ADVANTAGES OF LH MODEL

Cost-Effectiveness

Standardized components reduce manufacturing cost

Bulk production of common capacity ranges (5t, 10t, 16t, 20t, 32t)

Simplified design lowers maintenance costs

Reliability & Simplicity

Proven design with decades of industrial use

Easy maintenance - components are accessible and standardized

Robust construction suitable for general industrial environments

Flexibility

Modular design allows for customization

Multiple control options (pendant, cab, remote)

Compatible with various lifting attachments (hook, magnet, grab)

 

COMPARISON: LH vs. Other Double Girder Cranes

Feature	LH Model	European Design	Heavy-Duty Custom
Cost	Low-Medium	High	Very High
Duty Class	A3-A5 (Medium)	A6-A7 (Heavy)	A7-A8 (Very Heavy)
Design	Standardized	Optimized	Custom-engineered
Lead Time	Short (8-12 weeks)	Medium (12-20 weeks)	Long (20-30+ weeks)
Components	Domestic/Chinese	European brands	Global premium brands
Lifespan	15-20 years	25-30 years	30+ years

 

When to Choose LH Model

✅ General industrial applications (not extreme duty)

✅ Budget constraints without sacrificing safety

✅ Standard capacity requirements (≤ 80 tons)

✅ Moderate usage (≤ 15-20 lifts/hour)

✅ Indoor or sheltered environments

When to Consider Alternatives

❌ Severe duty cycles (steel mills, scrap yards)

❌ Corrosive environments (chemical plants, marine)

❌ Very high precision requirements (±1mm)

❌ Extreme temperatures outside -20°C to +40°C

❌ Explosive atmospheres (requires EX-rated equipment)

 

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

The LH Model Double Girder Overhead Crane is a widely used lifting system equipped with an electric hoist trolley, offering compact design, stable performance, and high lifting efficiency. Its main components include the following:

1. Double Box Girders (Bridge Structure)

Two welded box-type girders

High rigidity and excellent load-bearing capacity

Designed with proper camber to reduce deflection

Equipped with rail for trolley traveling

 

2. End Carriages (Crane Traveling Mechanism)

Welded box structure end beams

Driven by electric motors and reducers

Forged or cast-steel crane wheels

Equipped with:

Buffer devices

Limit switches

Wheel guards

3. Electric Hoist Trolley

The core lifting unit of LH model cranes.

Includes:

Electric wire rope hoist (type: CD/MD/HC/HD)

Trolley frame

Hoist motor and reducer

Lifting drum and wire rope

Hook block and sheave system

Trolley traveling motor and gearbox

Brake system

This compact trolley is mounted between the double girders for maximum lifting height.

4. Crane Traveling Mechanism

Two or four drive motors depending on capacity

Gearbox and brake system

Couplings and drive shafts

Frequency inverter (optional) for smooth speed control

 

7. Safety Protection Devices

Overload limiter

Lifting height limit switch

Trolley travel limit switch

Crane long travel limit switch

Emergency stop

Rail sweeper

Anti-collision device (optional)

Overspeed and brake monitoring (optional)

 

8. Power Supply System

Insulated conductor busbar / festoon cable system

Main isolating switch

Grounding system

Cable drag chains (for trolley movement)

 

9. Buffer and Rail System

Polyurethane or rubber buffers

Rail clamps and end stops

Crane rails (P24–P80 depending on capacity)

Summary of Main Components

Double Box Girders

End Carriages

Electric Hoist Trolley

Crane Traveling Mechanism

Electrical Control System

Control Methods

Safety Protection Devices

Power Supply System

Buffers and Rail Accessories

Sketch

Main technical

 

 

Advantages of LH Model Double Girder Overhead Crane

1. Large Lifting Capacity & High Strength

Double-girder design provides high rigidity and excellent load-carrying ability.

More suitable for medium to heavy lifting operations (5–50 tons).

2. Greater Lifting Height

The hoist trolley runs between the two girders, not under them.

Maximizes lifting height and usable workshop space.

3. Stable & Efficient Operation

Smooth lifting and traveling motion with minimal vibration.

High working efficiency for frequent material handling tasks.

4. Compact Structure & Lightweight Design

Uses an electric hoist trolley instead of a winch trolley.

Reduces equipment weight and overall cost while maintaining performance.

5. Easy Maintenance & Simple Assembly

Fewer components than a winch-type double girder crane.

Maintenance points are easy to access.

6. Cost-Effective Solution

Lower cost than traditional heavy-duty double girder cranes.

Ideal for medium-duty industrial operations.

7. Multiple Control Methods

Pendant control / Remote control / Cabin control (optional).

