Single- and double-girder overhead cranes should not be selected by rated capacity alone. Span, lift height, hook approach, duty, speeds, attachments, load spectrum, building clearances and future process changes all affect the decision.
A single-girder arrangement may reduce bridge self-weight and building loads where the application is suitable. A double-girder arrangement may provide advantages for long spans, higher duty, service platforms, special trolleys or improved upper hook approach. These are project-dependent advantages, not universal rules.
The comparison should include wheel loads, runway capacity, deflection criteria, maintenance access, installation constraints and lifecycle cost. Final selection requires verified building and operating data.
This content supports preliminary review. Equipment selection, structural calculations, compliance and commissioning decisions must be verified using site data and competent engineering.
