AlexTetra
Industrial
- Jun 13, 2015
- 1
Hello,
I am writing on my master thesis and got a tough problem I cant find the answer for.
I need to do an FEA simulation of the stresses in a tube to header weld (weld toe). For that, I need to use the notch stress approach. The problem is, that most of the recommendations are for the off shore industry for a wall thickness > 5mm, to model the edge of the toe with a radius of 1mm. The HP tube to header joint I am trying to analyse has a WT of around 3.5mm and thats where the problem starts. Other recommendations recommend if the WT is below 5mm to model the notch with a radius of 0.05mm, which leads to an SCF of around 10 in the weld toe, which seems to be a bit high for a simple axial (tensile) load.
So I am stuck and dont know how to validate the results. Everything I can find are calculations for the offshore industry for way bigger tubes and tubular joints, but there is nothing in detail for a boiler.
If I go with the 1mm notch radius, I get an SCF of around 3.5, which seems a bit more reasonable...but how to argue/validate those results?
Maybe some of you got some experience in that area. Would be glad if someone can give me a few tips.
thanks in advance.
I am writing on my master thesis and got a tough problem I cant find the answer for.
I need to do an FEA simulation of the stresses in a tube to header weld (weld toe). For that, I need to use the notch stress approach. The problem is, that most of the recommendations are for the off shore industry for a wall thickness > 5mm, to model the edge of the toe with a radius of 1mm. The HP tube to header joint I am trying to analyse has a WT of around 3.5mm and thats where the problem starts. Other recommendations recommend if the WT is below 5mm to model the notch with a radius of 0.05mm, which leads to an SCF of around 10 in the weld toe, which seems to be a bit high for a simple axial (tensile) load.
So I am stuck and dont know how to validate the results. Everything I can find are calculations for the offshore industry for way bigger tubes and tubular joints, but there is nothing in detail for a boiler.
If I go with the 1mm notch radius, I get an SCF of around 3.5, which seems a bit more reasonable...but how to argue/validate those results?
Maybe some of you got some experience in that area. Would be glad if someone can give me a few tips.
thanks in advance.