Oxygen Piping - PIP limitation

[Ashwani_Mech]

Hello Everyone,

I would like to get some insight on why PIP limits the pipe size for oxygen piping to 12 inches.

Does anyone know what is the basis for this limitation for oxygen piping?

Thanks & Regards,
Ashwani

 

[LittleInch]

PIP??

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[XL83NL]

You mean PIP?

 

[hacksaw]

If you are talking about plastic piping (PVC) the size limitations has to do with strength.

Oxygen piping is another matter, and you need to specify your design requirements, pressure, temperature, run length, hazardous area class, etc., etc....

 

[Ashwani_Mech]

hello,
I am writing a piping specification for one of my client for oxygen service.

I am curious about the Process Industry Practices standard (PIP) specification which mentions sizes and material for various pressure system to be used in oxygen service. For eg:- the PIP spec - 6SA0B05, Class 600 , 304/304L SS, oxygen service, lists only pipe sizes up to 12 inches only. Please see attached snapshot.

I haven't been able to find a clear answer what is the limiting factor on the pipe size.

I would appreciate if anyone can share their input on this question.

 

[LittleInch]

It doesn't limit the size, it's just they haven't bothered calculating the size for anything bigger.

The PIP standards are really just start documents which allow you to use them as a base and modify accordingly.

You often find this with Piping specs - basically they only calculate the thicknesses etc for the pipe sizes that they can see on the particular project they are looking at. Often pipe ranges are missed out.

I don't know what the notes say, but are probably fairly anodyne.

A pipe size of >12" in Oxygen service sounds pretty major to me.



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Ashwani_Mech]

Thanks, but I have referenced other operators specifications and they also limit it to 12 inches.

I read the EIGA document for oxygen piping and pipeline system and that only gives limitation on the velocity of oxygen in the pipe to applicable pressure rating system. (See attached)

My closest take on this is to regulate the quantity of oxygen present in the pipeline system at any given point of time and that would be a probable reason why a size limitation would be put. But, at this point I am just guessing in a cloud of possible answers.

 

[jari001]

I looked at appendix E of the EIGA document, and it may be that above 12" the recommended minimum safety setback distances become subject to a more detailed analysis, so to keep things simple maybe a limit of 12" is recommended?

 

[GD2]

What piping material are you planning to use? Oxygen is gaseous and I would believe the size limitation is due to stored energy level.

You know carbon and low alloy steel materials are flammable even at low pressure oxygen (>15 psig).

Many factors effect the likelihood of combustion and ignition in oxygen service including velocity, flow, pressure, temperature, cleanliness, piping layout, impingement etc.

You have grabbed a good base document and build your specification from there.

Good luck!!!

GDD
Canada