Structural analysis of an assembly frame with a deviating material.

We have an industrial welded steel frame that supports a 650 kg power converter hung from several mounting points. Operators work beneath it, and the frame is moved on castors under full load. The original S235J0 UPN 100 channels (100 × 50 × 6 mm) are being replaced with ASTM A36 formed channels (4 × 2 × 0.25 in), and we need to confirm the frame is safe for its intended use.

Scope:
- Material and section evaluation: comparison of the original and replacement channels, covering mechanical properties and section properties
-FEA: a shell model of the full frame built from our STEP files, run for both the original and the A36 frame so the effect of the change is shown side by side
-Load cases: frame standing still; unequal load and uneven floor (one castor unloaded); starts, stops and acceleration; floor joints and thresholds. We agree the loading factors with you before you run them.
-Stability: frame stability, buckling and tipping
-Connections and castors: welds, gussets, mounting brackets, castor load against the manufacturer’s rating, and the castor bolts and mounting plates
-Design verification: pass/fail against EN 1993, deflection check, and recommended changes for anything that fails
- Report: a clear technical report