Overhead Grab Crane

Types of Overhead Grab Cranes

A. Based on Grab Bucket Design

Type	Description	Best For
Clamshell Grab	Two hinged buckets that open & close like a shell	Grain, sand, coal, fertilizers
Orange Peel Grab	Multiple (4-6) hinged jaws for gripping scrap	Scrap metal, demolition waste, rocks
Electro-Hydraulic Grab	Powered by hydraulic cylinders for heavy-duty use	Mining, large-scale bulk handling
Rope-Operated Grab	Uses wire ropes to open/close the bucket	Cement, fly ash, dry bulk materials

B. Based on Crane Structure

Single Girder Grab Crane – Light to medium-duty (up to 20 tons).

Double Girder Grab Crane – Heavy-duty (up to 50+ tons), longer spans.

Gantry Grab Crane – Mobile version for outdoor use (ports, stockyards).

 

Grab Crane vs. Standard Hook Crane

Feature	Grab Crane	Standard Hook Crane
Load Type	Bulk materials (loose, granular)	Solid loads (machinery, crates)
Handling Method	Scooping & dumping	Lifting & placing
Control Complexity	Requires extra ropes/hydraulics	Simpler hook operation
Common Industries	Mining, ports, steel mills	Manufacturing, warehouses

 

Core Components：Bearing, Gearbox, Motor, Pump

Place of Origin：Henan, China

Warranty：1 Year

Weight (KG)：2000 kg

Video outgoing-inspection：Provided

Machinery Test Report：Provided

Design：Double beam

Effectiveness：high efficiency

Operating speed：High speed operation

Stability：Anti-swing function

Color：Optional

Power Source：110V/220V/230V/380V/440V,customized

Span：7.5-31.5m

An overhead grab crane consists of specialized parts designed for efficient bulk material handling. Below is a detailed breakdown of its components:

 

1. Main Structural Components

A. Bridge Girders

Single or double girder construction (double girder for heavy-duty use).

Made of welded steel box sections for high strength and minimal deflection.

Supports the trolley, hoist, and grab mechanism.

 

 

B. End Trucks (End Carriages)

Wheeled frames that move along the runway rails.

Equipped with drive motors, brakes, and buffers for smooth travel.

C. Runway System

Includes rails, support beams, and columns.

Designed to withstand dynamic loads during grab operation.

2. Grab Bucket & Lifting Mechanism

A. Grab Bucket Types

Type	Description	Best For
Clamshell Grab	Two hinged buckets (rope or motor-operated)	Coal, grain, sand
Orange Peel Grab	4-6 jaws for uneven/scrap materials	Scrap metal, rocks
Electro-Hydraulic Grab	Hydraulic-powered, high precision	Heavy-duty mining

 

B. Hoist & Trolley

Main Hoist – Lifts/lowers the grab bucket.

Auxiliary Hoist – Controls grab opening/closing (for rope-operated grabs).

Trolley Frame – Moves horizontally along the bridge girders.

3. Power & Control System

A. Electrical Components

Motors (hoist, trolley, bridge travel).

Festoon or cable reel system – Manages power supply to moving parts.

Control Panel – Houses relays, contactors, and overload protection.

B. Operator Controls

Pendant Control (wired handheld).

Radio Remote Control (wireless operation).

Cabin Control (for large, heavy-duty cranes).

C. Safety Features

Overload limiter – Prevents exceeding safe capacity.

Limit switches – Stops trolley/bridge at preset positions.

Emergency stop – Instantly cuts power.

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4. Support & Auxiliary Components

A. Dust & Weather Protection

Enclosed motors/gearboxes (for harsh environments).

Dust-proof electrical components (in cement/coal handling).

B. Anti-Sway System

Reduces load swing for precise dumping.

Uses automated algorithms or mechanical dampers.

C. Weighing System (Optional)

Load cells integrated into the hoist for real-time weighing.

