Several points should be checked prior to laser shaft alignment in order to avoid problems later and to achieve good results:
- Foundation: A solid, rigid foundation is essential for a successful alignment.
- Machine Mobility: It is advisable to set both machines with about 80 mils of shims underneath the feet in case one machine needs to be lowered. Also, jacking bolts provide a safer and more accurate way to make horizontal moves.
- Rigid Couplings: Must be loosened to achieve accurate readings.
- Coupling Play: This can be avoided by turning the shafts a few degrees before starting measurements and then taking readings in the same direction.
- Bearing Play: Check for excessive bearing play.
- Soft Foot: Check for and correct soft foot before performing a final alignment.
Soft foot can severely affect the operating condition of a machine, and will undoubtedly shorten its life expectancy. Here are a few simple tips to help avoid soft foot in your machines:
- Eliminate rust, dirt, and any other contamination from the contact surfaces of the machine feet, shims or foundation.
- Avoid using more than four shims at a time under the machine foot. More than three shims can cause a spring effect.
- Eliminate undue external forces on the machine frame such as those from connected piping, conduit, auxiliary supports, etc.
- Use high-quality, clean, and uniform shims when shimming is necessary.
Alignment by Ana Maria Delgado, CRL