Zhuojin Pipe Fitting Co., LtdApplication Status and Development Prospects of Wear-Resistant Surfacing Materials in the Cement Industry
Literature Overview
This review article published in China Surface Engineering (2009, Vol. 22, No. 5) by Wei Jianjun and colleagues from Zhengzhou Machinery Research Institute provides a comprehensive survey of wear-resistant surfacing technology applications in cement industry equipment. The work examines the operating conditions, failure modes, and surfacing solutions for critical cement machinery components including grinding rollers, vertical mill rollers, mill plates, crusher hammers, and hammer discs.
Operating Conditions and Failure Analysis of Cement Equipment
Equipment-Specific Wear Environments
The study systematically characterizes the tribological conditions for each equipment category:
| Equipment Component | Primary Wear Mechanism | Abrasive Material | Operating Conditions |
|---|---|---|---|
| Squeeze rollers | Abrasive wear | Limestone, clay | Moderate pressure, continuous contact |
| Vertical mill rollers | Abrasive + adhesive wear | Cement clinker | High pressure, high temperature |
| Mill plates (grinding discs) | Abrasive wear | Raw meal, clinker | Impact + sliding |
| Crusher hammers | Impact-abrasive wear | Hard rock fragments | High impact velocity |
| Hammer discs | Abrasive + impact wear | Mixed materials | Rotational + impact loading |
Failure Modes
The predominant failure modes identified are:
- Progressive material loss leading to dimensional deviation
- Surface fatigue and spalling under cyclic loading
- Adhesive wear causing material transfer between contacting surfaces
- Thermal cracking from frictional heat generation
Surfacing Materials and Process Technologies
Material Systems Employed
The review categorizes the wear-resistant surfacing materials into several families:
| Material System | Typical Composition | Hardness (HV) | Applicable Equipment |
|---|---|---|---|
| High carbon martensitic | C 2.5-3.5%, Cr 8-12% | 600-800 | Squeeze rollers, mill plates |
| High chromium cast iron type | Cr 20-28%, C 2.5-3.5% | 800-1000 | Vertical mill rollers |
| Cobalt-based alloy | Co 50-60%, Cr 20-30% | 400-600 | High-temperature applications |
| Carbide composite | WC, Cr7C3 reinforced | 800-1200 | Impact-abrasive conditions |
| Ceramic composite | TiC, TiN, SiC particles | 1000-1500 | Severe abrasive wear |
Manufacturing and Remanufacturing Approaches
The article distinguishes between two application strategies:
- Composite manufacturing: Surfacing applied during original equipment manufacture to extend service life from the outset. This approach is preferred for high-value components where the initial investment in surfacing is justified by dramatic life extension.
- Remanufacturing: Surfacing applied to worn or failed components to restore dimensions and performance. This strategy is particularly economical for large components such as vertical mill rollers and mill plates, where recycling the base material is more sustainable than complete replacement.
Economic and Environmental Benefits
The study highlights significant benefits from implementing wear-resistant surfacing technology in cement production:
- Service life extension of 2 to 10 times compared to uncoated components
- Reduced unplanned downtime and maintenance frequency
- Decreased raw material consumption through improved grinding efficiency
- Lower energy consumption per ton of cement produced
- Reduced waste generation from premature component replacement
Development Directions and Future Outlook
The authors identify three primary development directions:
- Expansion of application scope: Extending surfacing technology to additional cement equipment components currently not treated, such as conveyor components, classifier internals, and kiln refractory interfaces.
- Wear mechanism research: Deeper understanding of the interaction between abrasive particle characteristics, material microstructure, and failure modes to enable rational material selection for specific service conditions.
- Balanced property development: Simultaneous optimization of wear resistance and crack resistance, recognizing that extremely hard materials often suffer from poor fracture toughness and are susceptible to spalling under impact loading.
Engineering Practice Integration
For piping engineers and equipment specialists working in cement plants, this review provides a valuable reference for:
- Selecting appropriate surfacing materials for specific equipment wear conditions
- Planning preventive maintenance schedules based on expected surfacing life
- Evaluating the cost-benefit ratio of surfacing versus component replacement
- Designing surfacing specifications that account for thermal cycling and impact loading
The remanufacturing approach described aligns well with current sustainability objectives in heavy industry, offering a pathway to reduce material waste while maintaining equipment reliability.
Study Insights and Implications
This review represents a mature assessment of surfacing technology in a specific industrial sector. The emphasis on balancing wear resistance with crack resistance is particularly relevant, as many field failures in cement equipment occur not from gradual wear but from sudden spalling of brittle overlay materials. Engineers should always consider the full spectrum of loading conditions—including thermal cycling, impact events, and fatigue—when specifying surfacing materials rather than optimizing solely for hardness. The systematic approach to matching material systems with specific wear mechanisms provides a template applicable to other industrial sectors where heavy-duty wear-resistant overlays are required.