1. Abrasive solids and grit 
Wastewater and slurry applications commonly contain sand and grit that score seal faces. In municipal lift stations, excessive grit has caused seal leakage within months. Prevention includes selecting harder seal face materials (such as silicon carbide) and ensuring proper grit handling or pre-filtration. 

2. Dry running during startup 
Dry running is one of the fastest ways to destroy a Flygt pump seal. This often happens during improper commissioning or when fluid levels drop unexpectedly. Always verify submergence levels and use level controls or sensors to prevent dry starts. 

3. Incorrect seal material selection 
Chemical incompatibility between pumped media and seal materials leads to swelling, cracking, or corrosion. For example, industrial Flygt pumps handling oily wastewater require elastomers resistant to hydrocarbons. Material compatibility checks are essential, similar to best practices followed for ANSI pump components. 

4. Excessive vibration or misalignment 
Although Flygt pumps are submersible, vibration from worn bearings or improper installation can still damage seals. In one industrial sump application, ignoring vibration warnings resulted in repeated seal failures. Routine condition monitoring helps prevent this issue. 

5. Overheating due to cooling issues 
Flygt pump seals rely on surrounding fluid for cooling. Low-flow or intermittent operation can cause heat buildup, leading to seal face distortion. Ensuring correct duty cycles and avoiding operation outside design limits is key. 

6. Improper installation or handling 
Seal faces are precision-machined. Mishandling during installation—such as contamination or improper torque—can cause immediate failure. Following OEM procedures and using trained technicians is critical. 

7. Lack of preventive maintenance 
Waiting for leaks before addressing seal issues leads to secondary damage. Proactive inspections and scheduled seal replacement significantly extend pump life and reduce emergency downtime. 

Conclusion 

FAQs 

1. What is the most common cause of Flygt pump seal failure? 
Abrasive solids and grit are the leading cause in wastewater applications. 

2. Can Flygt pump seal failures damage the motor? 
Yes, seal failure can allow fluid ingress, leading to costly motor damage.

3. How often should Flygt pump seals be inspected? 
Inspection intervals depend on application severity, but annual checks are recommended. 

4. Are Flygt pump seal principles similar to ANSI pump seals? 
Yes, while designs differ, material selection and failure prevention principles are similar across ANSI pump components and submersible pumps.