Due to their compact structure and efficient heat transfer, spiral heat exchangers are widely used in the chemical, energy, and other fields. Regular inspections are crucial to ensure long-term, stable operation. The following is the core inspection process:
1. Appearance and Foundation Inspection
First, inspect the equipment's exterior for signs of corrosion, deformation, or leaks, focusing on welds, pipe connections, and flange connections. Also, verify that the foundation is secure and that the anchor bolts are loose to prevent vibration from exacerbating wear during operation.
2. Pressure Testing
Tightness is verified through water or air pressure testing. A water pressure test at 1.25 times the design pressure is typically used, with no pressure drop after 30 minutes. An airtightness test uses an inert gas such as nitrogen, along with a leak detector or sensor to detect minor leaks.
3. Heat Transfer Performance Evaluation
Measure the temperature, pressure, and flow rate of the inlet and outlet media, calculate the actual heat transfer coefficient, and compare it to the design value. An abnormally high temperature differential or a sudden drop in flow rate may indicate reduced efficiency due to scaling, blockage, or damage to internal components.
4. Internal Structure Inspection
After removing the head, visually inspect the spiral plates for deformation, perforations, or deposits. Use an ultrasonic thickness gauge to measure the extent of plate thinning, paying particular attention to corrosion in areas of fluid flow. Also, check the integrity of the spacers and seals, replacing any deteriorated components as necessary.
5. Operating Parameter Monitoring
While the equipment is operating, use a vibration analyzer to detect abnormal vibration frequencies to determine if there are imbalances or friction issues. Infrared thermal imaging can help locate localized overheating areas and prevent potential failures.
6. Reporting and Maintenance Recommendations
Finally, the inspection data is summarized and a detailed report is issued, clarifying the corrosion rate, remaining service life, and repair priorities. For scaling issues, regular chemical cleaning is recommended. Frequently leaking areas require optimized welding processes or upgraded sealing materials.
A standardized inspection process can effectively extend the service life of spiral heat exchangers and ensure the efficiency and safety of production systems.
