Customized 15-Ton Double Girder Bridge Crane for Pakistani Steel Coil Plant

Project Overview

Dongqi Crane successfully designed and manufactured a specialized QDX-type 15-ton double girder bridge crane for a leading steel coil manufacturer in Pakistan. This heavy-duty lifting solution was engineered to meet the demanding requirements of steel coil handling operations in a high-temperature industrial environment.

Technical Specifications

• Model: QDX Double Girder Bridge Crane
• Capacity: 15 metric tons (with 20% overload capacity)
• Span: 35 meters (custom-designed for workshop layout)
• Lifting Height: 6.45 meters (optimized for coil stacking)
• Power Supply: 415V/50Hz/3P (compliant with local standards)
• Control System: Remote pendant control only (no cabin operation)
• Operating Temperature: Designed for up to 55°C ambient temperature

1. Structural Components

• Main Girders
  • Material: Q345B steel (equivalent to ASTM A572 Grade 50)
  • Construction: Welded box girder design
  • Dimensions: 35m span × 1.2m height × 0.8m width
  • Deflection: ≤1/800 of span under full load (43.75mm max)
• End Trucks
  • Wheel diameter: Φ500mm forged steel
  • Wheel bearings: SKF spherical roller bearings
  • Buffers: Polyurethane with 50mm stroke

2. Hoisting Mechanism

• Electric Hoist
  • Capacity: 15 ton (SWL)
  • Lifting speeds: 8 m/min (full load), 0.8 m/min (precision)
  • Motor power: 18.5kW S3 40% duty cycle
  • Braking system: Dual brakes (main + emergency)
• Load Chain
  • Type: Grade 80 alloy steel
  • Diameter: Φ14mm
  • Safety factor: 5:1 minimum breaking strength

3. Trolley System

• Travel Mechanism
  • Drive: 2×3.7kW AC motors
  • Speed: 15 m/min
  • Wheel arrangement: 4-wheel, 2 driven
  • Rail type: QU70 (70kg/m)

4. Electrical System

• Power Supply
  • Voltage: 415V ±10%
  • Frequency: 50Hz ±2%
  • Phases: 3P + PE
  • Protection: IP54 enclosure rating
• Control System
  • Operation: Wireless remote control (2.4GHz)
  • Range: 100m line-of-sight
  • Functions: Emergency stop, speed selection, overload cut-off

5. Safety Features

• Protection Devices
  • Overload limiter (110% cut-off)
  • Upper/lower limit switches
  • Phase failure protection
  • Emergency stop button (2 locations)
• Structural Safety
  • Working load limit: 15 ton
  • Test load: 18.75 ton (125%)
  • Design factor: 1.5× maximum stress

6. Environmental Specifications

• Operating Conditions
  • Temperature range: -20°C to +55°C
  • Humidity: ≤95% RH (non-condensing)
  • Altitude: ≤1000m ASL
• Special Protection
  • Heat-resistant paint (up to 200°C)
  • Corrosion protection: 200μm epoxy coating
  • Dust protection: IP54 sealing

7. Performance Metrics

• Positioning Accuracy
  • Horizontal: ±10mm
  • Vertical: ±5mm
  • Rotation: ±1°
• Noise Levels
  • ≤75dB at 1m distance
  • ≤65dB at operator position

This detailed technical specification sheet provides comprehensive engineering data for the 15-ton double girder bridge crane, ensuring complete transparency about the equipment’s capabilities and compliance with international standards. All specifications are subject to final confirmation based on specific project requirements.

Key Engineering Features

1. Structural Design

• Reinforced box girder construction with FEM-standard calculations
• Special anti-deflection design for 35m span application
• Corrosion-resistant paint system suitable for coastal climate

2. Lifting Mechanism

• Dual-speed hoisting system (8/0.8 m/min)
• Coil-specific C-hook attachment with rotation function
• Grade 80 high-tensile load chain with wear indicators

3. Electrical System

• Variable frequency drive for smooth acceleration/deceleration
• IP54 protection for dust and moisture resistance
• Thermal protection for all motors and electrical components
• Wireless remote control system with emergency stop function

Project Implementation

Site-Specific Adaptations

• Customized runway beams for existing workshop structure
• Special heat shielding for electrical components
• Vibration damping system for precise load positioning
• Operator training program for remote pendant operation

Performance Metrics

• Cycle Time: 25% improvement over previous system
• Positioning Accuracy: ±5mm for precise coil placement
• Energy Efficiency: 18% reduction in power consumption
• Operator Safety: Enhanced visibility and ergonomics with remote control

Client Benefits

• Enhanced safety through remote operation away from load
• Lower total cost of ownership
• Increased production throughput with optimized controls
• Reduced maintenance requirements

Why Dongqi Crane?

• 15+ years experience in metallurgical cranes
• CE-certified manufacturing processes
• Local technical support in Pakistan
• Custom engineering solutions for special applications
• Expertise in remote-controlled crane systems

For your steel plant crane requirements, contact our engineering team today to discuss customized solutions.

Dongqi Crane – Lifting Solutions for Heavy Industry
Email: sales010@cranesdq.com
Website: https://sg.craneyt.com/