SKETCH

Main technical

 

 

Efficient Bulk Handling

Designed specifically for loose materials like coal, grain, sand, and scrap

Faster loading/unloading compared to manual methods or excavators

Typical cycle time of 30-60 seconds for full operation (grab, lift, move, dump)

Versatile Material Handling

Multiple grab types available:

Clamshell for free-flowing materials (capacity 3-50m³)

Orange peel for scrap metal (jaw opening up to 3m)

Electro-hydraulic for precision operations

Space Optimization

Works in confined areas where front-end loaders cannot operate

Can serve multiple stockpiles or storage areas from single runway

Reduced Material Loss

Enclosed grabbing minimizes spillage (critical for expensive materials)

Typical material loss <1% compared to 3-5% with front-end loaders

Automation Potential

Easily integrated with PLC systems for automated stockyard management

Can be equipped with weighing systems (accuracy ±0.5% of rated capacity)

Cost Efficiency

Lower operating cost than wheel loaders (approx. 30-40% savings)

Longer service life (20+ years with proper maintenance)

 

1. Ports and Terminals

Ship loading/unloading (rates up to 800-1,200 tons/hour)

Coal, iron ore, grain, and fertilizer handling

Stockyard management (stacking/reclaiming)

2. Steel Industry

Scrap metal handling (20-50 ton grabs common)

Blast furnace charging

Slag handling (special heat-resistant grabs available)

3. Power Generation

Coal handling for power plants

Ash removal systems

Biomass fuel handling

4. Cement Production

Raw material handling (limestone, clay)

Clinker transport

Fly ash management

5. Waste Management

Municipal solid waste handling

Recycling center operations

Incinerator feeding

6. Agriculture

Grain silo operations (3-10 ton capacity typical)

Fertilizer handling

Feed stock management

7. Mining

Ore handling at processing plants

Stockpile management

Tailings handling

Technical Specifications Comparison:

Application	Typical Capacity	Grab Type	Special Features
Coal Terminal	10-50 tons	Clamshell	Dust suppression
Scrap Yard	5-30 tons	Orange Peel	Heavy-duty jaws
Grain Silo	3-10 tons	Clamshell	Food-grade materials
Power Plant	5-20 tons	Clamshell	Explosion-proof

 

1. Design and Engineering
Confirm technical specifications (load capacity, span, lifting height).

Structural design of main beams, end carriages, trolley, and hoisting system using CAD and FEA software.

Electrical and control system layout design.

Compliance checks with relevant standards (ISO, FEM, OSHA).

2. Material Procurement
Source high-quality steel plates, structural steel sections, motors, electrical components, limit switches, and safety devices.

Verify material certifications and quality standards.

3. Fabrication of Main Components
Cutting & Shaping: Use CNC plasma cutting or laser cutting for steel plates.

Welding: Assemble main beams, end carriages, trolley frames using precise welding techniques.

Heat Treatment: Stress relief welding distortion by heat treatment if required.

Machining: Machine wheel seats, bearing seats, shaft holes, and motor mounting points.

Surface Treatment: Sandblasting and applying primer, then coating with anti-corrosion paint.

4. Assembly of Mechanical Parts
Assemble main beams with end carriages.

Install wheelsets and axle assemblies.

Mount trolley frame and hoisting mechanism (drum, wire rope, hook block).

Install brakes and gearbox on motors.

5. Electrical System Installation
Install motors (hoist, trolley, bridge travel).

Mount electrical panels, control cabinets.

Wire all sensors, limit switches, alarms, and control devices.

Connect power cables and control cables.

6. Quality Control & Testing
Non-destructive testing (NDT): Weld inspections by ultrasonic or magnetic particle methods.

Dimensional inspection: Check critical dimensions and tolerances.

Electrical tests: Insulation resistance, continuity, and control circuit tests.

Load testing: Perform static and dynamic load tests at 100% and 125% rated load.

Functional testing: Test all crane movements, alarms, safety devices, and control systems.

7. Painting and Finishing
Final painting for corrosion resistance and aesthetics.

Apply safety markings and labels.

8. Packaging and Delivery
Disassemble components if needed for transport.

Secure packaging to avoid damage during shipment.

Prepare manuals, certificates, and test reports.

9. Installation and Commissioning (On-site)
Assemble crane components on-site.

Align rails and fix end stops.

Connect power supply and control system.

Conduct on-site testing and operator training.

Final acceptance and handover.

Workshop view:

The company has installed an intelligent equipment management platform, and has installed 310 sets (sets) of handling and welding robots. After the completion of the plan, there will be more than 500 sets (sets), and the equipment networking rate will reach 95%. 32 welding lines have been put into use, 50 are planned to be installed, and the automation rate of the entire product line has reached 85%.