Problem as follows;
We have a large cast component which is the main part of a structural frame of a hydraulic press type machine. In service loads are high cyclic tensile, clamp unclamp etc.
To save on cost & lead time it is advised that we produce the part from welded plates. Stress relief, weld inspection (ultrasonic)& process control are all advised.
My main concern with the part is the level of welding. The majority of welds are partial penetration welds. Most plates are about 50mm thick. We feel that this will greatly weaken the structure as compared to our existing cast base.
Such welds we feel should also show up as elevated stresses on a completed FEA as the bonded metal to metal contact area is greatly reduced. In the FEA, Welding was simulated by merging the nodes along the entire interface surface of the plates.
Does this accurately reflect the proposed level of partial welding?
Should the nodes be merged only along the welded interface and not the entire interface area as seems to be the case.
I have raised this issue with the FEA guys but they say it is fine. Surely when you reduce the bonded area at the plate interfaces there is a large reduction in strength.
Appreciate any comments.
Speedy.
We have a large cast component which is the main part of a structural frame of a hydraulic press type machine. In service loads are high cyclic tensile, clamp unclamp etc.
To save on cost & lead time it is advised that we produce the part from welded plates. Stress relief, weld inspection (ultrasonic)& process control are all advised.
My main concern with the part is the level of welding. The majority of welds are partial penetration welds. Most plates are about 50mm thick. We feel that this will greatly weaken the structure as compared to our existing cast base.
Such welds we feel should also show up as elevated stresses on a completed FEA as the bonded metal to metal contact area is greatly reduced. In the FEA, Welding was simulated by merging the nodes along the entire interface surface of the plates.
Does this accurately reflect the proposed level of partial welding?
Should the nodes be merged only along the welded interface and not the entire interface area as seems to be the case.
I have raised this issue with the FEA guys but they say it is fine. Surely when you reduce the bonded area at the plate interfaces there is a large reduction in strength.
Appreciate any comments.
Speedy.