Case Study: Dongqi Crane’s Explosion-Proof QDX Bridge Cranes Enhance Safety in Nigerian Factory

Reliable lifting solutions for hazardous environments

In 2025, Dongqi Crane successfully manufactured and delivered two explosion-proof QDX double girder overhead cranes to a manufacturing facility in Nigeria, specifically engineered for operation in potentially hazardous environments where explosive gases may be present.

These advanced cranes represent Dongqi’s commitment to safety, reliability, and technological innovation in specialized industrial applications.

Project Overview

Dongqi Crane provided two customized QDX series double girder overhead cranes with the following technical specifications:

• Lifting Capacity: 15 tons per crane
• Span: 13 meters
• Lifting Height: 8.95 meters
• Power Supply: 400V, 50Hz, 3-phase
• Explosion Protection Rating: Ex II 2 G Ex de IIC T4
• Quantity: 2 units

Advanced Explosion-Proof Features

The cranes were meticulously engineered with comprehensive safety measures for operation in potentially explosive environments:

Mechanical Safety Components

• Specialized crane wheels made of stainless steel or nylon to prevent friction-generated sparks .
• Asbestos-free brake linings that activate automatically in case of power failure .
• Spark-resistant bumper systems using rubber or polyurethane materials with controlled insulation resistance .
• Protected hook surfaces designed to prevent collision or friction that could generate dangerous sparks .

Electrical Safety Systems

• Complete explosion-proof electrical system with all motors and electrical equipment manufactured in compliance with international explosion-proof standards .
• Flameproof enclosures (Ex d) and increased safety (Ex e) designs meeting CE marking requirements .
• Explosion-proof control systems including flameproof motors and separate power supply for critical components .
• Cable management using steel pipe wiring and flexible cables with proper grounding .

Technical Excellence of QDX Series Cranes

The QDX European double girder overhead cranes represent Dongqi’s advanced engineering capabilities with several distinctive features:

Structural Advantages

• Compact design with reduced headroom requirements for maximum space utilization .
• Light dead weight compared to traditional double girder cranes, reducing structural load on building supports .
• Modular construction enabling easier maintenance and component replacement .

Performance Characteristics

• Smooth operation through advanced control systems for precise load handling .
• Robust construction capable of handling the specified 15-ton capacity with operational reliability .
• Enhanced safety features including electronic overload protection with warning systems .

Purpose-Built for Hazardous Environments

These cranes were specifically engineered for Zone 1 hazardous areas where explosive gas atmospheres are likely to occur in normal operation . The Ex IIC T4 rating indicates suitability for environments with gases and vapors with ignition temperatures above 135°C .

The comprehensive safety approach extends beyond the electrical components to include all potential ignition sources, ensuring complete protection for the Nigerian facility’s specific operational requirements.

Quality Assurance and Testing

Prior to delivery, both cranes underwent rigorous factory testing and inspection to verify all explosion-proof characteristics and operational safety systems. The testing included:

• Performance verification under simulated working conditions
• Explosion-proof component validation to ensure compliance with specified standards
• Safety system checks including all protective devices and emergency controls
• Detailed documentation of all test results for client review

Factory testing of the explosion-proof crane systems prior to shipment to Nigeria

Dongqi’s Expertise in the Nigerian Market

This project continues Dongqi Crane’s established presence in Nigeria, building on previous successful installations including:

• 50/10 ton double girder overhead cranes for material handling applications .
• 25 ton double girder cranes for precast concrete plants with specialized concave trolleys for limited headroom .

Conclusion

The successful implementation of these explosion-proof QDX bridge cranes in Nigeria demonstrates Dongqi Crane’s capability to deliver specialized, safety-critical lifting solutions for challenging industrial environments.

By combining advanced explosion-proof technology with the proven performance of the QDX double girder design, Dongqi has provided the Nigerian client with a reliable, safe, and efficient material handling solution that meets international safety standards while addressing the specific requirements of their operational environment.

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Dongqi Crane provides customized lifting solutions for industries worldwide. For more information about our explosion-proof equipment or other crane systems, contact our engineering team today.