Does anyone have any advice regarding steps to take when evaluating new shell nozzles that have been installed in a tank and that do not meet current API-653 weld spacing criteria?
To my knowledge API-650 doesn't provide a recommended max loading for the standard scaffold hitch. Before I jump into the process I was just wondering: has anyone ever taken the time to calculate it and if so what was the result?
I can't find anything in API650 or 653 that discusses required offset between shell vert welds and bottom plate lap welds. Specifically, regarding a bottom replacement. I have always tried to use 12" when designing and detailing new construction, and this was just a rule-of-thumb that someone...
Below Table 2A of API2000, Note d states that tanks with a capacity greater than 180,000 bbl require individual study. It then refers to Appendix A for more information about the basis of this table, however this Appendix is very non-technical and simply mentions that a thermal evaporation rate...
I am design a structural cone roof for an API-650 tank and I am using A992 structural steel. Since API-650 doesn't appear to list this material (nor it's predecessor A572), I am a little confused about the design stress that I should use. API620 lists this material as having an equivalent...
I am analyzing a small silo with a cone bottom that is being supported by four columns. The cone has a compression ring located approx. 1/3 down from the straight shell to cone junction that consists of two circumferential plates with stiffeners located where it rests on the columns. I have...
I am trying to determine the maximum allowable working vacuum for a flat-bottom ground tank. In the past I have used Jawad's method for determining this, however since Add. 4 of API-650 has added App. V I am wondering if this would be the better approach. The design vacuum for the tank is 0.25...
Does anyone have any experience with the use of bottom sumps on tanks in jet fuel service? I have typically seen these tanks utilize floating suctions. I have concerns with a bottom sump due to product impurity. I would appreciate any comments that anyone may have.
Thanks.
I would greatly appreciate if anyone would comment or provide their opinion regarding the following matter: should the annular plate inside projection calculated in appendix E of API650 Add. 4 be taken as the controlling required projection when greater than that taken from section 3.5.2? I am...
API 650 provides recommended draw line/sump size combinations but doesn't really elaborate on how these were derived. I understand that the sump should be of adequate depth to prevent the suction line from pulling air out of the tank, however, can anyone tell me of a quick way to check this or...
I know this has been visited before in this forum, but has anyone learned anything new regarding the method for adding wind uplift to the overturning moment per Add. 4? It has appeared to me from the beginning that this value needed to be reduced (along the lines used for geodomes), however it...
It appears to me that equation E-20 is missing a reduction factor. The resultant calculation for this center of mass is much greater in all the trials that I have ran than that calculated in equation E-19. The value has often came out to be larger than the tank shell height. Under the right...
Can anyone tell me where to find the value for TL as specified in Appendix E of API 650 Addendum 4? Section E.4.9.1 states that unless otherwise specified it shall be taken as the mapped value in ASCE 7. I can't find it mentioned specifically anywhere in ASCE 7. Should I just use a value of 4...
Can anyone tell me or hypothesize as to what is the controlling factor for the location of drawoff sumps relative to the tank shell per API 650? I have a client who wants to use a 6" draw line with only a 24" diameter sump, and after unsuccessfully trying to convince them to use a larger sump I...
Section 2 of API-650 states the maximum plate thickness allowable for each different material and grade. For most materials it is allowed to use thicker plate for inserts, however for A573-70 (2.2.2(g)) it states that 1.5 inches is the maximum period. I was wondering if anyone knows why and also...
I need some qualified opinions on the following: there is a note at the bottom right of page 3-39 in API 650 that states (in relation to top wind girders): "For tank diameters over 200 ft, the section modulus required by the equation (from 3.9.6.1) may be reduced by agreement between the...
