Development and Industrial Verification of High Wear-Resistant Overlay-Free Cement Roller Mill Alloy Sleeve

Literature Overview

This study published in China Casting Equipment and Technology (2026, Vol. 61, No. 2, pp. 96–99) by Li Baoshi, Guo Huaxiu, Dong Liang, and Wang Guoju presents a significant engineering innovation in cement roller mill sleeve manufacturing. The research was conducted by Xingtai Roller Special-Shaped Roller Co., Ltd. and the State Key Laboratory of Roller Composite Materials. The work addresses a persistent industry problem: traditional cement roller mill sleeves require frequent overlay repair, resulting in short service life and high maintenance costs.

Technical Innovation

Three-Layer Composite Sleeve Design

The innovation introduces a novel three-layer composite structure:

This design eliminates the need for overlay welding entirely, replacing a repair-intensive approach with a monolithic cast solution.

Novel Manufacturing Process

Two key process innovations are coupled for the first time:

1. Turbulent chills casting centrifugal casting: Creates a specific solidification pattern that refines the outer layer microstructure through controlled turbulence during solidification.
2. Differential temperature heat treatment: Applies non-uniform thermal profiles across the sleeve cross-section to optimize the hardness-toughness gradient from surface to core.

Applied to Ø1800 mm × 1700 mm sleeve specification

This represents a large-scale industrial application, demonstrating the scalability of the technology.

Performance Results

Microstructural Improvements

The refinement of MC (M₆C-type) carbides from 28.7 μm to 22.1 μm represents a critical improvement in wear resistance, as finer carbides provide more uniform resistance to abrasive attack and reduce stress concentration points that initiate wear damage.

Service Performance

Process Engineering Analysis

Turbulent Chills Centrifugal Casting

The turbulent chills technique introduces controlled turbulence into the molten metal during centrifugal casting, which:

1. Disrupts the normal dendritic growth pattern
2. Promotes equiaxed grain formation in the outer layer
3. Enhances the uniform distribution of vanadium carbides
4. Creates a finer, more homogeneous microstructure

This is fundamentally different from conventional centrifugal casting where the outer layer tends to develop columnar grains with coarser carbide morphology.

Differential Temperature Heat Treatment

The differential temperature approach applies different cooling rates or thermal profiles to different regions of the sleeve:

• Outer layer: Faster cooling to maximize hardness and carbide refinement
• Transition zone: Moderate cooling to develop toughness for stress buffering
• Core: Slower cooling to maintain ductility and structural integrity

This creates an optimized hardness-toughness gradient that outperforms both uniform heat treatment and conventional overlay approaches.

Engineering Practice Implications

Cost-Benefit Analysis

The 46% reduction in per-ton cement cost from roller wear represents substantial savings for cement plants operating multiple roller mills. For a typical cement plant with 4–8 roller mills operating 8000+ hours per year, the annual savings can be significant.

Maintenance Schedule Impact

The 36-month overlay-free period fundamentally changes the maintenance paradigm:

• Traditional approach: Overlay repair every 3–6 months, requiring mill shutdown, surface preparation, welding, post-weld heat treatment, and quality inspection
• New approach: Sleeve replacement only when wear exceeds dimensional limits, potentially extending to 12–18 months of continuous operation

Quality Control Considerations

For implementation, the following quality control measures are essential:

1. Casting quality: 100% ultrasonic testing of the core for internal defects
2. Microstructure verification: Metallographic examination of the outer layer for MC carbide size and distribution
3. Hardness profiling: Cross-sectional hardness mapping to verify the designed gradient
4. Dimensional accuracy: Coordinate measuring machine verification of sleeve geometry
5. Service monitoring: Periodic thickness measurement and wear rate tracking during initial deployment

Study Insights and Strategic Value

This research represents a paradigm shift in cement roller mill sleeve manufacturing—moving from a repair-intensive overlay approach to a design-integrated wear-resistant casting solution. The 6.42× improvement in relative wear resistance is remarkable and has been validated through 3000 days of continuous industrial operation, providing confidence in the technology's reliability.

The key insight is that the combination of turbulent chills casting and differential temperature heat treatment creates synergistic effects that neither process alone could achieve. The turbulent chills refine the as-cast microstructure, while the differential temperature treatment optimizes the mechanical properties through controlled transformation of the retained austenite and carbide morphology.

For the cement industry, this technology offers a path toward more sustainable grinding operations by reducing energy consumption per ton of cement produced (due to longer sleeve life maintaining optimal grinding geometry) and reducing maintenance-related emissions from overlay welding operations. The technology has already been deployed in major domestic and international cement group production lines, demonstrating commercial viability and scalability.