Manual Chapter 5

Chapter
8-1
8
Application Information
Machinery Shaft Alignment – General Overview
Poor shaft alignment can cause the following problems:
• Bearing failure
• Shaft deflection fatigue
• Seal leakage and failure
• Coupling failure
• Internal heating
• High energy consumption
• Excessive vibrations (studies have shown that almost 50% of exces-
sive vibration in direct-coupled rotating equipment is due to mis-
alignment)
Proper machine alignment will result in:
• Less downtime (increased production)
• Increased bearing life
• Lower energy costs
• Increased coupling life
• Lower vibration (lower maintenance costs, even on surrounding
machinery)
A successful alignment job involves completing at least five major steps:
• Pre-job preparation and setup (considering items such as soft foot,
base integrity, pipe strain, documentation, and tolerances)
• Measurement of the amount and direction of misalignment
• Calculating corrective moves
• Actually moving the equipment within preset tolerances
8
Chapter 8 Page 1 Friday, January 26, 2001 10:34 AM