Oxygen Pressure Vessel

[mech8790]

Hi everyone!

I am looking for any special requirements of designing and constructing oxygen pressure vessels. The vessel needs to be pressurized up to 10 BAR and the operating temp. is -20 to 40 C. It is going to be tested and operating in EU so I am not sure which code should apply. Any special requirements to prevent the PV from contact with fire?

KR

 

[XL83NL]

Pure oxygen? As design code, EN 13445 seems the most straightforward choice to me (as it provides ocmpliance with the PED 2014/68/EU).

 

[mech8790]

Yes, pure oxygen, not in liquid. Can PD5500 be used instead? I am not sure does PD5500 comply with PED.

I have found this on the internet:

PD 5500 was formerly a widely used British Standard known as BS 5500, but was withdrawn from the list of British Standards because it was not harmonized with the Europeran Pressure Equipment Directive (97/23/EC). In the United Kingdom it was replaced by EN 13445. It is currently published as a "Published Document" (PD) by the British Standards Institution.

 

[XL83NL]

What MoC are you considering to use? I would use EN 13445, but PD5500 would work. Just requires a bit more work on the PED-side. Will the vessel be located in the UK?

 

[mech8790]

Hi XL83NL

Can you tell me what does MoC stand for? The vessel will be located in different EU countries, including the UK.

 

[XL83NL]

MoC = Material of Construction

 

[mech8790]

I have got in my mind 316 or 304 S/S but I am not sure is there a special requirement for a different material to be used. Is there any guidance for oxygen tanks/pressure vessels?

 

Just curious, would oxygen be considered 'lethal service'?

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[mech8790]

Yeah, good question. I think it may depend on pressure rating or is it in a liquid state (cryogenic). But, on the other hand, we use pressurized oxygen in the diving industry and what I know it is not toxic below a certain level of pressure.

 

[racookpe1978]

Not toxic directly of course.
But "technically" high pressure oxygen is also not "flammable" ... by itself.
It just makes anything around it flammable, or like the ulmar rubber seals used in the early X-1 planes, explosive if touching the oxygen.

All of the usual HP gas rules apply as they would on a high pressure nitrogen bottle (direction of threads, NDE, etc. But your fabrication and even cleaning instructions and painting and preservation instructions need to be explicit about what is permitted to be used: which solvents, what gaskets, what torques, etc.

 

[MGZmechanical]

Hi, EN 13445 is harmonized code. PD5500 not. On the other hand oxygen is dangerous fluid and you have to be careful about materials and internal cleaning. Any trace of grease in contact with oxygen can lead to an explosion. See

https://www.eiga.eu

(European Industrial Gases Association). They have a lot of info about it.

 

[Caloooomi]

As ManoloGalarraga said, you need to have you cleaning procedures up to scratch when dealing with a vessel that will be for oxygen service. EIGA Doc 33/06 or CGA G-4.1 are useful. Specific detergents etc. are to be used. 304 / 316 is fine for oxygen use, but checking the oxygen velocities within the vessel is good practice too.

Which recognised standard you use is up to you, ASME VIII is fine but EN 13445 "should" be the easiest as it is harmonised with PED. Again, for welding, ASME IX is fine but you need to jump through some more hoops to meet the PED requirements.

 

[tigny]

Hi, if you use EN 13445 you have more liberality to use different materials (more than use ASME.BPVC Code) since you can use materials within harmonized European Standards or materials with an European Approval for Materials or material with a Particular material appraisal.

best regards

tigny

 

[moltenmetal]

Oxygen is most decidedly NOT "lethal service" by any reasonable definition of that term. "Lethal service" applies to materials which will cause serious harm or death when leaked in even small quantities. That does NOT apply to oxygen. Oxygen does have hazards and does require some design effort- reference to the Compressed Gas Association (CGA) documents related to oxygen is the first place you should go aside from any local European rules which may also be in place. At 10 bar(g) the hazards are minimal.

 

[SnTMan]

This might be helpful.

Regards,

Mike


The problem with sloppy work is that the supply FAR EXCEEDS the demand