Views: 0 Author: Site Editor Publish Time: 2026-07-22 Origin: Site
Xinjiang Zijin Nonferrous Metals Co., Ltd. is located in the Wuqia County industrial development zone, Xinjiang, at an altitude of approximately 2,200 meters. The region has harsh winters with extreme temperatures dropping to -29.9°C, persistent sandstorms, and low atmospheric pressure.
The rotary kiln workshop's water-quenched slag pool maintains high water temperatures, creating year-round dense fog that impairs manual crane operator visibility, reducing slag removal efficiency and creating safety risks. In the roasting workshop, raw material feeding generates heavy ore dust, obstructing cabin visibility and affecting batching accuracy and operator health.
The existing cranes needed precision XYZ-axis positioning and automated grabbing, transferring, and dumping, with three operation modes—fully automatic, remote manual, and remote control—plus multi-level safety protection, intelligent 3D warehouse management, and reliable wireless communication under harsh conditions.
Wuhan Forward Technology handled the complete design, supply, installation, and commissioning of the intelligent systems on a turnkey basis.
1. Multi-Source Integrated Positioning System
For the comprehensive recovery plant, where fog is a major issue, we used a Gray code bus positioning system for the X/Y axes. It delivers ±2mm accuracy with absolute positioning—no homing required—and is unaffected by fog or dust. For the Z-axis (hoist and closure), we used KUBLER multi-turn absolute encoders with PROFINET interface, which retain data through power outages. The roasting workshop uses laser rangefinders instead.
Our multi-source data fusion algorithm combines Gray code bus, encoder, and laser rangefinder signals in real time to give accurate absolute coordinate feedback across the full travel range.
2. Anti-Sway Control
We built an anti-sway controller that calculates load rope length in real time and adjusts bridge and trolley speeds accordingly. Field measurements show positioning deviation within ±25mm and sway elimination above 95%, which cuts down the waiting time for the load to stabilize.
3. Intelligent Grab Control
We developed two features on the grab control side.
Deep-digging: when the grab closes, the system switches to torque mode so the grab keeps descending without the cables going slack, reaching deeper material and improving fill factor.
Slack and tangle prevention: a real-time cable tension monitor detects slack and automatically cuts descent or adjusts speed to prevent the grab from tipping or the cables from dislodging.
4. 3D Laser Scanning and Real-Time Modeling
The crane carries a laser radar with a pan-tilt unit. Combined with the crane's positioning system, our point cloud processing software builds a 3D model of the material yard, segments stockpile boundaries, calculates volume, weight, and highest/lowest points, and generates grabbing, transferring, and replenishment work orders based on material type and stacking rules.
The radar also scans ahead for obstacles and feeds that data to the PLC for active collision avoidance.
5. Multi-Level Safety Protection
We set up virtual deceleration and stop zones using absolute positioning coordinates. Laser rangefinders at both ends of each crane trigger emergency braking when adjacent cranes or track obstacles get too close. Mechanical limit switches serve as a final backup.
The system also verifies data redundancy and monitors communications—if the link drops or slows too much, it locks out and alarms. Operator access is controlled with tiered password authorization.
6. High-Reliability Wireless Communication
Wireless communication uses industrial-grade 5.8GHz bridges, with separate links for control (300Mbps) and video (866Mbps). They support TDMA, DFS, and anti-interference, with IP68 protection, -40~75°C operating range, and seamless roaming.
7. Intelligent Warehouse Management Platform
The platform reconstructs the yard in 3D from real-time point cloud data, showing equipment positions and stockpile changes. The work order engine interfaces with ERP/MES to break down and dispatch batching, transferring, and inbound/outbound plans.
A black-box module logs all sensor and PLC data before and after faults for fast troubleshooting. Reports on workload, inventory, and equipment status are generated automatically.
8. Control Room Hardware and Video Surveillance
The control room includes HPE rack servers, Dell industrial PCs, dual 27-inch displays, and a 32U network cabinet with a 2KVA UPS (providing over 30 minutes of backup). Four 4MP cameras on the crane and three on the ground cover the entire area, with video stored for more than six months.
Once the system went live, positioning accuracy held within ±25mm, meeting the requirements for automated grabbing and dumping. With sway elimination above 95%, the single-cycle time dropped about 40% compared to manual operation.
The grab fill factor climbed from roughly 70% before the retrofit to over 95%. Variable frequency drives and path optimization cut energy consumption by about 15% per crane.
Since commissioning, there have been no collisions, over-travel incidents, or grab tipping accidents. The black-box diagnostics reduced average fault localization time from around four hours to under 1.5 hours.
Fully automatic mode now handles about 90% of daily workload, with remote control and manual modes kept as backup.
