2 minute read
Hazardous Areas
Vibration monitoring could have saved thousands
Engineering service provider Quartzelec, a specialist in the offshore sector, explains how it repaired a critical motor fan on a floating production storage and offloading vessel and how, with preventative maintenance in place, the issue may never have occurred.
Despite the floating production storage and offloading (FPSO) vessel being just three years old, it had already experienced several equipment issues, with one significant failure related to the fan unit of a critical Ex de induction motor drive. When Quartzelec was approached to investigate the issue, it helped rectify the immediate problem and identified and addressed the root cause, as well as suggesting a potential solution that could minimise the likelihood of similar issues occurring in the future.
Quartzelec’s initial inspections of the 67kW 690V Ex de, cage induction motor identified substantial damage, including failure of the DE and NDE bearings, multiple ATEX defects, a melted cooling fan due to bearing failure, core damage to the stator and rotor, plus significant winding damage.
The immediate solution was to secure and fit an identical direct replacement machine; sourced and reinstated into the casing by Quartzelec, with the new unit fully balanced and tested. For most suppliers, that would have been the end of the project, but the Quartzelec team was eager to identify the root cause of the problem. “Having been able to install an operational replacement machine, we quickly established that a lack of regular maintenance had caused the previous failure. This was brought about by the motor greasing points being impossible to reach when the machine was in service,” explained Seoras Shaw, Project Manager at Quartzelec Aberdeen.
“Rather than accepting that this failure could reoccur with the newly installed duplicate motor, we worked with both the client and the OEM to identify a viable solution. Accessible greasing facilities have now been installed on the unit to allow the bearings to be maintained as part of the regular maintenance schedule, and this should significantly increase the operational life of the machine and reduce future risk of failure.”
Despite being less than three years old, the failed machine was beyond salvaging. However, had a condition monitoring programme been implemented from the outset, such extensive damage and the resulting replacement and downtime costs could have been limited or even totally avoided.
Quartzelec has developed preventative maintenance solutions and offers both ongoing and scheduled condition monitoring along with a vibration monitoring service, all of which can help identify potential issues as, or even before, they develop. Remedial maintenance can then be scheduled before a failure occurs. In this instance, the fan unit was critical to plant operationswith its failure causing operational issues for the client and almost three months without a functioning unit.
“As identified by our expert engineers, the root cause of failure is often overlooked, but it is critical when offering a repair solution to prolong machine lifespan and ensure longevity,” added Paul Oliver, Quartzelec Aberdeen’s Business Unit Manager.
“In this instance, we could have realistically saved around £17,000, which the client had to spend on a new machine, and eliminated all the associated costs and additional equipment downtime.
“Quartzelec's simple to implement vibration monitoring service would have identified the initial, first stage bearing defects as they happened. Appropriate action would have cost around £4,000 for replacement components and the time required for the replacement, which could have been done as part of a scheduled maintenance programme in under a couple of weeks.”
