What are the different types of RTG cranes?

RTGs (Rubber-Tyred Gantry Cranes) are classified across five core dimensions: main girder structure, leg frame configuration, power system, degree of automation, and operational function. They are utilized in various settings, including ports, container yards, and precast concrete plants. The following outlines the mainstream types and key selection criteria:

I. Classification by Main Girder Structure (The Most Intuitive Classification)
1. Single-Girder RTG
Structure: Features a single box-girder main beam, supported by legs and rubber tires.
Load Capacity: 1–35 tons (Light to Medium Duty).
Span: ≤ 20 meters.
Features: Lightweight, low cost, low energy consumption, simple maintenance, and strong site adaptability.
Applications: Small container yards, warehouses, precast concrete plants, and the transfer of lightweight containers or structural components.2. Double-Girder RTG (The Mainstream Choice in Ports)
Structure: Features twin main girders with rigid connections, providing high overall structural rigidity.
Load Capacity: 35–70 tons (Heavy Duty).
Span: 23–40 meters (Suitable for handling multiple rows of containers).
Features: Excellent stability, strong wind resistance, high stacking capability (6–10 tiers), and suitable for high-frequency, heavy-duty operations.
Applications: Large port container terminals, and the transfer of heavy precast concrete elements or steel structures.
II. Classification by Leg Frame Structure (Key to Site Adaptability)
1. A-Frame RTG (Most Commonly Used)
Structure: The support legs form an "A" shape—narrower at the top and wider at the bottom—with a flared base.
Features: Excellent stability and wind resistance; mature manufacturing processes; moderate cost.
Limitations: Limited clearance at the base, resulting in slightly lower efficiency for gantry travel (longitudinal movement).
Applications: Standard port container yards, inland container depots, and precast concrete plants.
2. U-Frame RTG
Structure: Features vertical support legs with a "U"-shaped opening at the base.
Features: Provides ample clearance at the base, facilitating the rapid passage of container trucks and trailers.
Limitations: Requires high manufacturing standards; slightly higher cost; wind resistance is slightly inferior to that of the A-frame type. Type
**Applicability:** Rapid cargo handling zones in ports, multi-lane container yards, and scenarios requiring frequent vehicle transit.
**III. By Power System (Focus: Environmental Impact & Operating Costs)**
**1. Diesel Generator Set (Traditional RTG)**
**Power Source:** Diesel engine + Generator; fully electric drive system.
**Features:** Independent power supply, unrestricted by power grid availability, flexible relocation capabilities.
**Limitations:** High fuel consumption, high emissions, high noise levels, high maintenance costs.
**Applicability:** Locations without grid access, remote container yards, temporary operation sites.
**2. Hybrid RTG (Mainstream Energy-Saving Solution)**
**Power Source:** Diesel + Battery / Supercapacitor; features regenerative braking energy recovery.
**Features:** 30%–50% reduction in fuel consumption, low emissions, low noise levels, extended operating range.
**Applicability:** Modern ports with strict environmental regulations and high-intensity operations.
**3. Fully Electric RTG (Zero Emissions)**
**Power Source:** External grid connection / Conductor rails / Lithium-ion batteries.
**Features:** Zero emissions, low noise, low energy consumption, minimal maintenance requirements, low operating costs.
**Limitations:** Requires grid access or charging infrastructure; slightly lower operational flexibility.
**Applicability:** "Green" ports, container yards with fixed travel routes, environmentally controlled zones.
**4. Diesel-Hydraulic Drive RTG**
**Power Source:** Diesel engine + Hydraulic pump; hydraulic drive for travel and hoisting functions.
**Features:** Compact structure, rapid response times, high torque output.
**Applicability:** Small-scale RTGs, specialized operating conditions, scenarios with strict space constraints.
**IV. By Degree of Automation (Direction of Efficiency Upgrades)**
**1. Manual RTG (Basic Model)**
**Operation:** Manual control from the operator cabin; manual positioning, hoisting, and travel.
**Features:** Low initial cost, flexible operation, requires highly skilled operators.
**Applicability:** Small container yards, low-volume operations, scenarios with limited budgets.
**2. Semi-Automated RTG (Mainstream Model)**
**Configuration:** Automatic positioning, anti-sway control, automatic skew correction, remote monitoring capabilities.
**Features:** Enhanced efficiency, reduced physical workload for operators, precise positioning accuracy.
**Applicability:** Medium-sized ports, standardized container yards.
**3. Fully Automated RTG (ARTG – High-End Model)**
**Configuration:** Unmanned operation, automatic path planning, automated stacking and retrieval, centralized remote control.
**Features:** 24/7 operation capabilities... Continuous operation, high efficiency, safe and reliable, extremely low labor costs
Applications: Large-scale automated terminals, high-density intelligent container yards
V. By Operational Function (Specialized Scenarios)
1. Standard Container RTG
Configuration: Dedicated telescopic spreader (20/40/45 ft), anti-sway system
Load Capacity: 35–41 tons (standard containers), 70 tons (heavy-duty containers)
Applications: Port container stacking, loading/unloading, and transshipment
2. Specialized RTG for Precast Components
Configuration: Customized spreader (lifting beam/clamp), anti-slip platform, low center-of-gravity design
Features: Adaptable to extra-long/extra-wide precast components (box girders, tunnel segments, wall panels)
Applications: Precast component factories, bridge prefabrication yards
3. Straddle Carrier-style RTG
Structure: Integrated frame design; straddles cargo directly during operation
Features: Combines lifting, transshipment, and stacking functions; requires no auxiliary equipment
Applications: Short-distance container transshipment, connection between quay apron and container yard
Quick Selection Guide (By Scenario)
Small Yards / Precast Factories → Single-girder A-frame + Diesel / Lithium-battery power
Standard Port Yards → Double-girder A-frame + Hybrid / Fully Electric power
Rapid Handling Zones → Double-girder U-frame + Fully Electric / Semi-automated operation
Intelligent Automated Terminals → Double-girder A-frame + Fully Electric + Fully Automated (ARTG)
Off-grid / Temporary Sites → Single/Double-girder + Diesel Generator Set