Supports frequency conversion for smooth speed regulation.

8. High Safety & Reliability

Equipped with overload protection, limit switches, emergency stop, rail sweeper, and anti-collision options.

Electrical components adopt Siemens/Schneider brands.

 

Applications of LH Model Double Girder Overhead Crane

The LH model is widely used for indoor material lifting in medium-duty industrial environments:

1. Manufacturing Workshops

Mechanical parts handling

Assembly lines

General production material movement

2. Warehouse & Logistics Centers

Loading, unloading, and transferring heavy goods

Efficient stock movement in large storage areas

3. Processing & Fabrication Plants

Steel structure fabrication

Metal processing

Equipment manufacturing

4. Power Plants & Electrical Equipment Workshops

Transformer handling

Generator parts lifting

Maintenance applications

5. Mining & Raw Material Processing

Mineral equipment handling

Maintenance and part replacement tasks

6. Chemical & Paper Industries

Handling large rolls, tanks, and machinery

Safe lifting of wrapped or packaged materials

7. Ports & Railway Cargo Yards (Indoor Use)

Heavy goods loading and unloading

Container parts and equipment lifting

 

The manufacturing of an LH Model Double Girder Overhead Crane follows a strict, standardized workflow to guarantee high strength, safety, and long service life. Below is the complete production procedure:

1. Raw Material Inspection & Preparation

Select high-quality Q235B / Q345B steel plates

Inspect steel for surface defects and internal flaws

Shot blasting to remove rust and scale

CNC cutting of plate components according to production drawings

2. Double Box Girder Fabrication

2.1 Plate Cutting & Forming

CNC plasma cutting of web plates, flanges, diaphragms

Bending and shaping of side plates (if required)

2.2 Girder Assembly

Positioning of web, flange, and rib plates

Tack welding using automatic fixtures

Internal diaphragm plates assembled inside the box structure

2.3 Automatic Welding

Longitudinal seams welded by gantry automatic welding machine

CO₂ gas-shielded welding for joints and end plates

2.4 Girder Straightening & Stress Relief

Mechanical straightening to correct deformation

Optional vibration stress relief or heat treatment

2.5 Nondestructive Testing

Magnetic Particle Testing (MT) on weld seams

Ultrasonic Testing (UT) for internal weld quality

3. End Carriage Fabrication

Box-type end beam structure welded and machined

Wheel shaft holes processed by CNC boring machine

Installation of:

Crane wheels (forged/cast steel)

Motors

Gear reducers

Brake systems

Final alignment check for smooth operation

4. Electric Hoist Trolley Assembly

4.1 Trolley Frame Fabrication

Precision-welded box-type structure

Machined to ensure dimensional accuracy

4.2 Hoist Unit Assembly

Lifting motor

Reducer and brake

Wire rope drum and shaft

Hook block with sheaves

Wire rope installation

4.3 Trolley Travel Mechanism

Motor + reducer + brake assembly

Driving wheels installed on trolley frame

5. Electrical System Manufacturing

Electrical cabinet assembly using Siemens/Schneider components

Wiring of power and control circuits

Installation of:

Limit switches

Overload limiter

Emergency stop

Remote control receiver (if applicable)

Optional PLC configuration for advanced controls

6. Surface Treatment & Painting

6.1 Shot Blasting

Girder and metal surfaces blasted to Sa2.5 standard

6.2 Painting

Typical paint system includes:

Epoxy zinc-rich primer

Epoxy intermediate coating

Polyurethane topcoat

Color customizable according to client requirements.

7. Crane Assembly & Pre-Assembly

Girders and end carriages bolted together

Hoist trolley mounted on girder rails

Cable festoon system or busbar installation

Power and control wiring connected

Factory Pre-Assembly Ensures:

Accurate alignment

Smooth travel movement

Functional safety devices

Electrical system operation

8. Factory Acceptance Testing (FAT)

Tests include:

No-load test

Dynamic load test (110% rated capacity)

Static load test (125% rated capacity)

Lifting, trolley travel, and crane travel tests

Verification of limit switches and safety devices

All tests follow GB/T, FEM, ISO, and CE standards.

9. Packing & Delivery

Electrical parts packed in wooden crates

Trolley protected with steel brackets

Girders wrapped with waterproof material

Shipped by container or bulk cargo

10. On-Site Installation & Commissioning

Girders installed on runway beams

Trolley and end carriages mounted

Rail alignment, cable installation, and control wiring

On-site load testing and operational checks

11. Final Acceptance & Training

Final inspection with client

Issue load test reports & certificates

Provide operator training and maintenance guidance

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%.