[ spring selection for 2 phase flow ] 1

[gguliye]

Hi All,
i have a request for AG 800 valve and it is 2 phase flow. the customer doesnt know exactly the gas density so it prevents me from sizing. however, the valve is like to like replacement, so i have an orifice size already calculated. should i be so strict on gas density? will it affect anything else apart from orifice size? i am really suspicious about the spring selection, which spring table is used for 2 phase flow gas one liquid one?
thx in advance
regards,

 

[Latexman]

I don't know about springs, but for the flow coefficient of the valve there is very little test data on 2 phase flow. The most common advice I see is use the gas coefficient for 2 phase flow.

Good Luck,
Latexman

 

[The Obturator]

If it is a like for like replacement, then what is the issue? You just provide the same. In which case, the original paperwork will provide the data. But why are you concerned about sizing if it is a direct replacement?

For spring selection of 2 phase application, it is a factory selection. But this would not have changed for a like fr like replacement.

Per ISO-4126, only the term Safety Valve is used regardless of application or design.

 

[gguliye]

Obturator,
i dont have the serial number to check it out. thats why i am asking

 

[The Obturator]

Yes, You need to ask your client for it. He wants a like a like replacement, then he needs to provide the info. No telling what other specialities are involved.

Per ISO-4126, only the term Safety Valve is used regardless of application or design.

 

[gguliye]

thx

 

[don1980]

Two-phase relief streams are compressible. So, when there's a binary choice of gas or liquid, 2-phase designs fall into the gas category.

 

[Latexman]

Don,

Well said! I want to be like you when I grow up.

Good Luck,
Latexman