🔧 Field Diaries: Episode 1

ventergavin7
Jun 18
2 min read

Updated: Jun 19

Welcome to the first entry in my new series, "Field Diaries" a behind the scenes look into some of the jobs I've worked on. From the unusual to the everyday. Each episode captures real world challenges, on the spot problem solving, and what it’s really like out in the field.

Let's get started:

The Situation:

I was called in by a client who was dealing with persistently high vibration levels on their Boiler Induced Draft (ID) Fan. Initially, they requested a dynamic balancing job, thinking the fan was out of balance. But once I inspected the motor and fan with an initial vibration data set while the equipment was running, something else stood out.

The Evidence:

The vibration spectrum revealed elevated amplitudes at 2x and 3x running speed frequencies, which are classic signs of shaft misalignment, not imbalance. I discussed the data with the client and recommended that we carry out a precision laser alignment procedure instead.

Turns out, the fan wasn’t out of balance — it just had commitment issues with its motor. Time to get that relationship back in alignment!

The Fix:

The results showed both vertical and horizontal parallel misalignment. I corrected the vertical plane by shimming the motor feet, then carefully adjusted the motor laterally to bring the shafts into proper alignment. After a few iterations, the alignment values were well within acceptable tolerances.

Lessons Learned:

This job was a great example of how crucial it is to interpret vibration data correctly. Elevated harmonics like 2x and 3x often get overlooked or misunderstood. By identifying the root cause early, we avoided unnecessary balancing and delivered a long term fix, not just a temporary patch.

The Result:

After completing the alignment, the fan’s vibration levels dropped significantly and are now well within acceptable limits. The client was pleased with the outcome, and even more so that we avoided an unnecessary balancing procedure.