Welding Torsion Resistace
Welding Torsion Resistace
(OP)
I have a design, which uses 7/16 fillet welds to weld a tube to a pipe (Centerline of the tube is perpendicaular to the centerline of the pipe). The welding length is about Lw= 57*2= 114in and Fexx =70ksi
90k-ft torsion needes to be transfered.
I calculated like this:
Tn = 0.6* Fexx * (7/16* 0.707) *Lw *(7/16") /12
and Tn/2 only gives me 27 kips-ft
Something is wrong with the calculation. Can anybody help? Thank you very much.
90k-ft torsion needes to be transfered.
I calculated like this:
Tn = 0.6* Fexx * (7/16* 0.707) *Lw *(7/16") /12
and Tn/2 only gives me 27 kips-ft
Something is wrong with the calculation. Can anybody help? Thank you very much.





RE: Welding Torsion Resistace
what size tube? what size pipe? is the weld all around? if so is it square or circular?
RE: Welding Torsion Resistace
and Tn/2 only gives me 27 kips-ft
It seems to me you are calcing the k/in strength of the weld and applying a 7/16" moment arm to the weld. I don't where that is coming from, but it doesn't sound right. You should be using the Ip for the weld group.
Please explain in more detail the weld group.
RE: Welding Torsion Resistace
If your asking about a square rectangle tube I'd just use the standard J values for those [J=((short length*long length)^3)/6 and making sure to use the actual (increased for the curve) length of the weld that is perpendicular to the pipe.
Hope that helps,
John
RE: Welding Torsion Resistace
Have alook at this site:-
http://www.gowelding.com/calcs/
regards
desertfox