Div 1, Code Case 2695
Div 1, Code Case 2695
(OP)
thread292-308650: ASME VIII-1 Code Case 2695
TGS4, reference to the old thread, Does Div 2, 4.5.2.1 apply to Div 1 with code case 2695 for nozzle design ?
In Div 1, it seems no limit for nozzle opening major to minor ratio. We have many hill-sided nozzle, especially for horizontal drum with 2" level instrument nozzle that has to be at very low or very high. We also have tangential inlet nozzles. All these nozzles ratio of 1.5 is easily exceeded. But in Div 1, there is no restriction. So I am wondering if code case 2695 is apply, shall I comply with 4.5.2.1 ?
TGS4, reference to the old thread, Does Div 2, 4.5.2.1 apply to Div 1 with code case 2695 for nozzle design ?
In Div 1, it seems no limit for nozzle opening major to minor ratio. We have many hill-sided nozzle, especially for horizontal drum with 2" level instrument nozzle that has to be at very low or very high. We also have tangential inlet nozzles. All these nozzles ratio of 1.5 is easily exceeded. But in Div 1, there is no restriction. So I am wondering if code case 2695 is apply, shall I comply with 4.5.2.1 ?





RE: Div 1, Code Case 2695
RE: Div 1, Code Case 2695
RE: Div 1, Code Case 2695
RE: Div 1, Code Case 2695
This is heavy wall horizontal vessel with integral nozzle. The ratio does exceed 1.5 for this level nozzle.
4.5.6 is for hilled sided reinforcement calculation that can be easily taken care of. But not sure if I have to comply with 4.5.2.1 foe Div 1 with code case.
If I have to comply, I will need to raise up the level nozzle but then it will not be below the low liquid level to check the liquid. We have many Div. 1 vessels and we have never concerned about the ratio as it is not code requirement.
Div 1 is simple. it calculates the size of the opening (major and minor, or at any angle),and reinforce it per UG-37, Fig UG-37, appendix 1-7 and 1-10. I remember in the old Div.1 code, there is a sketch in the appendix showing a hill-sided nozzle and calculation.
RE: Div 1, Code Case 2695
RE: Div 1, Code Case 2695
If you use 4.5, then I think that you are obligated to comply with 4.5.2.1. Maybe a bigger question is whether you can pick and choose which nozzles you use CC2695 and 4.5 and which ones you simply use UG-37? That will need a discussion with the AI.
RE: Div 1, Code Case 2695
RE: Div 1, Code Case 2695
RE: Div 1, Code Case 2695
1. I can selectively apply code case to where I want, either head or shell.
2. If I apply CC to shell, shell thickness and nozzle reinforcement must follow equations and restriction in part 4, including 4.5.2.1 for opening ratio.
3. Even if the ratio exceeds 1.5, I can not use part 5 to analysis. But why ? Can I not use FEA ?
RE: Div 1, Code Case 2695
You probably will not get a lot of benefit using CC2286 it on the shell. You'll get the most benefits on formed heads, cone to cylinder junctions, and nozzles.
If its my vessel, and I need the low type drain, I'd design the shell to Div. 1, and pick and choose the nozzles. However, the documentation on this may be more of a headache than it is worth.
RE: Div 1, Code Case 2695
RE: Div 1, Code Case 2695
You can provide a code case calculation for a shell and nozzle, and for the very same shell tier, provide a separate conventional Div 1 calculation for the shell and a second tilted nozzle. (Where both nozzles are located on the same shell tier.)
The same goes for two nozzles in a head, although the head will need to be thicker to accommodate the conventional Div 1 head calculation. This will simply result in additional reinforcement code the code case designed head and nozzle.
You would need to comply with the worst case of the two sets of rules for nozzle separation, tolerances, NDT etc.
Otherwise in my opinion 4.5.2.1 remains applicable and the code case specifically states that 4.5.2.3 is prohibited from use which in turn prohibits the use of U-2(g).
RE: Div 1, Code Case 2695
RE: Div 1, Code Case 2695
If we are being pedantic, I would say very slightly different calculated thickness that results in identical nominal thickness.
RE: Div 1, Code Case 2695
I have few nozzles which need REPAD . shell thickness is either 3/8",0.5", 5/8" or so and nozzles are 18" , 10" or so . material is with 304ss or 516-70 . When I turn on Code Case 2695 design case in Compress software for nozzle, The primary stress is lower than allowable stress without REPAD for the nozzles. I can also use lower sch for nozzle pipe . Can I just remove the REPADs (which were needed based Div.I ) by using code case 2695 ?
RE: Div 1, Code Case 2695