Cooling Tower Inspection

If you go up a cooling tower, its best to not go alone.

There are 6 cooling towers. Cooling Tower #1 is redudancy and Cooling Tower 6 had a blade that failed due to unbalance. So 4 cooling towers are in operations all the time.

We had a discussion to see whether we could get an IR image. Choy said it wasn’t possible because the rotating blades would block the motor.

The fan of this cooling tower likely rotates between 900 and 1800 RPM. My FLIR E95 operates at 30 Hz (30 frames per second). If the fan were running near 1200 RPM (20 revolutions per second), the camera would capture about 1.5 frames per revolution — enough to occasionally “see” the motor through the gaps, though with some blur and reflection.

To verify the fan’s speed, I used my iPhone camera set at 30 fps and observed the blade movement. Because the blades appeared to move slowly rather than blur or appear stationary, it indicated that the fan’s rotational speed was slower than the camera’s frame rate of 30 Hz (about 1,800 RPM). This confirmed that my thermal camera, which also operates at 30 Hz, would be able to capture thermal images of the motor behind the blades with reasonable clarity.

Next time I'll just use my iPhone to find out the approximate speed of the rotating equipment.

TOWER 2

T

TOWER 3

TOWER 4

TOWER 5

T4 looks like it has misalignment. Both gear box and motor bearings are hot.

Motor has a flexible couple and is connected to a right angle gear drive.