The finishing mill unit of our high-speed wire rod plant utilizes a 45° top-crossing cantilever design from Danieli, commissioned in 2015 for producing Φ5.5-Φ16mm wire rod. This 8-stand unit reaches maximum speeds of 116m/s. Initial operation revealed persistent issues including roll box water ingress, TC ring cracking, and locking device jams, significantly impacting production. A dedicated team was established to address these challenges.
Common Accident Analysis and Solutions
1.1 Roll Box Water Ingress
Root Causes:
Excessive clearance between outer oil thrower ring and panel, allowing high-pressure cooling water entry
Deformed panels from installation damage or operational incidents
Incompatible materials in double-lip seals causing premature aging
Insufficient compressed air pressure failing to maintain effective sealing
Solutions:
Standardize installation protocols for panel flatness and joint surfaces
Implement grinding treatment for panel contact surfaces
Prohibit metal tools during assembly to prevent damage
Verify seal integrity and proper interference fit during installation
Upgrade seal materials for improved oil resistance and temperature tolerance
Maintain compressed air pressure within specified ranges with regular pipe cleaning
Establish assembly standards and regular spare parts replacement schedules
1.2 Roll Ring Fragmentation
Accident Analysis:
Improperly locked roll rings causing relative rotation and frictional heat generation
Insufficient cooling water pressure and flow leading to elevated temperatures
Thermal shock from sudden cooling of high-temperature roll rings
Internal manufacturing defects in roll rings
Preventive Measures:
Standardize roll ring installation with clean, oil-free interfaces
Regular measurement of taper dimensions for cones and shafts
Maintain adequate cooling water pressure with alarm systems
Implement natural cooling for heat-affected roll rings
Replace with new roll rings for urgent production requirements
Regular nozzle cleaning to prevent blockages
Through systematic implementation of these measures, the high-speed wire rod plant has significantly improved equipment reliability and reduced production interruptions, establishing a foundation for stable operation and consistent product quality.
