What service conditions would require the use of a bottom slope of the floating roof pontoon instead of a flat bottom? I have seen both used in industry.
https://files.engineering.com/getfile.aspx?folder=4142ddf1-a2be-4cfa-bf54-1b54485da7c4&file=Pontoon_Shape.png
Since you are building a water tank you could run your current design through AWWA to see if you could pass it through that standard. I don't believe PWHT is required. However the design stress for A516-70 goes down so you would have to reduce your liquid height. Probably going to be painful if...
What is the largest API 620 flat bottom tank you have seen built?
I have been asked to design a 50' diameter tank to API 620 with a design pressure of over 10psi. The required anchoring on this will have to withstand close to 3,000,000 lbs!
Has anyone built a flat bottom tank with this pressure?
API 650 does not require RT on the annular plate butt welds if the annular plate is used for reasons other than 5.5.1 or M4.1.
See attached for an old 650 interpretation that alludes to this. If the annular is there to satisfy 5.5.1 or M4.1 then RT is required. If the annular is there for...
I would agree with Fegenbush, best to replace the manway. While API 653 does not directly address holes in the necks of manways it does state that the minimum size of a shell patch plate shall be 12" (9.2.2.1). It will also be difficult to meet weld spacing requirements (Fig 9.1). These don't...
Thanks for the input.
I have seen the chart in API 650 that shows the temperature ranges in Canada but it doesn't agree very well with the published data in the National Building Code. (The NBC tends to have a warmer low temps than API 650. Example, Edmonton Alberta NBC -29F VS API 650 -43F)...
In the National Building Code of Canada the lowest January temperatures are given for locations across Canada. These low temperatures are reported as having a 1% chance of being exceeded. Does anyone know how this would compare to a lowest one day mean temperature?
In the National Building Code of Canada the lowest January temperatures are given for locations across Canada. These low temperatures are reported as having a 1% chance of being exceeded. Does anyone know how this would compare to a lowest one day mean temperature?
Quick question. Are vessels still required to be U - stamped? I see in the new Code they now have an ASME stamp instead. I don't deal with a lot of vessels anymore but I just received a vessel with a U stamp and I am being told that it is no longer a valid ASME stamp.
There is a formula in table C.2 in API 12F for a free vent that you could use.
Q = 1667 Cf A (Pt-Pa)^0.5
where
Q is the venting capacity in standard cubic feet of free air per hour (SCFH);
Cf is 0.5 (the flow coefficient);
A is the hatch area in.2 (A = 44 in.2 for 8-in. round hatch);
Pt is...
In short if your tank is anchored (or you add anchors) and your anchors can hold your new design pressure you can ignore F4.2 as it is a check for anchoring as mariog was alluding to.
Note that in Sect 8.1.2.9 that it states that the RT is only required if the annular is required per 5.5.1 or M.4.1. Often an annular ring is installed on a tank even though it is not required per the 2 sections mentioned above. In this instance I would argue that API 650 does not require you...
The MAWP for an atmospheric tank is not 2.5 psi as stated above.
Without knowing anything else about your tank the MAWP would equal to the weight of the roof plate as you originally stated. Just because the tank has been operated above its original design condition doesn't mean it should be...
I think that the only way 5.11.2.2 makes sense is if 5.11.2.1 does not apply to unanchored tanks with supported roofs. It would be nice if the scope of 5.11.2.1 had been limited if that was the intent.
Hi All,
Just looking through the new edition of API 650 and I was wondering if anyone can answer the following.
There is additional overturning criteria specified in Sect 5.11.2.1 and 5.11.2.2. Does anyone know if 5.11.2.1 is applicable to unanchored tanks with a supported roof? If you have...
