In the complex and demanding world of shipbuilding, the assembly of massive hull sections requires machinery of immense strength and precision. The shipbuilding gantry crane stands as a critical piece of equipment in shipyards, designed specifically to handle the enormous weight and dimensions of ship components. Its primary function is to lift, transport, and precisely position large ship segments—often weighing hundreds of tons—for assembly on the building dock or berth. A key operational feature is simultaneous lifting (or tandem lifting), where the upper and lower trolleys work in unison to hoist the same load, ensuring balanced and stable handling of massive, irregularly shaped sections.
Key Dimensions of a Shipbuilding Gantry Crane
When selecting a shipbuilding gantry crane, several technical specifications are paramount to ensure it meets the specific demands of your project:
Rated Lifting Capacity: The maximum safe load weight the crane is designed to lift, often exceeding several hundred tons for large shipyards.
Lifting Range/Lifting Height: The maximum vertical distance the hook can travel from the ground, crucial for stacking sections and providing sufficient clearance.
Span: The horizontal distance between the crane's rails, determining the working area coverage over the shipbuilding dock.
Gantry Clearance Height: The vertical space between the rail level and the underside of the main girder, allowing for the passage of materials and equipment beneath the crane.
Duty Class/Working Class: A classification (e.g., FEM or ISO standard) that indicates the intended intensity of use, factoring in load spectrum and number of operating cycles.
Lifting Speed: The speed at which the hoist raises or lowers a load, which can be variable for precise positioning.
Travelling Speed: The speed of the crane's long-travel (gantry movement along the dock) and cross-travel (trolley movement along the girder).
ZEHUA HEAVY MACHINE IN CHINA can customize the technical specifications of the Shipbuilding Crane for your actual needs, such as capacity, spreader, dimension, etc.
The Anatomy of a Shipbuilding Gantry Crane
A shipbuilding gantry crane is an intricate system composed of several key components working in harmony:
Gantry Structure: This is the crane's "skeleton," comprising the main girder (often a trapezoidal structure), legs, and the lower cross beam. It supports the entire weight of the crane and the load while providing the track for the trolley's transverse movement. It must possess extremely high resistance to bending and overturning. The leg design typically features an I-shaped rigid leg combined with an A-shaped flexible leg. Personnel can access the cabin and the top of the main girder via ladders or an elevator inside the rigid leg.
Lifting Mechanism: Acting as the crane's "lifting arm," this system includes the winch, wire rope, and hook block. Driven by motors, the winch winds or unwinds the wire rope to raise or lower the load. Many large cranes feature a "dual-hook" system on the trolleys, allowing for synchronized or independent operation. Furthermore, the mechanism is equipped with a rope arranging device to prevent the wire rope from jumping its grooves, ensuring safe operation.
Travel Mechanism: This system is divided into two parts:
Gantry Travel (Long Travel): Moves the entire crane along the ground rails, covering the length of the shipbuilding berth.
Trolley Travel (Cross Travel): Moves the lifting trolley along the rails on the main girder.
The coordination of these two mechanisms enables the "all-directional movement" of the load. These mechanisms are often fitted with an oblique travel correction device to automatically or manually correct any walking deviation.
Control System: The "brain" of the crane. It consists of an operator's cabin, a PLC (Programmable Logic Controller), and variable frequency drives for speed control. Operators use joysticks or buttons to set parameters, and the system precisely controls the speed and position of all mechanisms. Advanced cranes employ an intelligent control system with multi-hook联动 (linkage) and synchronous operation functions, achieving millimeter-level precision in positioning.
Safety Protection Devices: These are the "lifelines" of the operation. They include:
Load Limiters to prevent overload.
Moment Limiters to prevent overturning.
Travel Limit Switches to prevent mechanisms from over-traveling and colliding.
Anti-wind devices (like rail clamps) to secure the crane outdoors against strong winds.
An electronic anti-collision system for the gantry travel.
A fire alarm system.
A comprehensive safety monitoring system oversees all these functions.
Six Key Features of a Shipbuilding Gantry Crane
Versatile Functions: Capable of single lifts, tandem lifts, aerial flipping, and fine horizontal rotation of loads, providing flexibility for various complex lifting scenarios.
Optimized Gantry Design: Offers single or double girder types. The main girder often uses a variable-cross-section design for material efficiency, enhancing rigidity and stability.
Stable Leg Design: The rigid leg, available in a single-column style, provides robust support and stability.
Dual-Hook Lower Trolley: The lower trolley is equipped with main and auxiliary hooks, enabling multiple lifting points for enhanced flexibility.
Trolley Inter-penetration: The upper and lower trolleys can pass by each other, significantly improving operational flexibility and efficiency.
Variable Frequency Speed Control: All hoisting and travel mechanisms use variable frequency drives for smooth, precise speed adjustment, energy savings, and reduced wear.
How Does a Shipbuilding Crane Move?
Shipbuilding gantry cranes are characterized by their large capacity, wide span, and great lifting height. They are primarily used for the aerial flipping and precise joining of ship sections. They are typically equipped with upper and lower trolleys that run on their own tracks, with the lower trolley able to pass beneath the upper one. Through the coordinated operation of the hooks on the upper trolley, the main hook on the lower trolley, and the travel mechanisms of both trolleys, the crane can effortlessly perform the complex maneuver of flipping a massive ship section in mid-air.
How Does the Work of a Shipbuilding Crane Proceed? (Operation & Maintenance)
Proper operation and maintenance are crucial for safety and longevity.
Pre-Operation Check: Before work begins, inspect the following:
Rails should be straight, connection bolts tight, and the path clear of obstacles.
Mechanical structure should appear normal, with all connections secure.
Wire ropes should be in good condition, with rope clips firm.
All safety limit devices must be intact and functional.
Powering Up: After inspection, release the rail clamps before powering on. Check for electrical leaks using a test pen before entering the cabin via the dedicated ladder.
Test Run: Conduct a no-load test to confirm all mechanisms operate normally, brakes are reliable, and limit switches are effective.
Lifting Operation: Sound an alarm before starting. Lift and lower loads smoothly and evenly. Use tag lines to control swing for large items.
Safe Practices: Never move a load over people. Keep the hook at least 2 meters above the ground when traveling unloaded. Maintain a distance of 3-5 meters when two cranes operate simultaneously. Never use one crane to push another.
2. Post-Operation: After work, park the crane on the designated line, apply the rail clamps, raise the hook to its upper position (without a load), set all controllers to zero, cut the power, and lock the cabin.
About Shipbuilding Crane Price
As a direct manufacturer, ZEHUA HEAVY MACHINE IN CHINA offers natural price advantages. To provide you with the best crane and an accurate design and quotation, please inform us of your specific requirements and confirm necessary usage information. We welcome your inquiries and a visit to our factory to discuss your project.
HENAN ZEHUA HEAVY INDUSTRY EQUIPMENT CO., LTD
Email: sale@zehuacranes.com
Website: [https://www.zehuacranes.com/]
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