1. Main Girder

The primary load-bearing structure of the crane.

Usually fabricated as a welded box girder from high-strength steel plates.

Supports the hoist and transfers the load to the end carriages.

Designed to minimize deflection while maintaining a lightweight structure.

2. End Carriages (End Trucks)

Installed at both ends of the main girder.

Equipped with wheels that travel on the runway rails.

Support the bridge structure and provide crane traveling motion.

3. Electric Wire Rope Hoist

The core lifting unit consisting of:

Lifting motor

Gear reducer

Wire rope drum

Steel wire rope

Hook block

Electromagnetic brake

Functions:

Lifting and lowering loads up to 20 tons.

Moving along the main girder for cross-travel operation.

 

4. Hoist Traveling Mechanism

Travel motor

Drive wheels

Gear transmission system

Wheel brackets

Function:

Moves the hoist horizontally along the main girder.

5. Crane Traveling Mechanism

Crane travel motors

Gearboxes

Drive shafts (if applicable)

Travel wheels

Function:

Moves the entire crane bridge along the runway rails.

 

6. Hook Block Assembly

Forged crane hook

Pulley sheaves

Hook nut

Safety latch

7. Steel Wire Rope

High-strength galvanized or non-galvanized wire rope.

Wound around the hoist drum.

Transmits lifting force from the hoist to the hook block.

8. Electrical Control System

Includes:

Main electrical panel

Variable Frequency Drive (VFD) (optional)

Contactors and relays

Circuit breakers

Power distribution units

Function:

Controls lifting, cross travel, and long travel motions.

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9. Power Supply System

Busbar system or festoon cable system.

Supplies electrical power to crane movements and hoist operations.

10. Control Devices

Pendant Control

Wired push-button station suspended from the crane.

Wireless Remote Control

Allows operators to control the crane remotely.

 

11. Runway Rail System

Rails mounted on workshop support beams.

Guides crane movement along the building length.

12. Safety Devices

Overload Limiter

Prevents lifting loads exceeding rated capacity.

Upper & Lower Limit Switches

Prevent over-hoisting and over-lowering.

Travel Limit Switches

Restrict crane and hoist travel within safe limits.

Emergency Stop Button

Instantly stops crane operation during emergencies.

Phase Protection Relay

Protects motors from phase loss or phase reversal.

Buffers

Installed at runway ends to absorb impact.

Rail Sweepers

Remove debris from crane travel paths.

Audible & Visual Alarm (Optional)

Warns personnel when the crane is operating.

 

 

Sketch

 

Main technical

 

Advantages of a 20 Ton Electric Single Girder Overhead Crane for Indoor Workshops

1. Cost-Effective Solution

Lower manufacturing cost compared to double girder overhead cranes.

Reduced installation and maintenance expenses.

Excellent return on investment for medium-duty lifting applications.

2. High Working Efficiency

Enables quick lifting, lowering, and transportation of heavy materials.

Reduces manual handling and labor requirements.

Improves production flow and workshop productivity.

3. Space-Saving Design

Utilizes overhead space without occupying valuable floor area.

Allows unobstructed movement of personnel, vehicles, and equipment below.

Ideal for workshops with limited operating space.

4. Lightweight Structure

Single girder design has lower self-weight than double girder cranes.

Reduces load on building columns and runway beams.

Can lower workshop construction costs.

5. Smooth and Precise Operation

Equipped with electric wire rope hoists for stable lifting.

Variable Frequency Drive (VFD) control can provide smooth acceleration and deceleration.

Minimizes load swing and improves positioning accuracy.

6. Easy Installation

Modular design simplifies transportation and assembly.

Shorter installation and commissioning time.

Suitable for both new workshops and existing facilities.

7. Low Maintenance Requirements

Fewer structural and mechanical components.

Easy access to motors, brakes, and electrical systems.

Reduced downtime and maintenance costs.

8. Reliable Safety Performance

Equipped with multiple safety devices, including:

Overload protection

Emergency stop system

Upper and lower limit switches

Travel limit switches

Phase-loss protection

Buffers and rail sweepers

Ensures safe operation and protection of personnel and equipment.

9. Flexible Control Options

Pendant push-button control

Wireless remote control

Operator cabin control (optional)

Operators can choose the most suitable control method for their working environment.

10. Wide Application Range

Suitable for handling:

Steel structures

Machinery and equipment

Molds and dies

Fabricated components

Industrial materials

Warehouse cargo

11. Energy Efficient

Modern motors offer high efficiency and low power consumption.

Optional VFD systems help reduce energy usage and mechanical wear.

Supports environmentally friendly industrial operations.

12. Customizable Design

Can be customized according to project requirements:

Span length

Lifting height

Travel speed

Power supply

Duty classification

Control system

Special lifting attachments

13. Improved Workplace Safety

Reduces dependence on forklifts and manual lifting.

Minimizes risks associated with moving heavy loads.

Enhances overall workshop safety and operational control.

Summary

A 20 Ton Electric Single Girder Overhead Crane provides an ideal balance of lifting capacity, efficiency, safety, and economy. Its lightweight structure, low operating costs, reliable performance, and adaptability make it one of the most popular lifting solutions for indoor workshops, manufacturing plants, warehouses, and maintenance facilities requiring medium-duty material handling.

