inammanj123
Mechanical
- Oct 11, 2013
- 103
dear All
Good evening,
I am designing a reactor as per ASME Sec.VIII. As of now I am using div 2. by PVElite.
The Design conditions are the following :
Design case : 8.1 mpag @ 427 Deg C
Regeneration case: 2.1 mpag @ 537.8 Deg C
external pressure: F.V @ 427 Deg C
Material : SA 387 11 cl.2
The PV-Elite shows this error in regeneration temperature case, and comes when i add skirt to the model.
"Maximum Temperature exceeded when computing compressive allowable"
I tired option div.1 but still error is coming. Kindly advice what is the possible way around of this. As per my discussion with others there are following suggestion:
1. If you design according to Div.2 class 1 max. temperature is 482°C (table 2A of sec II). So Div. 2 class 1 cannot be used due to regeneration case. Kindly confirm.
2. Since maximum temperature allowed is 649°C (table 2A for div.1 & table 5a for div 2 cl.2 of sec II), We have the option of using div.2 class 2 or div.1, but even in this case Limitation comes, due to regeneration temperature, on the compressive stress when you check the skirt. In this case I can:
• Use FEA: thermal analysis plus mechanical analysis.
• plus take advantage of code case or code interpretation( if any) which do not allow temperature limits applicable for longitudinal compressive stress and give some additional formulation For high temperature. Kindly confirm your approach to mitigate this limitation. Kindly specify if there is some code case in this regard
Good evening,
I am designing a reactor as per ASME Sec.VIII. As of now I am using div 2. by PVElite.
The Design conditions are the following :
Design case : 8.1 mpag @ 427 Deg C
Regeneration case: 2.1 mpag @ 537.8 Deg C
external pressure: F.V @ 427 Deg C
Material : SA 387 11 cl.2
The PV-Elite shows this error in regeneration temperature case, and comes when i add skirt to the model.
"Maximum Temperature exceeded when computing compressive allowable"
I tired option div.1 but still error is coming. Kindly advice what is the possible way around of this. As per my discussion with others there are following suggestion:
1. If you design according to Div.2 class 1 max. temperature is 482°C (table 2A of sec II). So Div. 2 class 1 cannot be used due to regeneration case. Kindly confirm.
2. Since maximum temperature allowed is 649°C (table 2A for div.1 & table 5a for div 2 cl.2 of sec II), We have the option of using div.2 class 2 or div.1, but even in this case Limitation comes, due to regeneration temperature, on the compressive stress when you check the skirt. In this case I can:
• Use FEA: thermal analysis plus mechanical analysis.
• plus take advantage of code case or code interpretation( if any) which do not allow temperature limits applicable for longitudinal compressive stress and give some additional formulation For high temperature. Kindly confirm your approach to mitigate this limitation. Kindly specify if there is some code case in this regard
