RTG & RMG Gantry Cranes: Definition & Difference
A gantry crane is the port equipment container terminals use to stack and retrieve containers in the yard. The two main types are the RTG (Rubber Tyred Gantry) and RMG (Rail Mounted Gantry). Both perform the same task but differ significantly in design, flexibility and infrastructure requirements.
RTG: Rubber Tyred Gantry Crane
An RTG crane moves on rubber tyres across a container yard. It is powered by diesel or electric cable reel and can be repositioned between yard blocks without major infrastructure changes.
| Specification | Typical Range |
|---|---|
| Lifting capacity | 40–65 tonnes |
| Stacking height | 1-over-5, 1-over-6 |
| Span | 6 container rows + 1 truck lane |
| Power source | Diesel, diesel-electric, electric |
| Flexibility | High, can move between blocks |
Manufacturers: Konecranes, Kalmar, ZPMC, Weihua
RMG: Rail Mounted Gantry Crane
An RMG crane runs on fixed rails embedded in the terminal pavement. It requires more infrastructure but offers higher precision and is better suited for automated operations.
| Specification | Typical Range |
|---|---|
| Lifting capacity | 40–65 tonnes |
| Stacking height | 1-over-6, 1-over-7 |
| Span | Larger than RTG, up to 11 rows |
| Power source | Electric (cable or busbar) |
| Flexibility | Low, fixed to rail track |
| Automation | Easier to automate than RTG |
Manufacturers: Konecranes, Kalmar, ZPMC, Liebherr
RTG vs RMG: Side by Side
| RTG | RMG | |
|---|---|---|
| Infrastructure needed | Minimal | Rail tracks required |
| Flexibility | High | Low |
| Precision | Good | Higher |
| Automation | Possible (ARTG) | Easier (ARMG) |
| Energy efficiency | Lower (diesel models) | Higher (electric) |
| Cost (new) | €1.5M – €3M | €2M – €4M |
| Best for | Flexible multi-purpose terminals | High-volume automated terminals |
When to Choose RTG vs RMG
Choose RTG when:
- Terminal handles varied cargo types
- Yard layout may change in future
- Budget is limited for infrastructure investment
Choose RMG when:
- High container throughput (>500k TEU/year)
- Automation is a strategic priority
- Long-term terminal investment is planned