October 23, 2019
Bringing in technology to make everyday work safer
High Potential Incident
In February 2018 a high potential incident (HPI) occurred at ABB Motors and Generators Factory in Jüri, Estonia. One wind generator stator nearly fell off the rotational table, with a high risk of falling onto a worker next to the table. At the time of incident, the worker was facing away from the rotational table and couldn’t see the imminent danger. A serious accident was avoided thanks to the quick reaction of the colleagues nearby who ran to support the leaning stator.
Understanding the scale of the problem
Rotating tables are very common devices in the Jüri factory. They consist of 4 support rolls and a drive mechanism that turns these rolls. 13 tables in total are in use in Jüri factory. Stators are lifted onto rotating tables to allow them to be turned to the right position for workers to insert the coils. During that rotation one stator on 1st of February 2018 had gradually shifted to one side of the table, almost falling off.
ABB Motors and Generators Factory maintenance provider Quant Estonia took the challenge to engineer out the potential hazard by introducing a smarter technical solution, but still keeping the operation as simple as possible for workers. A solution with ultrasonic sensors was developed to detect the position of stator. In case the stator starts to shift off the table, automatic stop is applied. The sensors are mounted onto electric actuator rails to allow setup for different stator sizes. Besides the safety improvement, the whole table was overhauled, new safety lights were installed and a frequency converter was added to the drive system. Frequency converter allows smoother start and end of rotation, with the aim to provide better worker safety and to extend the mechanical life of drive train components.
The project was initiated in April 2018, the prototype table testing started in July 2018. After several rounds of trials and modifications the final solution was rolled out to all the 12 remaining tables from February to June 2019. Upgrading of a single table took about 2 weeks.
Safety in use
ABB Manufacturing Manager Dmitri Moltsanov noted that the new sensors had stopped stators shifting off the table multiple times since the upgrade. Additionally, he pointed out, that the new added safety functionality has not slowed down the daily production process for his team. Living the value of putting safety first and taking resolute action when potential hazards are detected not only protects the people working at the factory from harm, it also protects the assets and improves reliability of the production.
Commitment to safety
At Quant, safety comes first. As a company and individuals, we believe that every accident can be prevented, and we are committed to work systematically towards zero accidents. Building a culture around safety, where meetings start with safety briefs and discussions how to work in a safe way, is essential. Measuring lagging indicators (e.g. Total Incident Rate) as well as leading ones (e.g. number of Safety Preventive Actions) are other building blocks at the core of our strategy.
Stator critically shifted to the side of table
New control system
Ultrasonic sensors on actuator rails
24.08.2019, Quant Estonia on behalf of ABB Motors and Generators Factory