Pipeline water flow monitor for coal mines
1Key Takeaways
This document applies to the design, manufacture and inspection of flow monitoring instruments used to measure pipeline water volume underground in coal mines.
2Expert Interpretation
In-depth interpretation of the NB/T 11630-2024 standard for pipeline water flow monitors for coal mines, covering explosion-proof design, technical parameters, test methods and inspection rules. Analyze key indicators such as flow measurement range 0.05-180m³/h, error ±2%, and provide application specifications for intrinsically safe equipment in methane environments.
Analysis of the core technical requirements of the standard
| Technical dimensions | Requirements of this standard | Comparison with conventional industrial standards |
|---|---|---|
| Explosion-proof grade | Ex ib I Mb/Ex ia I Ma | Usually Ex d IIB |
| Flow measurement error | ≤±2% | Usually±3%~5% |
| Ambient temperature | -5℃~40℃ | Usually0℃~50℃ |
Detailed explanation of key technical indicators
The nominal diameter of the sensor of the pipeline water flow monitor for coal mines needs to be selected in the range of 15mm~150mm, and its core performance requirements include:
- Flow repeatability error ≤±1%
- Intrinsically safe terminal insulation resistance ≥10MΩ
- Enclosure protection grade ≥IP54
Key points of explosion-proof safety design
According to GB/T3836.1-2021 standard, special attention should be paid to explosion-proof design:
- The operating parameters of components shall not exceed 2/3 of the rated value
- The maximum surface temperature shall be ≤150℃
- The non-metallic housing shall pass the surface insulation resistance test
Implementation suggestions and precautions
Installation specification: The sensor should be installed in the middle of the straight pipe section, ensuring that the straight pipe section length is 10D in front and 5D in the back (D is the pipe diameter)
Maintenance cycle: It is recommended to perform insulation resistance test every 6 months and flow calibration every year