Mechanical Seal Failure
Mechanical seal failure occurs when a rotating-equipment seal can no longer control leakage between a rotating shaft and stationary housing.
What this term means in maintenance
Mechanical seal failure occurs when a rotating-equipment seal can no longer control leakage between a rotating shaft and stationary housing.
Common causes
Mechanical seals may fail because of:
- Dry running
- Misalignment
- Shaft runout
- Vibration
- Incorrect installation
- Wrong material
- Contamination
- Poor flush
- Pressure or temperature
- Pipe strain
Practical example
A pump seal leaks repeatedly because pipe strain distorts the casing and alignment.
Evidence
Review leakage pattern, seal faces, elastomers, operating conditions, flush system, alignment, and installation.
Corrective action
Replacing the seal may restore operation, but the underlying operating or mechanical condition must be addressed.
Common mistake
Treating every seal leak as normal wear hides installation, piping, process, and reliability problems.
Related concepts
Related maintenance terms
Keep exploring connected CMMS, reliability, and maintenance planning terms.
Shaft Alignment
Shaft alignment is the adjustment of connected rotating-machine shafts so their centerlines operate within approved offset and angular tolerances.
Root Cause Analysis
Root cause analysis is a structured investigation used to identify the underlying conditions that allowed a failure or problem to occur and determine actions that reduce recurrence.
Rotating Equipment
Rotating equipment is machinery containing components that rotate to transfer energy, move material, or perform mechanical work.
Glossary FAQs
- What causes mechanical seal failure?
Dry running, misalignment, vibration, wrong material, poor installation, flush problems, pressure, temperature, and pipe strain.
- Is replacing the seal enough?
Only when the underlying cause has also been controlled.
- What evidence should be reviewed?
Seal faces, elastomers, leakage, alignment, operating conditions, flush system, and installation.