Weld Stress
Weld Stress
(OP)
Hello all, I am trying to analyze the stress in an attachment weld in order to determine the minimum allowable fillet weld leg length (w) by using the following formula:
w = f/fw
where f = actual force [lbs]
fw = maximum allowable unit force on an equal-leg
fillet weld equal to 1" [lbs/linear inch]
= .707*E*Sa
E = joint efficiency based on throat area
Sa = maximum allowable stress of the base metal
I am trying to find the correct value for the allowable stress of a weld (Sa). I am using E70XX electrodes and welding A36 structural steel I beams and angles to a SA-516-70 presure vessel shell.
My questions are as follows:
1) is the value of Sa = 21,000 psi
2) is it correct to assume an E of 1.0?
I have also seen the formula for fw written as follows:
fw = .707*w T
where fw = allowable force on the fillet weld, 1" long
w = leg size of fillet weld
T = allowable shear stress on throat of weld
any comments?
w = f/fw
where f = actual force [lbs]
fw = maximum allowable unit force on an equal-leg
fillet weld equal to 1" [lbs/linear inch]
= .707*E*Sa
E = joint efficiency based on throat area
Sa = maximum allowable stress of the base metal
I am trying to find the correct value for the allowable stress of a weld (Sa). I am using E70XX electrodes and welding A36 structural steel I beams and angles to a SA-516-70 presure vessel shell.
My questions are as follows:
1) is the value of Sa = 21,000 psi
2) is it correct to assume an E of 1.0?
I have also seen the formula for fw written as follows:
fw = .707*w T
where fw = allowable force on the fillet weld, 1" long
w = leg size of fillet weld
T = allowable shear stress on throat of weld
any comments?
RE: Weld Stress
The joint efficiency (E) used in calculation for seamless shells is 1. For weld joints subject to tension the values depend on the type of weld and testing processes. The efficiency can vary from .45 to 1.
Hope this helps.
J.Roth
RE: Weld Stress