Regular inspection of your digestion rotor helps maintain safe operation, reliable performance, and consistent analytical results. For ETHOS rotors such as SK-15, MAXI-24 HP, and MAXI-44, some components should be checked periodically and replaced when signs of wear, damage, or deterioration appear.
The following recommendations provide a practical reference for monitoring the condition of the rotor and its consumable components. The indicated service life is an average and may vary significantly depending on sample type and digestion conditions, including temperature, pressure, and run duration.
Rotor body and segments
Inspect the rotor body and segments visually every three months.
Look for:
- Physical deterioration
- Deformation
- Visible damage that could affect correct rotor assembly or operation
Under typical operating conditions, the average service life is approximately 24 to 36 months. However, replacement should always be based on the actual condition of the components rather than on time alone.
PTFE-TFM components
PTFE-TFM vessels and related components should be checked once a week.
A replacement may be required when:
- Blank values become unusually high
- Carry-over is detected
- Intensive cleaning is repeatedly necessary
- Damage has occurred following a strong reaction
- The component shows signs of deformation or physical deterioration
In addition to a visual inspection, monitor blank and carry-over values as part of your routine quality-control procedures.
As a general reference, PTFE-TFM components may require replacement after approximately 800 to 1,000 runs, or at least once per year, depending on operating conditions.
Safety shields
Visually inspect the safety shields once a week, paying particular attention to both the inner and outer surfaces.
Replace a safety shield when you notice:
- Physical deterioration
- Cracks on the inner or outer walls
- Shield material transferred or deposited onto the PTFE vessel
- Any other visible structural damage
The typical service life is approximately 1,200 to 1,500 runs, or 18 to 24 months.
Safety springs
Safety springs should also be visually inspected once a week.
Check carefully for:
- Signs of corrosion
- Physical damage
- Deformation or loss of integrity
The average replacement interval is approximately 800 to 1,000 runs, or once per year.
A simple routine that protects your workflow
Recording the number of digestion runs and including rotor inspections in your laboratory maintenance schedule can make it easier to identify gradual wear before it affects performance.
The recommended intervals are general guidelines. Aggressive samples, high-pressure applications, frequent operation, and demanding digestion conditions may shorten the service life of individual components.
When damage or abnormal wear is identified, do not rely only on the estimated lifetime. Replace the affected component and contact your Milestone representative or Technical Support whenever you are uncertain about its condition.