 

A 20 Ton Electric Single Girder Overhead Crane is widely used for lifting, transporting, loading, unloading, and positioning heavy materials and equipment within indoor industrial facilities. Its efficient operation and cost-effective design make it suitable for a variety of medium-duty applications.

1. Manufacturing Workshops

Handling raw materials and finished products.

Moving machine components between production stations.

Supporting assembly line operations.

Loading and unloading heavy equipment.

2. Steel Fabrication Plants

Lifting steel plates, beams, pipes, and structural components.

Transporting fabricated steel structures for welding and assembly.

Assisting in cutting, machining, and finishing operations.

3. Machinery Manufacturing Facilities

Handling large machine parts and assemblies.

Positioning components during manufacturing and testing.

Loading finished machinery for shipment.

4. Equipment Maintenance Workshops

Removing and installing motors, pumps, gearboxes, and heavy machinery.

Supporting repair and overhaul activities.

Facilitating equipment inspection and maintenance.

5. Warehouses and Distribution Centers

Loading and unloading heavy cargo.

Moving palletized materials and industrial goods.

Improving storage and retrieval efficiency.

6. Mold and Die Manufacturing Plants

Handling heavy molds and dies.

Transporting tooling between machining, assembly, and storage areas.

Assisting with mold installation and replacement.

7. Power Equipment Manufacturing

Lifting generators, transformers, switchgear, and electrical equipment.

Supporting assembly and testing processes.

Handling large fabricated components safely.

8. Construction Material Factories

Transporting concrete products, steel reinforcements, and building materials.

Supporting production and storage operations.

Loading products for transportation.

9. Automotive and Heavy Equipment Workshops

Moving engines, chassis components, and assemblies.

Assisting vehicle and equipment manufacturing processes.

Supporting maintenance and repair operations.

10. Paper, Textile, and General Industrial Plants

Handling production materials and equipment.

Supporting routine manufacturing operations.

Improving workflow efficiency and reducing manual labor.

Typical Materials Handled

Steel plates and structural steel

Machinery components

Fabricated metal products

Molds and dies

Industrial equipment

Mechanical assemblies

Construction materials

Heavy warehouse cargo

Pumps, motors, and gearboxes

Key Benefits in These Applications

Increased productivity and throughput.

Reduced manual handling and labor costs.

Improved workplace safety.

Efficient utilization of overhead space.

Accurate positioning of heavy loads.

Reliable operation for daily industrial use.

The 20 Ton Electric Single Girder Overhead Crane is particularly suitable for indoor facilities requiring frequent lifting operations, moderate duty cycles, and economical material handling solutions, making it a preferred choice across manufacturing, fabrication, maintenance, and warehousing industries.

 

20 Ton Electric Single Girder Overhead Crane Production Procedure

1. Engineering Design

Design Requirements Analysis

Confirm lifting capacity, span, lifting height, duty class, and workshop dimensions.

Determine hoist specifications and control methods.

Verify compliance with applicable standards and customer requirements.

Detailed Engineering Design

Main girder structural design.

End carriage design.

Hoist selection and configuration.

Electrical control system design.

Safety device arrangement.

Technical Documentation

General assembly drawings.

Fabrication drawings.

Electrical schematics.

Quality inspection plans.

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2. Raw Material Procurement and Inspection

Material Procurement

Structural steel plates.

Steel sections and profiles.

Motors and gearboxes.

Electrical components.

Wire ropes and hooks.

Incoming Quality Inspection

Verify material certificates.

Check dimensions and specifications.

Inspect surface quality.

Conduct material testing when required.

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3. Main Girder Fabrication

Steel Plate Cutting

CNC plasma or flame cutting according to fabrication drawings.

Edge preparation for welding.

Plate Forming

Web and flange plate bending.

Dimensional verification.

Girder Assembly

Position web and flange plates on assembly platform.

Install stiffeners and reinforcement plates.

Welding

Automatic submerged arc welding (SAW).

CO₂ gas shielded welding for auxiliary components.

Weld quality inspection.

Girder Straightening

Correct welding deformation.

Check camber and deflection requirements.

Dimensional Inspection

Span accuracy.

Diagonal measurements.

Girder alignment and straightness.

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4. End Carriage Manufacturing

Component Cutting and Machining

End beam fabrication.

Wheel seat machining.

Bearing housing preparation.

Assembly

Install wheels, bearings, and drive shafts.

Mount travel motors and reducers.

Inspection

Wheel alignment check.

Dimensional verification.

Rotation testing.

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5. Hoist Assembly

Mechanical Assembly

Drum installation.

Gearbox assembly.

Motor installation.

Brake installation.

Wire Rope Installation

Wire rope winding.

Rope fixing and tension adjustment.

Hook Block Assembly

Hook installation.

Pulley assembly.

Safety latch installation.

Functional Testing

Lifting operation test.

Brake performance verification.

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6. Machining Process

Precision Machining

Wheel machining.

Shaft machining.

