Does a Flame Arrester meet intent of Open Flow Path per ASME Sec. 8? 5

[chemter]

ASME Section VIII, section UG-127 (d)[Open Flow Paths or Vents], states that "Flow paths or vents, open directly or indirectly to the atmosphere, may be used as the sole pressure relieving device on a vessel."

Does a flame arrester meet the intent of this section? Curious how other engineers interpret this. Thanks.

 

[moltenmetal]

Yes, in my opinion it does.

 

[don1980]

Yes, it's perfectly OK for a Sec VIII vessel to have a flame arrestor on an atm breather pipe. There's nothing in Sec VIII that even hints that this isn't OK.

You just have to size the line and account for the flow resistance of the arrestor.

 

[moltenmetal]

Do be aware that a flame arrestor can, in some services, become blocked with ice or other similar issues can occur. But properly designed and specified, you can treat it as an open flow path.

 

[RaRo]

On my site for direct atm. vents with flame arrester we justify (and trace) the clean service, or ensure it either using heated jacketed pipe+flame arrester or frequent inspection/cleaning.

 

[786392]

Dear chemter Hello/Good Afternoon,
Actually the service conditions and environment plays havoc at times
since we fail to address even minor changes through a proper " mangement of change procedure" fulfillment.

It is the out come of such changed circumstance/service of more fithy and dirty nature than the original design parameters which deteriorates the flame arrestors functioning through clogging of sticking material onto the surfaces thus the actual "openness feature gets practically defeated"

We suffered an storage tank's top shell roof perphery seam joint failure due to similar changed service outcome
It's (the atmospheric tanks) flame arrestor installed vent got in a way blocked and
Tank got over pressurized but only the weak top joint gave way& tank was saved as per API 650 code of single fillet weld.

Hope this proves helpful.


Best Regards
Qalander(Chem)

 

[BenThayer]

our site is not consistent. some are and some are not.

it is not uncommon to have a CBV with a flame arrestor and a graphite disc at low pressure in parallel.