Free vent on pontoon manholes of EFRT

[Syahar1975]

Good afternoon Tank Builders,

API 650 appendix C for EFRT, clearly states that pontoon manhole shall be equipped with goose neck free vent.

I have a case that the tank designer decided not to provide that free vent on pontoon manholes.

I have raised this issue to the tank designer and got their confirmation free vent is not required on pontoon manholes.

I understand as tank designer sometime their design is not exactly follow the code and they reserved the right to do that.

I my self have never seen in my previous projects pontoon manhole without free vent.

Any comments ?

 

[IFRs]

If the manufacturer intends to certify that the floating roof is built in accordance with API, the manway covers need to be liquid tight and include a hold-down device, vents are required for each compartment but don't have to be in the manway covers although that is typical. You can ask the designer how they comply with API 650 Section C.3.5 paragraphs 1 and 2. If the owner agreed to the variance then there is no longer a question for the manufacturer. If the variance was not discussed prior to the installation, it goes to the lawyers. It's a small item of relatively low cost, easy to retrofit if needed and should not become a major issue in my opinion.

 

[Syahar1975]

IFRs,

Thanks for the comments.

What I do not understand with the design is, we have a name plate on this tank and this name plate was designed in accordance to API 650 standard. But in fact our tank design does not follow the clause as stated in your respond email.

In my opinion if we have API 650 name plate we have to follow minimum requirement as required by API 650.

 

[IFRs]

Sometimes, small things get overlooked, or pass unseen.
Now they are in the sunlight and need to be ignored again or fixed.