4 hi cold rolling mill(Hydraulic AGC Φ50/Φ80/Φ300×300 Φ80/Φ110×380/Φ350×350)
Brand name: HANI
Packing Details : Wooden box with fumigation or Wooden Fram or Steel Frame
Delivery Details: 30~60days or Based on the quantity
Shipping: Sea freight、Land freight、Air freight
HANI focuses on cold rolling mill equipment technology, safeguarding your production.
Product Details
The 4 hi cold rolling mill represents the pinnacle of precision metal processing technology. This Hydraulic AGC four-high precision cold rolling mill system is meticulously engineered to deliver unparalleled performance in the production of high-quality metal strips and foils across numerous industrial applications.
Technical Overview of the 4 hi Cold Rolling Mill
The 4 hi cold rolling mill with Hydraulic Automatic Gauge Control (AGC) system is specifically designed for manufacturing ultra-thin, high-precision metal strips with exceptional dimensional accuracy and surface finish. This advanced equipment implements computer-aided optimization techniques to maximize rigidity while maintaining an efficient weight-to-performance ratio.
Our 4 hi cold rolling mill configuration utilizes a unique four-high arrangement where small diameter work rolls are supported by larger backup rolls, allowing for processing of extremely thin materials while maintaining exceptional strip flatness and thickness consistency. The hydraulic AGC system continuously monitors and adjusts roll gap during operation to compensate for thermal expansion, roll wear, and material variations, ensuring consistent product quality throughout extended production runs.
Key Technical Specifications
| Parameter | Specification | Model Options |
|---|---|---|
| Roll Configuration | Four-high reversible mill with hydraulic AGC | Φ50/Φ80/Φ300×300, Φ80/Φ110×380/Φ350×350 |
| Maximum Rolling Speed | 60-120 m/min | Variable depending on material and thickness |
| Minimum Thickness | 0.05 mm | Achievable with appropriate material selection |
| Thickness Accuracy | ±0.004 mm @ 0.2 mm thickness | With AGC system active |
| Maximum Rolling Force | 150-300 tons (depending on model) | Customizable based on requirements |
| Control System | Full digital control with HMI interface | Siemens/ABB/Rockwell options available |
| Drive System | Backup roll driven, AC vector control | Power range: 160-500 kW |
| AGC System Response Time | < 10 ms | Real-time thickness adjustment |
Engineering Excellence in the 4 hi Cold Rolling Mill Design
The structural integrity of our 4 hi cold rolling mill begins with the monoblock frame design, manufactured from high-grade cast steel with finite element analysis optimization. This approach delivers exceptional rigidity—critical for maintaining tight thickness tolerances during high-speed operation. The frame’s stiffness coefficient exceeds 450 t/mm in larger models, significantly reducing elastic deformation under maximum rolling loads.
One of the distinguishing features of this 4 hi cold rolling mill is the optimized roll system configuration. Through computer simulation and extensive field testing, our engineering team has perfected the roll profile geometry to maximize edge stability while minimizing center buckle tendencies. The work rolls feature specialized crown profiles combined with dynamic bending control, allowing operators to compensate for thermal camber and wear patterns during extended production runs.
The hydraulic AGC system represents the technological heart of this 4 hi cold rolling mill. Utilizing high-response servo valves with resolution of 0.1μm, the system continuously monitors strip thickness through X-ray or beta-ray gauges positioned after the mill stand. This feedback loop makes up to 100 adjustments per second to the hydraulic cylinder positions, maintaining precise roll gap despite variations in incoming material thickness, temperature fluctuations, or roll thermal expansion.
HANI engineers have incorporated a unique roll change mechanism that reduces downtime by 60% compared to conventional designs. The quick-change cassette system allows complete work roll and backup roll replacement in under 15 minutes, dramatically improving equipment utilization rates for facilities running multiple product specifications.
