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Common alignment mistakes and counter tips

  1. Safety first. Make sure the equipment is locked out and tagged out before you start. You are ultimately responsible for your own safety.
  2. Do not waste time and money conducting an alignment on a unit that is already problematic. If the foundation, base and supports are bad, then your alignment will be wrong.
  3. Before you start the alignment process, check the driver for soft foot first. Check one foot at a time while the others remain bolted.
  4. Except in rare cases, always conduct the alignment with the coupling spacer removed or loose. Realize and understand that you are really doing a shaft alignment, not a coupling alignment.
  5. It’s recommended to match mark the coupling halves so they align and reassemble together.
  6. Rotate both shafts together and in the same direction that they rotate in the operation.
  7. Check for the proper distance between shafts prior to starting the alignment and watch for axial play that will corrupt the readings and, consequentially, the alignment.
  8. Do not use hammers without rubber coating.
  9. During the alignment process always move the driver.
  10. When using dial indicators, be aware of spanner bar sag, and know how to check and compensate for sag.
  11. Depending on what technique or equipment type you choose to conduct the alignment, be sure to check both shafts for runout.
  12. Dial indicator must be perpendicular to the surface they are touching.
  13. Make sure the dial indicator is actually touching the surface to be measured and that the travel length is not compromised.
  14. Do not expect alignment accuracy greater than the dial indicator accuracy.
  15. Measure your shims. Keep shims clean and free of burrs and imperfections.
  16. Never use more than four shims total (aka stack) per equipment foot and try to keep it to three or less. The more shims, the more spring and margin for error.
  17. Always use the same number and size of shims in both front feet and the same number and size in the rear feet. The front stack does not need to match the back and vice versa. Do not use a different number of shims (stack size) from side to side in an effort to roll the unit.
  18. When using washers, hold down bolts, use a strong washer material (grade 8) and watch the size (diameter). If the washer cups warps at all and you will have issues with holding the alignment.

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