MZ Type Grab Double Girder Gantry Crane

 

Key Features:

Double Girder Structure – Provides higher lifting capacity and better stability compared to single girder designs.

Grab Bucket Mechanism – Equipped with a motorized grab bucket (clamshell or orange peel type) for efficient loading/unloading of loose materials.

Gantry Design – Runs on rails or wheels, allowing movement along a fixed track for large-area coverage.

High Efficiency – Suitable for continuous operation in heavy-duty environments.

Customizable Span & Lifting Capacity – Can be designed for different spans (usually 10–35m) and lifting capacities (typically 5–50 tons or more).

 

Comparison with Other Cranes

Feature	MZ Grab Gantry Crane	Single Girder Gantry Crane	Overhead Crane
Lifting Capacity	High (5–50+ tons)	Medium (1–20 tons)	Medium (1–32 tons)
Span	Long (10–35m+)	Short to medium (5–25m)	Limited by building
Material Handling	Bulk (grab bucket)	Single loads (hook)	Single loads
Mobility	Rail-based, outdoor/indoor	Rail/wheel-based	Fixed runway
Automation	Yes (common)	Limited	Possible

 

Warranty :1 Year

Weight (KG):35000 kg

Feature:Gantry Crane

Application:Railway Station/Sea Port/Yard/Subway

Rated Lifting Moment:Different

Material: Q235/Q345

Working Temperature:-40~40 ℃

Legs space:Bigger than normal

Control:Cabin control

Electrical parts:Schneider

Power Source:380~480V, 50hz/60hz

Power supply:M5~M8 (ISO)

Main electrical parts:Schneider Brand

Crane feature:High Efficiency

 

1. Double Girders

 

Two parallel box-type girders that form the primary horizontal structure. Offer strong load-bearing capacity and stability.

2. Gantry Legs (Support Frame

A-shaped or straight-leg columns that support the girders and transfer loads to the ground via wheels.

 

 

3. Grab Trolley (Hoisting Trolley)

Travels along the girders; includes the hoist mechanism and the grab bucket system for lifting and dumping materials.
4. Grab Bucket

Mechanical or hydraulic four-rope grab designed to lift bulk materials like sand, coal, or scrap. Operates with opening and closing mechanism.

 

5. Hoisting Mechanism

Motorized winches with wire ropes; provides vertical lifting power for the grab. Dual winches often control opening/closing and lifting separately.
6. Crane Travel Mechanism

Drives the entire crane along rails laid on the ground. Includes motors, wheels, brakes, and drive shafts.

7. Electrical System

Includes control panel, inverter (VFD), wiring, safety interlocks, and power supply system (cable drum or festoon system).
8. Operator Cabin

Usually located on the trolley for a better view of the grab. Includes joysticks, monitors, and safety devices.

9. Limit Switches & Sensors

Prevent over-travel and over-lifting; enhance safety and automation.
10. Rail Clamps / Windproof Anchors

For outdoor use, these prevent crane movement during high winds or storms.

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11. Buffers and End Stops

Installed at both ends of travel routes to absorb impact and prevent collisions.

Optional Components:

Anti-sway system

Remote control system

Load monitoring & data logger

Emergency stop system

Environment protection devices (dust-proof, rainproof)

SKETCH

Main technical

 

High Efficiency in Bulk Material Handling

The grab bucket allows quick loading/unloading of loose materials (coal, ore, grain, etc.), significantly improving productivity compared to manual or excavator-based methods.

Double Girder Strength & Stability

Offers higher lifting capacity (typically 5–50+ tons) and longer spans (10–35m+) than single girder designs.

Better resistance to bending and torsional forces, ensuring smooth operation under heavy loads.

Versatile Grab Bucket Options

Supports clamshell, orange peel, or motorized grabs for different materials (e.g., coal, sand, scrap metal).

Can handle both dry and wet bulk materials effectively.

Wide Coverage & Mobility

Runs on rails, enabling longitudinal travel for large storage yards, ports, or construction sites.

Can be designed for indoor or outdoor use (with weatherproofing features).

Precision Control & Automation

Equipped with variable speed drives for smooth operation.

Can integrate remote control, PLC automation, or weighing systems for optimized material management.

Durability & Low Maintenance

Robust steel construction with wear-resistant components (e.g., high-grade wire ropes, reinforced grabs).

Designed for 24/7 operation in harsh environments (ports, steel plants, power stations).

Safety Features

Includes overload protection, limit switches, anti-collision systems, and emergency brakes.

Optional windproof anchors for outdoor use in windy conditions.

 

1. Ports & Terminals

Loading/unloading ships, barges, and trucks with bulk cargo (coal, grain, fertilizers).

Stockpiling and reclaiming materials in storage yards.

2. Power Plants

Handling coal, lignite, and ash in thermal power stations.

Transporting fly ash and slag for disposal/recycling.

3. Steel & Metallurgical Plants

Moving iron ore, scrap metal, limestone, and coke.

Charging raw materials into furnaces or handling finished products.

4. Mining & Quarries

Transporting gravel, sand, crushed stone, and minerals.

Loading trucks or conveyor systems for further processing.