Materials Processing Capabilities
The versatility of this 4 hi cold rolling mill extends across a remarkable range of metallic materials:
- Ferrous Alloys: Carbon steels (C1006-C1070), silicon electrical steels (M19-M43), stainless steels (301, 304, 316, 430), tool steels
- Non-Ferrous Metals: Copper and copper alloys (C10100-C72950), aluminum and aluminum alloys (1xxx-8xxx series), nickel alloys (Inconel, Monel), titanium alloys
- Precious Metals: Gold, silver, platinum alloys for specialized electronic and jewelry applications
- Specialty Alloys: Precision alloys (Kovar, Invar), amorphous and nanocrystalline alloys, shape memory alloys
The 4 hi cold rolling mill excels particularly in applications requiring extreme dimensional precision. For instance, when processing stainless steel 304 to a final thickness of 0.1mm, the hydraulic AGC system maintains thickness variation within ±0.003mm across the entire coil width. Similarly, when rolling copper alloy C70250 (a high-strength, high-conductivity material used in connector applications), the mill achieves surface roughness values of Ra 0.05-0.1μm while maintaining thickness tolerance of ±0.002mm.
Advanced Control Systems and Automation
Modern 4 hi cold rolling mill installations incorporate multi-level control architecture:
Level 1: Basic Automation – Real-time control of hydraulic cylinders, drive motors, and auxiliary systems with millisecond response times
Level 2: Process Optimization – Mathematical models predict roll force, torque, and power requirements based on material properties, reduction schedules, and thermal conditions
Level 3: Production Management – Quality tracking, maintenance scheduling, and production reporting integrated with plant ERP systems
The 4 hi cold rolling mill features a comprehensive hydraulic bending system for work rolls and backup rolls. This critical component allows operators to dynamically adjust strip flatness during operation by applying controlled bending forces at multiple points along the roll barrel. The system can be programmed to follow predetermined profiles or respond to automatic flatness measurement feedback from scanning sensors positioned at the mill exit.
Complementing the AGC system, the strip guiding mechanisms utilize high-precision optical sensors with position resolution of 1μm to maintain perfect strip alignment through the mill. This prevents edge damage and ensures uniform roll wear—critical factors in producing high-value specialty alloys where edge condition directly impacts downstream processing yield.
Installation Requirements and Facility Considerations
Successful integration of a 4 hi cold rolling mill requires careful planning of several facility elements:
| Requirement | Specification | Notes |
|---|---|---|
| Foundation | Reinforced concrete, minimum 1.5m depth | Vibration analysis required before construction |
| Power Supply | 400-6000 kVA, 3-phase, 50/60 Hz | Harmonic filtering may be required |
| Cooling System | Closed-loop, 20-100 m³/h capacity | Temperature stability ±1°C critical |
| Compressed Air | 7 bar minimum, oil-free, 200-400 Nm³/h | Dew point -40°C or lower |
| Ambient Conditions | Temperature: 18-25°C, Humidity: 40-60% RH | Critical for dimensional stability |
FAQ: 4 hi Cold Rolling Mill Technical Questions
Q: What advantages does a 4 hi cold rolling mill offer compared to 2-high or 6-high configurations?
A: The 4 hi cold rolling mill provides an optimal balance between cost and performance for most precision rolling applications. Compared to 2-high mills, the four-high configuration allows for significantly smaller work rolls, which reduces rolling force requirements and enables production of thinner materials with better flatness control. Relative to 6-high mills (which add intermediate rolls), the 4-high design offers simpler mechanics, reduced maintenance requirements, and lower initial investment while still delivering excellent thickness control and surface quality for most applications up to 0.05mm thickness.
Q: How does the hydraulic AGC system maintain thickness accuracy during high-speed operation?
A: The hydraulic AGC system in our 4 hi cold rolling mill employs a multi-sensor approach to thickness control. Primary feedback comes from a non-contact thickness gauge (typically X-ray or isotopic) positioned immediately after the mill stand. This real-time measurement is combined with mathematical models predicting roll force and mill stretch. The control algorithm processes this information at rates exceeding 100 calculations per second, adjusting the hydraulic cylinder positions with sub-micron precision to maintain the target thickness despite variations in incoming material, temperature changes, or mechanical disturbances.
