Pipeline safety valve setting

[galata]

Hi all,

Could you please tell me how to calculate pressure safety valve settings.
Pipeline will be hydraulic tested with sea water at 125 Bar. According to the procedures we will install Pressure safety valve. My question is what pressure should safety valve be set on.

Regards

 

[athomas236]

I would expect the design code to cover this issue.

Regards,

athomas236

 

[BigInch]

Your mechanical/piping/hydraulics/ engineer will be able to do that. Its his job to specify that setting. What's the PID say?

Never the less, it depends on the code and your maximum allowed operating pressure and whether a particular overpressure level meet a specified transient allowance, or if it must be vented.

**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[galata]

According to the P & ID design pressure is 99 Bar. Test pressure is 125 Bar.

Design code is API PR 1111

 

[BigInch]

That's a "recommended practice", "RP", not really a code.

But in any case, the PID should state the relief valve set pressure, whether it is provided by the vendor, or the pipe designers.

If the relief is provided to protect the pipe, and the code is B31.3, and the overpressure value and duration in time could be classified as a transient pressure, it might fall within the piping allowable pressure + transient pressure level and not need a relief valve at all... for the pipe.

Are you protecting the piping or the equipment? If the equipment, call your manufacturer. If the pipe, see your pipe design code. And make sure the piping engineer agrees with whatever you finally decide.

**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/