3 replies to this topic

[process85]

Hello All,

 

I have a query regarding re-rating of an existing PSV. If I have a PSV for which I know only the designation, for eg 8T10. I don`t have the process data for which the  PSV was originally designed

 

Now I have an independent new system for which I have the required relief load based on which I estimate the PSV orifice area.

 

Can I say that, if the area calculated for my new process service is lower than the area for T- orifice, then the above mentioned PSV will work for my new system. Or do I need the old process data that was used for the design of existing PSV as well. If yes, what additional help the old process data will provide.

 

Please help.

 

Thanks

[fallah]

 

Can I say that, if the area calculated for my new process service is lower than the area for T- orifice, then the above mentioned PSV will work for my new system. Or do I need the old process data that was used for the design of existing PSV as well. If yes, what additional help the old process data will provide.

 

 

process85,

 

How much is the calculated area lower?

 

Old process data cannot help anymore; you should have the data sheet of PSV and all hew process data to evaluate if the PSV can be applied to new process service in material, pressure rating, orifice area,    standpoints...
 

[process85]

Thanks Fallah for the response.

 

The situation I explained above is a hypothetical situation with an example for better putting up my point. Ofcourse, the new area has to be sufficiently lower than the area for T-orifice in order to confirm if the existing PSV shall work for the new system as well.

But in summary I just wanted to know if I need the existing process data for the original design of PSV when rating the same PSV for new service and I guess your response clearly explains that it is not required.

 

Thanks

[fallah]

 

But in summary I just wanted to know if I need the existing process data for the original design of PSV when rating the same PSV for new service and I guess your response clearly explains that it is not required.

 

 

process85,

 

Yes, I meant existing or old process data to evaluate the PSV for new process conditions isn't necessary....