Overhaul of Two 90kW Centrifugal Fans

JJ Loughran were recently asked to attend site for a local power station and assess two 90Kw Centrifugal Fans. Our electrical engineering team attended site and checked the insulation resistance of both motors and found that the values recorded were below nominal levels which would not allow for the motors to safely operate.

The extract fans could not be repaired on site so one of our mechanical engineering teams was immediately dispatched to mechanically disconnect both fans from the duct work, crane out of position and load for overhaul back to our engineering workshop. Due to the critical nature of the power station initial inspection and removal was carried out same day.

Once in our workshop we carried out the following works: -

  1. Mechanically dismantled both motors into individual parts
  2. Electrically inspected each unit
  3. Checked mechanical dimensions on front & back endcaps to ensure these values were within machine tolerances
  4. Clean all individual parts
  5. Varnished and stoved stator of one motor (the second motor was beyond economic repair and required replacement)
  6. Dynamically balanced rotor
  7. Dynamically balanced extract fan blades
  8. Replace bearings with new SKF
  9. Reassemble & test ran motors
  10. Carry out vibration analysis post assembly
  11. Clean & respray units back to original OEM paint specification
  12. Deliver equipment back to site.
  13. Mechanically and electrically reinstall extract fans onsite, run and test.

JJ Loughran also recommended to the customer to fit 230VAC heaters in the motor windings. As the fans do not run constantly these heaters would be energised when the motor is not in use, ensuring dampness or condensation build up does not occur within the stators.

Feedback from Power Station General Manager

“Just wanted to thank you all for getting us sorted over the last week. The fan was switched on, on site on Monday, which was great considering the work that needed done since last week. Good job from the team at Loughran’s”

At JJ Loughran we believe in the importance of being able to not only supply new motors, gearboxes and drives but also to repair equipment back to original OEM standards when it is cost effective to do so. With state-of-the-art equipment including IRD balancing machines and advanced test equipment we can ensure all repairs are carried out to the highest standards.

It is not always cost effective to replace with new; which is why JJ Loughran’s in house and onsite repair and overhaul capabilities are critical in supporting our customers fully.

 

Date

December 4,2020

Category