1. What is a Portal Crane?
1.1 Definition & Basic Function
A Portal Crane (or Gantry Crane) is a lifting machine characterized by a bridge structure supported by legs (portal legs) that run on rails or rubber tires. The "portal" design creates a passageway underneath, allowing trucks, trains or vessels to pass through — maximizing yard efficiency. It is designed for heavy outdoor material handling in ports, shipyards, steel plants and construction sites.
1.2 Main Application Areas
· Ports & Terminals – Bulk cargo (coal, ore, grain), container loading/unloading
· Shipyards – Shipbuilding, block assembly, engine installation
· Steel Mills – Scrap handling, coil lifting, slab transport
· Railway Yards – Intermodal container transfer
· Construction & Warehousing – Precast elements, heavy machinery storage
2. Types of Portal Cranes
2.1 By Structure Classification
Type |
Description |
Best For |
Full-Portal Crane |
Bridge supported by two legs running on ground rails |
Large yards, shipyards, bulk terminals |
Semi-Portal Crane |
One leg on rail, other on elevated runway |
Factory loading bays, warehouse edges |
Adjustable Height Portal Crane |
Legs can be raised/lowered for varying clearance |
Sites with different vessel/truck heights |
Portal Jib Crane |
Jib arm mounted on portal structure |
Precise positioning within wide area |
2.2 By Drive & Mobility
· Electric motor driven – Most common, eco-friendly, low noise
· Hydraulic driven – For precise positioning and heavy loads
· Rail-Mounted – Fixed path, high-frequency repetitive tasks
· Rubber-Tired Portal Crane – Flexible movement, multi-purpose yards
3. Core Technical Parameters
Parameter |
Typical Range |
Selection Consideration |
Lifting Capacity |
5 t – 200 t |
Heaviest single load + attachments (grab/magnet) |
Span (Rail to Rail) |
10 m – 60 m |
Width of working area, number of lanes |
Lifting Height |
8 m – 35 m |
Clearance for tallest vessel/truck |
Outreach (Cantilever) |
5 m – 25 m |
How far beyond rails you need to reach |
Hoisting Speed |
5 – 40 m/min |
Desired cycle time |
Working Class |
A5 – A8 (FEM/ISO) |
Operating frequency and intensity |
Wheel Load |
Varies |
Critical for existing rail/foundation design |
4. How to Choose the Right Portal Crane
4.1 Bulk Cargo Terminal (Coal, Ore, Grain)
Recommended: Capacity 25–50 t with grab, span 25–45 m, outreach 10–15 m both sides, anti-sway, high-speed hoist, working class A7/A8.
4.2 Shipyard (Shipbuilding)
Recommended: 100–200 t (tandem optional), span 40–80 m, lifting height 25–35 m, VFD fine positioning, dual hoist, class A6.
4.3 Steel Mill / Scrap Yard
Recommended: 20–40 t with magnet/grab, heat-resistant components, dust-proof electrics, reinforced structure, class A7.
4.4 Railway Container Transfer
Recommended: 40.5–50 t, span 25–35 m (cover multiple tracks), spreader with twist locks, semi-automation, class A6–A7.
5. Portal Crane Design & Environmental Adaptations
5.1 Structural Features
· Main Girder: Box girder (high rigidity) or truss (light weight, wind pass-through)
· Legs: A-frame or U-shape, optional adjustable height
· Rails: P43/P50/QU70 matched to wheel load
· End Carriages with anti-derailment devices
5.2 Safety Systems
· Load Moment Indicator (LMI) – real-time capacity monitoring
· Anti-collision system for multiple cranes on same runway
· Wind speed anemometer + rail clamps for storm protection
· Bumpers, end stops, multi-point emergency stop
5.3 Environmental Protection
· Coastal/Port: C5-M paint, stainless steel fasteners, IP56 electrics
· Dusty (steel mills): Sealed cabins, pressurized control rooms
· Cold climates: Low-temp steel, heated cabins, cold-resistant cables
· Hot climates: Cabin ventilation, heat shields
6. Operation & Maintenance Guidelines
6.1 Daily Operator Checks
· Visual inspection of structure, wire ropes, hooks; test limit switches and brakes; check travel rails for obstacles.
6.2 Periodic Maintenance Schedule
Interval |
Maintenance Task |
Remarks |
Weekly |
Bolt tightening (critical joints) |
Rail clamps, leg-to-girder connections |
Monthly |
Gearbox oil level & condition |
Check for contamination |
Quarterly |
Wire rope lubrication & inspection |
Log broken wires |
Semi-Annually |
Brake pad wear measurement |
Replace if below threshold |
Annually |
Load testing (100% – 125% SWL) |
Certify by third party |
Every 5 Years |
Full NDT of critical welds |
Ultrasonic / MPI testing |
7. Portal Crane vs. Similar Equipment
Feature |
Portal Crane |
RTG Crane |
Overhead Crane |
Support |
Legs on ground rails |
Rubber tires |
Building structure |
Typical Span |
10 m – 60 m |
18 m – 30 m |
Up to 40 m |
Outdoor use |
Yes (weatherproof) |
Yes |
No (indoors) |
Under clearance |
High (vehicles pass) |
High |
Limited |
Best Application |
Bulk handling, shipyards |
Container yards |
Factory workshops |
8. Why Choose HENAN YUNTIAN Portal Cranes?
· 20 years experience – 4,500+ employees, 430 global branches, 200+ senior engineers
· International certifications – CE, ISO, SGS, TUV, BV, EAC, and class societies (CCS/ABS/DNV/LR)
· Customization – Any capacity, span, outreach, control (remote, semi-auto, full auto)
· Project highlight: Turkey steel mill – 4 portal cranes (32 t, 28 m span) for scrap handling, magnets+grabs interchangeable, 99% uptime over 3 years
HENAN YUNTIAN CRANE CO., LTD.
sales@sgycranes.com
+86-373-3055523
https://yuntiancrane.com
