Laser Alignment Guide

Why Laser Alignment?

Laser alignment tools use a laser beam and detector to measure shaft misalignment with precision far exceeding dial indicators. The system calculates the exact shim adjustments and lateral moves needed to bring the shafts into alignment.

Benefits: faster than dial indicators, more accurate, eliminates calculation errors, provides a permanent record, easy for less experienced technicians to use correctly.

Step-by-Step Procedure

1. Mount the laser unit on one shaft and the detector on the other. Ensure mounting brackets are clean and secure.
2. Enter the machine dimensions as prompted: distance between feet, coupling to front foot, coupling to rear foot, etc.
3. Rotate the shafts together through at least three positions (typically 9, 12, and 3 o'clock). The system measures misalignment at each position.
4. The system displays the current misalignment (angular and parallel) and the required corrections: shims to add/remove at front and rear feet, and lateral movement needed.
5. Add or remove shims as indicated. Use stainless steel shims of the correct thickness.
6. Move the motor laterally as indicated. Use jack bolts if fitted, or tap gently with a soft mallet.
7. Re-measure. Repeat the cycle until both angular and parallel misalignment are within tolerance.
8. Tighten all hold-down bolts and re-check. Tightening can shift the motor.
9. Save the alignment report for the maintenance record.

Common Mistakes

• Soft foot not corrected: If one motor foot is not contacting the baseplate, tightening the bolt distorts the motor frame, giving false readings. Always correct soft foot before aligning.
• Pipe strain: If the piping is forcing the pump out of position, the alignment will be wrong once pipes are reconnected. Always check for pipe strain.
• Not checking hot alignment: Cold alignment changes as the system heats up. Verify alignment at operating temperature, especially for hot service pumps.
• Dirty mounting surfaces: Rust, paint, or dirt on the shaft or mounting brackets gives false readings. Clean all surfaces before mounting.
• Rotating only one shaft: Both shafts must be rotated together. Rotating only one gives incorrect readings because the coupling flex is included in the measurement.