Calculate Welding Heat Input per Point

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In the welding process described, with a current of 110A and voltage of 20V, the heat energy generated is calculated at 2.2 kJ/sec. To determine the heat input into the welded joint, the power generated can be divided by the welding speed, which is 1 meter per minute. Increasing welding speed may reduce heat input and residual stresses, but it could also compromise weld penetration. The relationship between heat input and residual stress is complex, with higher arc powers potentially widening the residual stress volume. For managing residual stresses effectively, post-weld heat treatment and advanced welding techniques like power beam welding are recommended.
chandran
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In a welding process,i am welding two plates. The welding current is 110A and welding voltage is 20V. Suppose 100% of this electric energy is
converted to heat then the heat energy generated is 110x20. i.e., 2.2KJ/sec.
Suppose the length of the plate is 2 metres, How can i calculate what is the heat input into the welded joint at each point? I have one more data
that welding speed is 1metre/minute.
 
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(assuming no losses) power generated / welding speed = heat input per unit length
 
if the welder weld faster then heat will be less thereby producing a good
less,residual stress weld?
 
chandran said:
if the welder weld faster then heat will be less thereby producing a good
less,residual stress weld?
Perhaps. Any weld is going to create stresses. The increased speed would have to be balanced by the fact that a certain percentage of the weld penetration would be sacrificed. Most welds are stress relieved after the process.
 
Yeah, if you require the weld to penetrate (well, you usually do) I think you can't really gain much residual stress wise by decreasing heat input (material properties are a different matter of course). Typically heat input affects the residual stress gradient at line of fusion towards the base material, where there is a square root dependency between the yielded zone and arc power, which again has a linear relationship with the extension of the residual stress field - but this leaves the weld metal residual stresses still as is, higher arc powers widen the volume under residual stresses. Would go with post-weld heat treatment.
 
Power beam welding processes (e-beam, laser welding) tend to be better in applications where residual stress is a concern. The power density is much higher, although the net heat input is often lower than electric arc welding techniques. As a result, the heat affected zone tends to be a lot smaller. (Pretty much what Perennial said...). I don't think a simple increase of welding speed is going to solve any problems.
 
Hello, How to input heat source in welding simulation ( ANSYS ).By heat flux or heat genaration or heat flow etc...?.How to calculate if effic=60%,V=16, I=80,weld speed=1 m/min.
 
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