A novel tool monitoring approach for diamond wire sawing
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2021-11-10 |
| Journal | Production Engineering |
| Authors | Berend Denkena, Benjamin Bergmann, Björn-Holger Rahner |
| Institutions | Leibniz University Hannover |
| Citations | 2 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Diamond Wire Sawing Tool Monitoring
Section titled âTechnical Documentation & Analysis: Diamond Wire Sawing Tool MonitoringâExecutive Summary
Section titled âExecutive SummaryâThis research presents a critical advancement in tool monitoring for mobile diamond wire sawing, addressing significant safety and productivity challenges inherent in high-speed cutting processes (e.g., nuclear dismantling, construction). 6CCVDâs high-performance MPCVD diamond materials are ideally suited to enhance the reliability and longevity of the cutting segments utilized in this methodology.
- Core Problem Solved: Eliminates the need for unreliable, intermittent manual inspection by providing robust, real-time, in-process monitoring of grinding segment displacement.
- Methodology: Utilizes non-contact inductive (eddy current) sensing, proven robust against harsh environmental conditions (water, mud, dust) and high abrasiveness.
- Material Compatibility: The monitoring approach was successfully verified across all three major diamond bonding matrices: sintered, vacuum-brazed, and galvanic.
- Performance Metrics: Achieved reliable detection of segment displacement using the time interval between two minima ($t_{min}$) feature, which demonstrated superior robustness compared to segment duration ($t_t$).
- Detection Threshold: Reliable detection of segment displacement was confirmed starting from 2 mm displacement at high wire velocities (up to 20 m/s).
- Safety & Productivity: The system enables real-time detection of tool failure (segment displacement and wire slip), significantly improving operator safety and maximizing machine uptime in critical applications.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the research paper detailing the operational parameters and monitoring performance:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Max Tool Velocity | 30 | m/s | Maximum relative movement speed cited for grinding process |
| Required Sampling Rate (f) | 15 | kHz | Nyquist-Shannon minimum estimate for $l_s = 4$ mm, $v_s = 30$ m/s |
| Actual Sensor Sampling Rate | 50 | kHz | Data acquisition rate used in experimental setup |
| Inductive Sensor Measuring Range | 4 | mm | Eddy current displacement sensor specification |
| Segment Length ($l_s$) (Tool 1) | 6.8 ± 0.37 | mm | Sintered bond matrix tool specification |
| Segment Distance ($l_i$) (Tool 2) | 19.0 ± 0.65 | mm | Vacuum-brazed tool specification |
| Minimum Detectable Displacement ($t_{min}$) | 2 | mm | Reliable detection threshold (moving wire, 20 m/s) |
| Standard Deviation of $t_{min}$ | 8.00 ± 8.14 | ms | Measured across sensor distances 0.5 mm to 2.0 mm |
| Wire Tension ($F_s$) | 1.000 | N | Used in stationary wire tests (Test Rig 1) |
| Dry Grinding Velocity ($v_s$) | 18 | m/s | Used for functional verification on S355JR steel |
Key Methodologies
Section titled âKey MethodologiesâThe experimental verification focused on establishing a robust, non-contact measurement principle suitable for harsh industrial environments:
- Measuring Principle Selection: An inductive (eddy current) displacement sensor was selected. This principle is robust against common contaminants (water, mud, dust) that interfere with optical or capacitive systems, and it is compatible with the metallic components (sleeve, bond matrix) of the grinding segments.
- Functional Verification (Stationary Wire): Initial tests were conducted on Test Rig 1 (stationary wire, moving sensor) to verify the signal curve across three different diamond bond matrices (sintered, vacuum-brazed, galvanic) and to determine the effective measuring range of the sensor on the diamond wire tool.
- Functional Verification (Moving Wire): Tests were transferred to Test Rig 2 (moving wire, stationary sensor) integrated into a CNC machine to simulate high-speed operation (up to 20 m/s) and real grinding processes (dry rope grinding of S355JR steel).
