Zhuojin Pipe Fitting Co., LtdWear-Resistant Composite Lining Plates for Hot Continuous Rolling Mill Frames
Literature Overview
The research by Fu Hanguang and Huang Zhaojun (2004), published in Special Steel, presents the development and application of wear-resistant composite lining plates for hot continuous rolling mill frames. The study addresses a significant industrial challenge: extending the service life of rolling mill frames that are subjected to severe wear conditions during hot steel processing operations.
Core Technical Content
Problem Background
Hot continuous rolling mill frames are subjected to extreme operating conditions including:
- High temperatures from hot steel products (up to 1200°C)
- Mechanical abrasion from scale, oxide, and metal particles
- Impact loading from rolling forces
- Thermal cycling causing fatigue
- Chemical attack from scale and mill scale
Conventional frame materials suffer from rapid wear, requiring frequent maintenance and replacement that disrupts production schedules and increases operational costs.
Composite Plate Development
The research developed a composite lining plate through explosion welding technology, combining a structural substrate with a wear-resistant overlay:
| Component | Material Specification | Function |
|---|---|---|
| Base plate | 16Mn steel, 10 mm thick | Structural support |
| Base composition | 0.15-0.20% C, 0.8-1.5% Mn | Ductility and toughness |
| Overlay plate | Wear-resistant steel | Abrasion resistance |
| Overlay composition | 0.6-1.0% C, 0.5-1.0% Si, 0.8-1.2% Mn, 0.5-1.5% Cr, 0.4-0.6% Ni, 0.4-0.8% Mo, 0.0005-0.0015% B, 0.005-0.010% Y, 0.008-0.015% K, 0.008-0.015% Na | High hardness and wear resistance |
| Joining method | Explosion welding | Strong metallurgical bond |
Performance Characteristics
The composite lining plates demonstrated superior performance compared to conventional solutions:
| Performance Metric | Composite Plate | Conventional Surface Treatment | Rolled Composite |
|---|---|---|---|
| Surface hardness | HRC 60 | HRC 45-50 | HRC 55 |
| Shear strength | 340 MPa | 250-300 MPa | 300-350 MPa |
| Wear after 8 months | <0.2 mm | 0.5-1.0 mm | 0.3-0.5 mm |
| Service life | 8+ months | 3-4 months | 5-6 months |
Explosion Welding Process
The explosion welding process used to join the base and overlay plates involves:
- Precise alignment of base and overlay plates
- Controlled detonation of explosive charges
- High-velocity collision of plates (typically 200-500 m/s)
- Formation of a metallurgical bond through plastic deformation
- Creation of a characteristic wavy interface that enhances bond strength
The explosion welding process produces a bond strength that exceeds the strength of the weaker parent material, ensuring reliable performance under severe operating conditions.
Engineering Practice Implications
Application Design Considerations
For implementing composite lining plates in rolling mill applications, the following design considerations are important:
- Thermal expansion matching: The base and overlay materials must have compatible thermal expansion coefficients to prevent delamination during thermal cycling
- Stress relief: Post-welding stress relief is required to minimize residual stresses from the explosion welding process
- Surface preparation: Proper surface preparation of both base and overlay plates is critical for achieving consistent bond quality
- Installation tolerances: Precise dimensional tolerances are required for proper fit-up and installation
- Inspection protocols: Non-destructive testing methods must be used to verify bond integrity before service
Quality Control Requirements
The fabrication and installation of composite lining plates requires rigorous quality control:
| Inspection Method | Purpose | Acceptance Criteria |
|---|---|---|
| Shear test | Bond strength verification | ≥340 MPa |
| Hardness testing | Overlay hardness confirmation | HRC 58-62 |
| Visual inspection | Surface quality | No cracks, porosity, or delamination |
| Ultrasonic testing | Bond integrity | No indications of separation |
| Dimensional inspection | Size and shape verification | Within ±0.5 mm tolerance |
Economic Analysis
The implementation of composite lining plates provides significant economic benefits:
- Extended service life reduces replacement frequency by 2-3 times
- Reduced maintenance downtime increases production availability
- Lower replacement costs offset the higher initial material cost
- Improved operational reliability reduces unplanned shutdown costs
Study Insights
This research demonstrates the effectiveness of explosion welding technology for creating high-performance wear-resistant composite materials in industrial applications. The combination of a ductile base material with a hard, wear-resistant overlay provides an optimal balance of structural integrity and surface durability.
The successful application of composite lining plates in hot rolling mill frames represents a significant advancement in industrial wear protection technology. The performance improvements achieved—particularly the reduction of wear to less than 0.2 mm after 8 months of service—demonstrate the substantial benefits of this approach.
For engineers involved in steel pipe manufacturing and related heavy industry applications, this research highlights the potential of composite materials and advanced joining technologies for addressing wear challenges. The explosion welding process, while initially developed for specialized applications, offers a viable solution for creating custom composite materials tailored to specific wear conditions.
The research also underscores the importance of materials science in industrial equipment design. The careful selection of overlay composition, incorporating elements such as chromium, nickel, molybdenum, and rare earth elements, demonstrates how alloy design can be optimized for specific performance requirements. This approach to materials engineering provides a framework for developing other specialized composite materials for demanding industrial applications.