Q: What maintenance schedule is recommended for optimal 4 hi cold rolling mill performance?
A: We recommend a comprehensive maintenance program for your 4 hi cold rolling mill that includes daily visual inspections, weekly hydraulic system checks, monthly calibration of sensors and control systems, and quarterly comprehensive mechanical inspections. Critical components like roll neck bearings should be monitored continuously via vibration analysis systems. The hydraulic fluid should be sampled and analyzed quarterly, with complete replacement annually. Following these protocols typically results in 95%+ operational availability and extends the equipment service life beyond 20 years.
Q: Can the 4 hi cold rolling mill process materials with extreme hardness or high yield strength?
A: Yes, our 4 hi cold rolling mill can process materials with yield strengths up to 1800 MPa when properly configured. This requires specialized work roll materials (typically high-speed steel or tungsten carbide), increased roll force capacity, and modified roll profiles to prevent edge cracking. For such demanding applications, we recommend reduced reduction ratios per pass (typically 10-15% instead of standard 20-30%) and elevated rolling speeds to minimize dwell time and prevent work hardening issues. The mill’s computer control system contains material-specific rolling models that automatically adjust parameters based on the selected material grade.
Production Efficiency and ROI Considerations
The investment in a modern 4 hi cold rolling mill delivers compelling returns through multiple channels:
- Material Yield Improvement: Precision thickness control reduces over-rolling, typically saving 2-5% of expensive raw material costs
- Reduced Secondary Processing: Superior surface quality and flatness often eliminate the need for additional leveling or finishing operations
- Higher Production Rates: Modern 4 hi cold rolling mill installations achieve 25-40% higher throughput compared to older equipment of similar size
- Energy Efficiency: Optimized drive systems and regenerative power units reduce energy consumption by 15-30% compared to conventional mills
- Extended Roll Life: Properly controlled rolling parameters and roll bending systems extend work roll life by 20-40%, reducing tooling costs
A case study from a European specialty steel producer illustrates these benefits. After replacing their 30-year-old mill with a modern 4 hi cold rolling mill featuring hydraulic AGC, they achieved:
- 28% increase in production capacity for 0.1-0.5mm stainless steel strips
- 42% reduction in thickness variation complaints from customers
- 19% decrease in work roll consumption per ton of processed material
- 31% shorter setup times between different material grades
- Payback period of 2.7 years despite the significant capital investment
Conclusion and Technical Support
The 4 hi cold rolling mill with hydraulic AGC represents the optimal solution for manufacturers seeking to produce high-precision metal strips with exceptional consistency and surface quality. Its versatile configuration accommodates a wide range of materials from soft copper alloys to high-strength specialty steels, making it an ideal choice for operations requiring flexibility alongside precision.
When selecting a 4 hi cold rolling mill supplier, consider not only the equipment specifications but also the depth of technical support and application expertise available. HANI provides comprehensive commissioning support, operator training, and ongoing technical consultation to ensure your production goals are consistently met. Our engineering team includes metallurgists and rolling process specialists who can optimize mill parameters for your specific material requirements.
Whether you’re producing electrical steel for transformer cores, precision alloys for electronic connectors, or specialty stainless steels for medical applications, this 4 hi cold rolling mill delivers the performance, reliability, and precision required in today’s competitive manufacturing environment. Contact our technical sales team to discuss your specific application requirements and arrange for a detailed quotation tailored to your production needs.
For technical specifications, custom configuration options, or production consultation regarding our 4 hi cold rolling mill systems, please contact our engineering team today.
HANI is one of China’s leading professional cold rolling mill manufacturers, providing complete cold rolling systems to steel companies worldwide. HANI focuses on designing and manufacturing integrated cold rolling solutions that meet the industry’s highest standards of precision, efficiency, and durability. Our engineering expertise lies in providing turnkey cold rolling production lines to optimize the performance of modern steel manufacturing plants.