Coupling preparation.

Bearing seat finishing.

Quality Control

Dimensional measurement.

Surface finish inspection.

Tolerance verification.

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7. Surface Preparation

Shot Blasting

Remove rust, scale, and contaminants.

Achieve required surface cleanliness grade.

Surface Inspection

Check cleanliness and roughness.

Verify preparation quality before painting.

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8. Painting Process

Primer Coating

Apply anti-corrosion primer.

Intermediate Coating

Improve corrosion resistance and coating thickness.

Finish Coating

Apply customer-specified color.

Ensure uniform appearance and protection.

Drying and Curing

Allow sufficient curing time before assembly.

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9. Electrical System Assembly

Control Panel Fabrication

Install contactors, breakers, relays, and protection devices.

Wire electrical circuits according to schematics.

Electrical Installation

Festoon cable system installation.

Limit switch installation.

Power supply system assembly.

Control Devices Installation

Pendant control station.

Wireless remote control system (if specified).

Warning alarms and indicator lights.

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10. Complete Crane Assembly

Mechanical Assembly

Connect main girder and end carriages.

Install hoist on girder.

Assemble travel mechanisms.

Electrical Integration

Connect motors and control systems.

Install cable routing systems.

Verify grounding protection.

Safety Device Installation

Overload limiter.

Travel limit switches.

Emergency stop system.

Buffers and rail sweepers.

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11. Quality Inspection

Structural Inspection

Weld quality examination.

Dimensional inspection.

Visual inspection.

Mechanical Inspection

Wheel alignment.

Gearbox operation.

Brake performance.

Electrical Inspection

Insulation resistance testing.

Circuit continuity verification.

Control function testing.

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12. Factory Acceptance Testing (FAT)

No-Load Testing

Hoist operation.

Cross travel operation.

Long travel operation.

Static Load Test

Test at 125% of rated capacity (25 tons).

Verify structural integrity and deflection.

Dynamic Load Test

Test at 110% of rated capacity (22 tons).

Evaluate operational performance.

Safety Function Testing

Overload protection.

Limit switches.

Emergency stop functions.

Braking system performance.

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13. Packing and Shipment

Component Protection

Protect machined surfaces.

Secure electrical components.

Wrap sensitive equipment.

Export Packing

Steel structure packing.

Wooden cases for electrical parts and accessories.

Container loading preparation.

Shipping Documentation

Packing list.

Inspection reports.

Operation and maintenance manuals.

Quality certificates.

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14. Site Installation and Commissioning

Installation

Runway inspection.

Crane erection.

Hoist installation.

Electrical connections.

Commissioning

System adjustment.

Operational testing.

Load testing.

Final Acceptance

Customer inspection.

Performance verification.

Operator training.

Project handover.

4. Main Girder Fabrication

The girder is assembled and welded into a box structure.

Process

Plate positioning

Tack welding

Automatic submerged arc welding

Reinforcement installation

Camber control

Key Requirements

Dimensional accuracy

Welding quality

Deflection control

5. End Carriage Manufacturing

End carriages are fabricated and assembled separately.

Components

Wheel blocks

Bearing housings

Drive shafts

Motor seats

Processes

Welding

Machining

Assembly alignment

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6. Machining Process

Critical components are precision machined.

Machined Parts

Wheel assemblies

Bearing seats

Couplings

Gearbox interfaces

Equipment

CNC milling machines

Boring machines

Lathes

 

7. Welding Inspection & NDT

Weld quality inspection ensures structural safety.

Inspection Methods

Visual inspection

Ultrasonic testing (UT)

Magnetic particle testing (MT)

Dimensional inspection

Objectives

Detect welding defects

Ensure structural integrity

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9. Electrical System Installation

Main Components

Control cabinet

Frequency inverters (VFD)

Contactors and relays

Limit switches

Power supply system

Wiring

Cable routing

Terminal connections

Grounding installation

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10. Complete Crane Assembly

Mechanical Assembly

Main girder and end carriage connection

Trolley installation

Hoist installation

Wheel alignment

Electrical Assembly

Power system connection

Control system integration

Safety device installation

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11. Quality Inspection and Testing

Dimensional Inspection

Span verification

Camber measurement

Assembly accuracy inspection

Electrical Inspection

Insulation resistance test

Continuity test

Grounding verification

Mechanical Inspection

Wheel alignment check

Brake performance test

Drive system inspection

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12. Functional Testing

No-Load Test

Hoist operation

Trolley travel

Crane travel

Control functions

Safety Device Test

Emergency stop

Limit switches

Overload limiter

Protection systems

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13. Load Testing

Static Load Test

125% of rated load

Load held for specified duration

Structural deformation inspection

Dynamic Load Test

110% of rated load

Lifting and traveling operations

Performance verification

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14. Final Inspection and Certification

Complete quality audit

Test report preparation

Inspection certificate issuance

Customer witness inspection (if required)

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15. Packaging and Delivery

Packaging

Hoist protection wrapping

Electrical component protection

Rust prevention treatment

Shipping Preparation

Component marking

Packing list preparation

Loading into containers or trucks

Export documentation preparation

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%.