Customer: Municipal utilities of Rotenburg an der Fulda
The sewage treatment plant of the municipal utilities of Rotenburg an der Fulda is designed for a load of 34,000 inhabitants (size class 4) and serves around 20,000 people.
Pump failure in the final settling tank – costly and time-consuming!
Within one year, one of the three spiral pumps failed due to a design
flaw. At that point in time, only one mechanical defect was able to be
identified. Due to bearing damage, the gearbox was literally
torn apart and had to be completely replaced – a costly
and time-consuming affair.
Technical information on the system
- 70 – 80 l/s on average
- 280 l/s maximum
Clear data. Clear facts. Prevention through Condition Monitoring.
A Condition Monitoring system
consisting of a MELSEC System Q control unit from Mitsubishi Electric
and three FAG SmartCheck devices was used to help solve the problem in the return activated sludge pumping station. An FAG SmartCheck device was attached to each
of the three drives for this purpose. This system has been continuously monitoring the gearbox condition ever since
. In the event of changes in vibration,
the system provides data at an early stage about these deviations, which
can be the initial signs of possible damage.
Technical information on the solution
- Various rolling bearings
- Mitsubishi Electric MELSEC System Q
- eWon router type 4005CD
- Via WLAN
- Access point on mobile end devices reaches up to the control station, 300 m
- Up to several years of data history
- Information passed on via a control system to the control station
- Remote monitoring
Preventing failures through real-time monitoring
The project in Rotenburg shows a case in which a gear failed completely
four months after the first pre-alarm. The results show just how early on the
first alarm indicates the presence of a deviation. Immediately initiated preventive
maintenance measures counteract a potential total failure.
Based on specific malfunction reports, errors can be specifically
remedied without the entire gearbox needing to be completely disassembled to look for the
Storage, analysis, optimization
Preventing systematic failures
The microprocessor integrated into FAG SmartCheck stores all values in long-term memory.
They can be reviewed and analyzed later via the integrated
web server. The control system can pass on the data to
higher-level systems either directly or via remote control technology.
The solution can be used anywhere where wear can be caused by mechanical,
rotating parts or where changes can occur due to external
influences. In addition to wastewater, thick matter, liquid, vacuum,
and heat pumps, other tools can also prove to be useful, such as fans, ventilation units,
compressors, CNC machines, and centrifuges.