Case Study
Anomaly Alert Averts Catastrophe
at a Tire Manufacturing Plant
1. Abstract
Calender roll plays an important part in tire production. It compresses the raw material into sheets which are used for tire building. Failure of the calender roll can halt the tire building process downstream leading to an enormous production loss.
This paper demonstrates how the malfunction of heat exchanger was detected
which avoided the seizure of the calender roll bearing.
which avoided the seizure of the calender roll bearing.
2. Introduction
Sensor nodes were mounted on the entire drivetrain i.e. Motor, Gearbox, and Roll Bearings
to monitor the condition of the calendering process. Refer to Figure 1 which shows the
sensor node mounted on calender roll’s Non-Drive End bearing.
Figure 1: Sensor Node Mounted on Calender Roll’s Non-Drive End Bearing
2.1. Background
2.2.1 Heat Exchanger System Construction
Water circulation type heat exchanger with a TCU (Temperature Control Unit) is used for
the calender roll to regulate the roll bearing’s temperature. Failure of this heat exchanger
system will result in increase of the bearing temperature. Refer Figure 2 which shows heat
exchanger of calender roll.
Figure 2: Heat Exchanger of Calender Roll
3. Sequence of Events
The sequence of event is as follows:
1. Bearing at the non-drive bearing on the calender roll began to overheat and reached temperature of 180 °F (82 °C) on December 16, at 8:20 PM, as a result of which an anomaly alert was instantly triggered.
Figure 3: Viewing Spike in Temperature Trend
Figure 4: Viewing Normal Temperature Trend
2. Taking note of the SMS, the shift engineer immediately inspected the calender roll bearing and found that the temperature shot up because the heat exchanger had stopped working.
3. The heat exchanger was subsequently powered up and within 30 minutes temperature came back to its normal level of 115 °F (46 °C).
4. Solution
Failure of the heat exchanger system is generally an unforeseen event and will not provide any prior mechanical symptoms. Anomaly Alert mechanism is specifically designed to address such circumstances. This mechanism will look at the present vibration and
temperature trends and compare it against the machine’s normal operating parameters. Machine’s anomalous behaviour, diverging from the benchmark, is captured and immediately notified to the user in the form of email and text messages.
5. Conclusion
Overheating due to an external factor such as the cooling system failure can potentially damage the bearing. Temperature spike in such cases is sudden, leading to immediate seizure of rolling motion. In the case of this calendar roll, a stoppage for an extended period of time would have led the plant to discard tons of processed rubber and incur high component replacement costs. More importantly, real-time anomaly notification and prompt response from the shift engineer saved 12 hours of production loss for this tire
manufacturing unit.
