Impact test results : SA20 vs UG84

[jaguar69]

Hi,
I would like to get explanation regarding the following.
I have a pressure vessel in SA537 Class 2, wall thk = 60mm (2 23/64"), MDMT=-50°C (-58°F).
I shall perform impact tests (specific request from client) and I'm wondering what will be the minimum valeur on those tests.
According to SA20, table A2-15 the average acceptable value is 27J, but according to ASME VIII, Div 1, UG84, the average acceptable value is 42J
Somebody could explain please which is the correct minimum value and why I find difference between SA20 and UG84.

Thank by advance

 

[metengr]

The impact energy value will be based on the requirement in the code of construction (ASME Section VIII, Div 1). The material specification values are minimum and used generally unless the code of construction provides specific requirements, which take precedence over specification requirements.

With that said, look at Figure UG-84.1 of ASME Section VIII, Div 1, for the specified minimum YS of SA 537 Class 2, the minimum CVN value is 20 ft-lbs or higher based on thickness and MDMT.

 

[jaguar69]

Hi metengr

it's more clear now. thank a lot

 

[Guest102023]

In general, the more stringent of all applicable codes and standards will apply. So-called construction codes may add or increase certain materials and testing requirements.

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"