Phase Analysis in Machine Fault Diagnosis

Diagnosing Unbalance

→ Static Unbalance

1X generated & both ends of the rotor are "In-Phase" in Radial Direction

→ Couple Unbalance

1X generated & both ends of the rotor are 180° "Out-of-Phase" in Radial Direction

→ Dynamic Unbalance

Phase in both ends of rotor should be somewhere between 0 and 180

→ Overhung Machines Unbalance

1X generated & both ends of the rotor are "In-Phase" in Axial Direction

→ Vertical Machines Unbalance

1X generated & phase reading along the machine are "In-Phase"

Diagnosing Misalignment

→ Angular Misalignment

1X, 2X, 3X generated & both ends of the rotor are "Out-of-Phase" in Axial Direction

1X, 2X generated & both ends of the rotor are "In-Phase" in Radial Direction

→ Parallel Misalignment

1X, 2X, 3X generated & both ends of the rotor are "Out-of-Phase" in Radial Direction

1X, 2X generated & both ends of the rotor are "Out-of-Phase" in Angular Direction

Diagnosing Eccentricity

→ Eccentric Sheaves/Gears

1X generated & both Horizontal and Vertical direction are "Out-of-Phase"

Diagnosing Bent Shaft

1X generated, both ends are 180 "Out-of-Phase"