- Feature Generation: Two time-based features were developed to monitor segment displacement: segment duration ($t_t$) and time interval between two minima ($t_{min}$).
- Feature Selection: $t_{min}$ was determined to be the superior monitoring feature, exhibiting independence from sensor distance and a 22% lower standard deviation than $t_t$, enabling reliable detection of displacement from 2 mm.
- Monitoring Algorithm: The final approach utilizes two offset eddy current sensors and compares the actual $t_{min}$ value against a moving average within a tolerance band. This dual-sensor setup allows for the differentiation between segment displacement (both sensors deviate) and wire slip (results do not match).
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe successful implementation of high-speed diamond wire sawing relies fundamentally on the quality and thermal performance of the diamond segments. 6CCVD provides the advanced MPCVD diamond materials and customization services necessary to replicate, optimize, and extend this research into industrial deployment.
Applicable Materials
Section titled âApplicable MaterialsâThe paper highlights the necessity for diamond segments with sufficient thermal conductivity and chemical resistance to withstand high thermal stress and mechanical work. 6CCVD recommends the following MPCVD materials for next-generation wire sawing segments:
| 6CCVD Material | Recommended Grade | Application Rationale |
|---|---|---|
| Single Crystal Diamond (SCD) | Thermal Grade (High Purity) | Ideal for inserts requiring maximum thermal dissipation (high thermal conductivity) to minimize rubber coating wear and segment displacement caused by heat stress. |
| Polycrystalline Diamond (PCD) | High-Toughness Grade | Suitable for the abrasive bond matrix, offering superior fracture toughness and wear resistance in high-impact cutting environments (e.g., concrete, steel). |
| Boron-Doped Diamond (BDD) | Heavy Doping (Conductive) | Potential for advanced segments requiring integrated sensing capabilities or enhanced electrochemical stability within the metallic bond. |
Customization Potential
Section titled âCustomization PotentialâThe research utilized segments with specific diameters (e.g., 9.9 mm to 10.5 mm) and relied on metallic sleeves and bonding matrices (galvanic, vacuum-brazed). 6CCVDâs in-house capabilities directly support the manufacturing requirements of these advanced tools:
- Custom Dimensions: 6CCVD provides SCD and PCD plates/wafers up to 125 mm in diameter. We offer precision laser cutting and shaping services to produce custom diamond inserts or plates matching the exact segment length ($l_s$) and diameter ($d$) requirements cited in the research.
- Advanced Metalization: The integrity of the metallic bond is crucial. 6CCVD offers internal metalization services (Ti, W, Pt, Au, Pd, Cu), allowing engineers to specify optimized adhesion layers for enhanced bonding strength and thermal transfer between the diamond and the metallic sleeve, critical for both vacuum-brazed and sintered tools.
- Polishing and Surface Finish: We provide ultra-smooth polishing services (Ra < 1 nm for SCD, Ra < 5 nm for PCD) to ensure precise geometric alignment of diamond inserts, which is vital for maintaining the defined segment distance ($l_i$) and maximizing the accuracy of the inductive monitoring system.
Engineering Support
Section titled âEngineering SupportâThe successful implementation of this monitoring approach requires precise material selection to ensure tool longevity and consistent signal response. 6CCVDâs in-house PhD team specializes in material science for extreme environments. We offer consultation services to assist researchers and manufacturers in:
- Optimizing diamond material selection for specific high-stress grinding and sawing applications (e.g., nuclear decommissioning, rock extraction).
- Designing robust metalization schemes to maximize the lifespan of the diamond-to-metal bond, reducing the risk of premature segment displacement.
- Tailoring diamond thickness (SCD/PCD from 0.1 ”m to 500 ”m) and substrate dimensions (up to 10 mm) to meet the mechanical and thermal demands of high-velocity wire sawing.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.