Can anyone tell me if Umbrella type roofs can be used when the design pressure requires anchorage and as a result the tank must apply Appendix F section 7?
In API 650 we are told that F7 tanks must have their roofs and roof nozzles and manways designed as shown in API 620. There are no design...
Gentlemen,
If you review the proposed Addenda 1 to API 650 11th Edition, available at the API website, you will find that instruction for frangible joints in tanks less than 50' is included. This addenda is not yet issued, but should be issued in the not to distant future.
TankDude,
I think we are essentially doing the same thing. If there is no pressure on the tank, F.4.2 does not enter into the calculation. Where there is pressure, if this limit is not applied, there is always a negative value. In the designs I have done recently using the limit, F.4.2 does...
Gentlemen,
A. How to apply 5.2.1.j.2?
1. Calculate value for F.4.1
2. Convert F.4.1 * 1.6 to moment
3. Calculate moment resulting from pressure Mpi 5.11.2 (could be zero)
4. Calculate moment from horizontal wind
5. Calculate moment from vertical wind - but not greater than (moment from...
We have asked this question of API 650. Below is the response.
From: Gordon Robertson [Robertsong@api.org]
Sent: Tuesday, November 14, 2006 12:13 PM
To: John Walters
Subject: RE: API 650, Tenth Edition, Addenda 4, Paragraph 3.9.7.1 Note d.
FW: API 650, Tenth Edition, Addenda 4, Paragraph...
In paragrapn 5.10.4.7 a. of the new 11th edition, there is language for distribution of column loads. Does anyone know, is it intended that the product load plus the bottom plate load would be deducted from the soil bearing capacity resulting in the load available for the column load distribution?
kybalu,
You should have started another thread with your question. However, since I was interested in this thread, I have read your question and will respond.
In API 650, tanks built with group 1, 2, or 3 materials that exceed 1" in thickness are required to have nozzles 12" in diameter or...
SJEC,
Even back in the 1960's API's position was that tanks built to the minimum requirements of the standard could withstand 1" water vacuum without anything additional. If you can find API on the nameplate, a nameplate drawing, or find the certification letter certifying that the tank was...
So, if I understand, although we calculated uplift on the roof, we use the result as the moment in the calculations for overturning. Is this correct? If so, then I presume that this value, Mw, would also be used in the evaluation of anchor bolt tension, 3.11.3, and anchorage, 3.12.2. Is this...
We have an 87' diameter tank with an umbrella roof. The roof radius is 70'. On the roof, the client desires to place a 10' x 10' platform adjacent to the stair top platform. As a result, the platform will not be at the apex of the roof, but over just two formed plates. Typically, we would...
Does anyone know of a good reference source for formula to determine effect of installing eccentrically loacted roof top platforms on Umbrella or Dome roofs?
The intent of this requirement is to provide liquid tight compartments. In the design condition where two adjacent compartments are flooded, you could see sufficient sag of the roof to allow flooding of adjacent compartments across the top of the compartment bulkhead. The specific design would...
Be careful here. Although the minimum is stated in API 650, for constructability, you would want to have a minimum of 2'. If you don't, especially on thin steel, you will increase your chances of peaking and banding problems in the intersections.
We have just been advised that the new 11th edition will be available the last week in June of this year. Normally, that would mean that it becomes mandatory the last week in December this year.