5. Construction & Cement Industry

Handling cement, clinker, and aggregates in bulk.

Assisting in large-scale infrastructure projects (dams, bridges).

6. Grain & Food Processing

Moving wheat, rice, soybeans, and other grains in silos or storage facilities.

Can be fitted with dust-proof grabs for food-grade safety.

7. Waste Management & Recycling

Handling scrap metal, municipal waste, and recyclables.

Used in landfills and recycling centers for bulk material transfer.

 

 

1. Design and Planning

Demand Analysis: According to customer needs and usage scenarios, a detailed demand analysis is carried out to determine the specifications, load, span, lifting height, etc. of the crane.

Engineering Design: Engineers use CAD and other design software to carry out detailed design, including structural, mechanical, electrical and other aspects to ensure that the design meets relevant standards and specifications.

2. Material Procurement

Material Selection: Select appropriate steel, motors, control systems and other components according to design requirements.

Supplier Screening: Screen suppliers of materials and components to ensure the quality and reliability of materials.

3. Processing and Manufacturing

Cutting and Forming: Cut, weld, bend and other processes on steel to form main beams, end beams and other structural components.

Machining: Precision machining of key components, such as turning, milling, drilling, etc., to ensure that the size and accuracy meet the design requirements.

Surface Treatment: Spray, galvanize or rust-proof metal parts to enhance corrosion resistance and aesthetics.

4. Assembly

Component Assembly: Assemble the main beam, end beam, trolley, lifting mechanism and other components to form a complete crane structure.

Installation of electrical system: Install electrical equipment such as motors, control cabinets, sensors, limit switches, etc. to ensure the normal operation of the electrical system.

5. Debugging and testing

Preliminary debugging: Carry out preliminary debugging of the crane to check the coordination and operation of each component.

Load test: Carry out load test to ensure the safety and stability of the crane under rated load, and test the functions of safety devices such as overload protection and limit switches.

Performance test: Test the performance indicators of the crane such as lifting speed, running speed, braking effect, etc. to ensure that they meet the design requirements.

6. Quality inspection

Quality inspection: Carry out a comprehensive quality inspection of the crane, including appearance, size, performance, etc., to ensure compliance with relevant standards.

Safety assessment: Carry out safety assessment to ensure the normal operation of all safety devices and systems.

7. Delivery and installation

Packaging and transportation: Pack qualified cranes and prepare them for transportation to the customer site.

On-site installation: Carry out on-site installation according to customer requirements, including basic production and equipment debugging.

Training and handover: Train operators to ensure that they master the operation methods and safety precautions of the equipment and complete the handover work.

 

 

 

 

 

 

 

Material Inspection

Quality Inspection: Strict quality inspection is carried out on the purchased raw materials to ensure that they meet the design requirements and national standards.

Material Storage: Qualified materials are stored according to classification to prevent corrosion or damage.

Cutting and Forming

Steel Cutting: Use plasma cutting, laser cutting or flame cutting and other technologies to cut the steel according to the size of the design drawing.

Forming Processing: Form the steel plate through bending, rolling, welding and other processes to manufacture the main beam, end beam and other structural parts.

Welding

Component Welding: The cut and formed steel parts are welded into the main structures such as the main beam, end beam and trolley. The welding process needs to be strictly controlled to ensure the structural strength and welding quality.

Weld Inspection: Use non-destructive testing technology (such as ultrasonic testing, radiographic testing) to inspect the welds to ensure that there are no cracks or other defects.

Machining

Precision Machining: Precision machining is performed on the key components of the crane, such as wheel sets, bearing seats, pulleys, etc., to ensure their dimensional accuracy and surface quality.

Assembly of the whole machine

General assembly: On the basis of pre-assembly, the overall assembly of the crane is carried out, including the final installation of the main beam, end beam, lifting mechanism, walking mechanism, etc.

Commissioning and testing

Under dynamic conditions, the operating performance of the crane is tested, including the testing of lifting, walking, steering and other functions. The overall size of the assembled bridge crane is checked to ensure that all dimensions meet the design requirements.

Spraying and anti-corrosion treatment

Surface treatment Rust removal: Rust removal on the surface of the crane, common methods include sandblasting, pickling, etc. Primer spraying: Spray anti-corrosion primer on the treated surface to prevent metal oxidation and corrosion. Topcoat spraying Color spraying: Spray topcoat according to customer requirements or industry standards to give the crane a protective and decorative effect. Marking: After spraying, mark the crane's identification information in accordance with the specifications, such as model, rated load, etc.

Factory and installation

Packaging and transportation

Packaging protection: Protectively package the key components of the crane to prevent damage during transportation. Transportation arrangement: According to the equipment size and transportation conditions, select a suitable transportation method to transport the crane to the customer's site.

Acceptance and delivery

Customer acceptance

On-site acceptance: The customer conducts on-site acceptance of the crane according to the contract requirements and technical specifications to check the performance and quality of the equipment.

Problem rectification: If any problems are found, the manufacturer needs to rectify them in time to ensure that the equipment fully meets the customer's requirements. Delivery and use Operation training: The manufacturer usually trains the customer's operators to ensure that they can operate the crane correctly and safely.

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