45 deg lateral vs 90 deg branch - which has higher sif ?

FEA using NozzlePro & FESIF shows 45 deg lateral branch is having lower SIF than 90 deg branch.

Many US design firms consider 45 deg branch SIF as 1.5 times 90 deg branch SIF; CODETI takes 1.68 times.

Now, 45 deg branch is non-code item - we need to depend on FEA; is CODETI or US design firms wrong or FEA results wrong ?

reg,
sam

What kind of branches have you analyzed? Direct Connection Set-On type?

One idea is that the 45° branches have more area on the main pipe i.e. the cutting on the main pipe is more than 90° branches. So the SIF should be higher in case of the 45°. The other group says that this type of branches have less SIF (reason may be FEA result) and another group says that this type of branch is normally given on the flare lines which do not encounter so much cycles of use and concept of SIF is attached with the cyclic loads.
Anyhow let's wait for stress gurus on this forum to answer your query.

See the link below:
Chuck Becht's post and opinion is important.
http://65.57.255.42/ubbthreads/ubbthreads.php?ubb=showflat&Number=3902