Custom Solutions
Dust Deflector Blades Extend Rotor Life
- Industry:
-
Iron ore pelletizing plant
Capacity of 4.1 million tpy per line, now increased to 4.6 million tpy per line
- Location:
- North Shore, Quebec, Canada
- Application:
- Hood Exhaust Fan Dust loading: 22 gr/ft3
Original Equipment Description and Rotor Life
The original fan, which had radial tip blades, was furnished by a competitor.
The rotor was removed from the casing requiring major repairs after only 18 to 24 months of operation. The repaired rotor was then used for another 18 to 24 month period after which it was no longer repairable and had to be scrapped. The original rotor has been replaced by other competitors using various wear protection without any significant improvement to the rotor life.
COVENT Rotor Specification
Model E60D-9950, equipped with slightly backward inclined, flat blades and chromium carbide hard surfacing of the same type and thickness as the original equipment.
The distinguishing feature is that the COVENT rotor is protected by custom designed dust deflector blades.
COVENT Equipment Behavior
The rotor was placed in service in September 1992.
After 24 months of operation, in September 1994, the dust deflector blades were replaced through the fan inspection doors without dismantling the fan or removing the rotor. The entire operation was done within a single 8 hour shift.
The dust deflector blades were replaced in this fashion every 18 to 24 months. The rotor was removed after 12 years of service requiring major repair however its structural integrity was still intact. The rotor has since been replaced by one of similar design which utilizes improved hard surfacing technology. All process fans at this installation have been replaced by COVENT rotors with slightly backward inclined, flat blades with dust deflectors and they have all experienced the same success. These process fans include the Updraft Drying Fan, the Windbox Exhaust Fan and the Windbox Recuperation Fan.
Conclusion
The COVENT rotor was in operation for 12 years (144 months) without any major repairs. This is an increase in rotor life by a factor of 6 to 8 when compared to the original equipment and other retrofits.
COVENT proprietary and proven dust deflector blades result in:
- Less maintenance time for rotor servicing
- Fewer shutdowns for rotor removal
- Reduction of production losses due to servicing and shutdowns
- Increased reliability and fan availability