22/07/2026
How to select the right overhead crane? A no-BS framework.
Most buyers only ask: "What tonnage?" and "How much?" — that's how you end up with the wrong crane.
Here's the real selection logic. No sales pitch. Just engineering.
🔹 Step 1: Lifting Capacity (Tonnage)
Capacity = net load (exclude hook and spreader).
Always add 10-15% margin. If your max load is 10T, spec for 12.5T. The cost difference is small; regret is big.
🔹 Step 2: Span (rail center-to-center)
This is NOT the workshop width.
Measure the actual rail layout. Every extra 1m of span increases girder bending — more steel, more cost. Don't guess.
🔹 Step 3: Duty Class (most people get this wrong)
It's not about capacity. It's about how often and how heavily you use it.
Quick guide:
- A3 (FEM 1Am) – occasional use, maintenance shops
- A4 (FEM 1m) – assembly lines, warehouses
- A5 (FEM 2m) – machine shops, general production
- A6 (FEM 3m) – heavy production, foundries
- A7-A8 (FEM 4m) – continuous heavy service, steel mills
Don't over-spec (wasting money) or under-spec (early fatigue). Be honest about your actual usage.
🔹 Step 4: Single-Girder vs. Double-Girder
Single-girder: 1-20T, span up to ~30m, lower cost, lower building height, less torsional rigidity.
Double-girder: 5-500T+, any span, higher cost, higher building height, much more rigid and precise.
Choose single if you're cost-sensitive with light-to-moderate duty. Choose double for heavy loads, large spans, or precise positioning.
