Universal Dry Ice Blasting

Hydroelectric Generator Cleaning

Actions taken before cleaning

• Maintenance crew recorded insulation resistance (Megger test)

• Stator temperatures were recorded at various generator loads

• Scaffolding was constructed

• Covers were removed from Generator

• Generator surrounding area were covered in plastic

Cleaning of Generator

• Upper windings cleaned with CO2

• Lower windings cleaned with CO2

• Field Poles are cleaned with CO2

• Stator cleaned with CO2 (may require repositioning of rotor)

• Windings are hand wiped to remove any remaining dust and oil

• Generator inspected for oil leaks and damage

• Generator can be painted with 2 coats of Glyptal

• All plastic is removed and floors are cleaned

Note: Depending on the size and condition of the unit this process

will take 4-7 days to complete.

Floors and generator were covered in plastic sheeting

Lower windings covered with oil and dirt

Upper end of rotor and windings before cleaning

Oxygen monitor and warning sign in place. An additional monitor was worn by the nozzle operator.

Dry Ice is (-109.3 F) CO2 Pellets are accelerated at high velocity. Upon impact the solid CO2 pellet turns to gas that expand in volume nearly 800 times of the pellet instantly. This process causes Micro-Explosions that help assist removal of debris.

Stator before CO2 Blasting

Stator and air vents partially cleaned. The air vents were plugged with gummy oil and debris. Leaving no air flow to cool the generator

Properly cleaning the generator without removing the rotor saves companies so much money on time and man hours that it would take to disassemble and put the unit back together.

Stator and air vents after CO2 Blasting

Some areas did require a second blasting

View of stator after second blasting

Blasting Generator inspection windows with CO2

Each winding is hand wiped after blasting to remove any residual dust and debris

Upper windings after CO2 Blasting

Lower windings after CO2 Blasting

Upper end of generator after CO2 Blasting

Vacuuming out lose dirt and debris

Painted surfaces were cleaned and degreased by hand

Thorough inspection of the generator conducted after all clean up is finished

For additional information please contact:

Torie Fidler

Universal Dry Ice Blasting

760-525-8380

Email torie@universaldryiceblasting.com

Website http://universaldryiceblasting.com/