Precision Application of Laser Distance Sensors in a Thermal Power Plant
1. Project Background: From Manual Inspection to Intelligent Diagnosis
In large thermal power plants, boilers are core assets whose safety and stability directly affect overall plant performance. During startup, shutdown, and continuous operation, boilers undergo thermal expansion and contraction caused by uneven heating. Boiler expansion displacement is a critical indicator reflecting this mechanical condition.
Traditional inspection methods—manual measurement with rulers and handwritten records—suffer from low data frequency, significant safety risks for personnel, and the inability to capture continuous and dynamic expansion trends. These limitations make it difficult to detect gradual abnormalities or provide early warnings of potential failures.
To address these challenges, the power plant introduced MyAntenna L3 laser distance sensors, deploying a three-dimensional online expansion monitoring system across 28 critical measurement points. The goal was to achieve real-time, high-precision monitoring of the boiler’s “mechanical vital signs” and fully transition toward predictive maintenance.
2. System Solution: Multidimensional Sensing and Application-Specific Engineering
2.1 Three-Dimensional Monitoring Architecture: From Single-Point Measurement to Global Insight
At each critical measurement point, three L3 laser distance sensors were installed and precisely aligned with reflective targets welded onto the boiler structure. Together, they formed a localized three-dimensional coordinate system (X, Y, Z axes).
By continuously capturing micrometer-level displacement in all three directions, the system provides a comprehensive picture of overall boiler expansion behavior and localized deformation. This multidimensional data enables advanced diagnostics of issues such as internal slagging, uneven combustion, and abnormal stress in supports and hangers—delivering an unprecedented level of insight.
2.2 Installation Strategies for Harsh Operating Environments
Boiler rooms in thermal power plants present harsh conditions, including high temperatures, heavy dust, and continuous vibration. To ensure stable long-term operation, the project team implemented tailored protection strategies:
- High-Temperature Mitigation
In boiler top areas where ambient temperatures reached up to 60 °C, wide-temperature sensor versions were customized. Additional external thermal insulation shields were installed by the customer to block radiant heat and ensure reliable operation within specified temperature ranges. - Dust Protection
In dust-intensive areas caused by coal handling and combustion, potting-filled sensor versions with IP67 protection were deployed. Standard sensors were also equipped with sealed dust covers to prevent coal dust from adhering to the optical lens, ensuring stable signal quality and measurement accuracy.
2.3 Stable and Reliable System Networking Architecture
The system adopts a distributed acquisition and centralized management architecture to ensure data integrity and communication reliability:
- Local Signal Acquisition and Conversion
At each monitoring point, the three sensors output 4–20 mA analog signals, which are connected to a local multi-channel signal acquisition unit. This unit integrates signal conditioning and protocol processing, converting multiple analog inputs into a single RS-485 digital signal. - Anti-Interference Data Transmission
RS-485 communication lines are connected using a parallel bus topology, significantly simplifying cabling while ensuring long-distance, interference-resistant data transmission in complex industrial environments.
3. Project Value and Results: Comprehensive Improvements in Safety, Efficiency, and Management
3.1 Unprecedented Safety Assurance
The system enables 24/7 continuous monitoring and automatic alarming. When expansion behavior deviates from normal patterns—such as restricted expansion, excessive contraction, or uneven deformation—multi-level alarms are triggered immediately. This allows maintenance teams to intervene before potential risks escalate into equipment failures, significantly enhancing boiler operational safety.
3.2 Dramatic Improvement in Maintenance Efficiency
The project eliminates hazardous and labor-intensive manual inspection tasks. Monitoring data is automatically uploaded, with historical trends and analytical reports generated in real time. Data collection and recording efficiency has increased by over 90%, allowing maintenance personnel to shift from field inspections to data-driven analysis and decision-making.
3.3 A Model for Industrial Digital Transformation
This project successfully demonstrates the adaptability and reliability of high-precision intelligent sensing technology in the harsh industrial environments of Northwest China. Its modular and standardized solution architecture enables rapid replication across industries such as power generation, chemical processing, and metallurgy—providing a practical and scalable reference for industrial digital transformation.
Learn More About MyAntenna
MyAntenna is a national high-tech enterprise specializing in the R&D, manufacturing, and sales of laser distance sensors and antenna solutions, certified under ISO 9001 quality management standards. Core products—including laser distance sensors and custom internal and external antennas—are widely used across power generation, building materials, chemical processing, and metallurgy industries, earning strong customer trust through proven performance and reliability.
If you are facing similar equipment monitoring challenges or seeking to advance the intelligence level of your production systems, MyAntenna’s professional team is ready to support your needs.