchangers though and probably with much less volume than your vessel!
RE: Filling vessel with Nitrogen
ASME would not address this transportation issue.
I have had boiler/HX components shipped at 2-5 psig N2 blanket .
What is important in your decision is how long the item will be stored at the plant site and the possible danger introduced from the nitrogen.
Higher pressure simply costs more money and offers no more corrosion protection.
If .1 barg can be adequately monitored over the time of storage, I think it would be acceptable.
-MJC
RE: Filling vessel with Nitrogen
Cheers,
gr2vessels
RE: Filling vessel with Nitrogen
If this vessel is large enough for human entry there needs to be very visible signage that states the fact that this vessel is fill with N2 and needs to be purged and tested prior to vessel entry. I was witness to a fatal incident in a case where the N2 wasn't purged and tested prior to a vessel entry.
RE: Filling vessel with Nitrogen
suggest frequent monitoring during the storage period
RE: Filling vessel with Nitrogen
Also, correct me if I'm wrong but as far as I know, we would only require inert gas protection for sea shipment (or any sort of transportation) if the equipment is S.S. or alloy. If it is just c.s. then we won't need to do so since the rust coating is a natural protective coating. Am I right?
RE: Filling vessel with Nitrogen
I believe that large feedwater heaters and many other vessels are shipped with an N2 blanket by many of the major fabricators.
The N2 blanket for large expensive carbon steel "things" serves a contractural function. When the purchaser finally opens the vessel, he knows that the interior (with it's light coat of rust) is just the way it left the fabricator's facility and no degradation occured in transit.
For large expensive carbon steel "things" it is a modest additional cost.
-MJC