Thermal stresses in a dissimilar weld joint

[octane]

How can we calculate thermal stresses in a dissimilar weld joint between austenitic and ferritic steel piping?

[ashfaqanwer]

You can use the following formula to calculate the thermal stresses:
stress = (E.dT.de)/2
where,
E = Modulus of elasticity (to be assumed same for both the metals)
dT = Temperature difference
de = Difference in thermal co-efficient of expansion for both the metals

[octane]

Thanks...
What should be the values taken for SS316L and A335 Gr. P11?
We have to operate these weld joints at 450 deg C.

[arcpro]

Thanks Ashfaq for the useful formula.

[ashfaqanwer]

Modulus of elasticity may be taken as 29 x 10e6 psi
Thermal co-efficients of expansion for SS316L and P11 can be taken as 8.9 x 10e-6 in/in/deg F and 8 x 10e-6 in/in/deg F