We performed a failure analysis and subsequent design modifications on a 1,400 ton hydraulic press frame that had experienced cracks in high stress critical locations. Structural life of components are often limited by weld geometry, lack of pre-heating, and lack of post-weld heat treating. For the press, the geometry of the repair welds created a constrained weld joint.
In addition, the residual stresses created from the solidification of the liquid weld pool would be expected to exceed the minimum strength of the material. This condition reduces the crack initiation and fatigue life endurance of the weld repair. Post weld heat treating reduces the residual tensile stresses to approximately 25% of the yield strength of the material.
We also performed a fatigue analysis on the press frame to determine the stresses and fatigue life under operational loads. It was concluded that the press in its current condition had a limited fatigue life. We then designed and analyzed a new frame for a 2,000 ton capability using higher strength steel.
OCE Performs Design, Analysis and Troubleshooting Services for Clients in Industries including Energy, Petrochemical and Manufacturing.