APMT operates ten Noell machinery-on-trolley cranes at their Pier 400 terminal in Los Angeles. The original trolley structure was torsionally rigid. Some of the diagonal members cracked due to warping caused when one wheel is out-of-plane to the other three. Liftech provided design modifications to reduce the stresses in the members due to warping.
The trolley modifications involved replacing the diagonals with a link system in the waterside wall of the trolley. The modified trolley structure is torsionally flexible.
Los Angeles, California, USA