Shaft Alignment
Nizwa College of Technology
Shaft Alignment
Shaft alignment is the process to align two or more shafts with
each other to within a tolerated margin.
Shaft in Alignment
Types
•Parallel or Lateral misalignment
•Angular misalignment
•Combined Angular and Lateral misalignment
Combined Angular and
Parallel or Lateral misalignment
Angular misalignment
Lateral misalignment
Disadvantages of Misaligned shafts
• When shafts are misaligned, forces are generated.
• These forces are resulted in Vibration, noise, bearing
damage, shaft damage, coupling damage and
Looseness.
• In extreme cases the bending stresses applied to the
shaft will cause the shaft to fracture and break.
Shaft Aligning Techniques
• Shaft alignment by conventional method
• Shaft alignment by Dial Test Indicator (DTI)
• Shaft alignment by Using LASER Equipment
• Shaft alignment by using computer.
Shaft Aligning procedure
Preliminary Checks
Visually check coupling, pipe hangers, base bolts, coupling
spacing etc.
Check for coupling & shaft run out.
Sag Check
•
Clamp the brackets on a sturdy piece of pipe
•
Zero both indicators on top, and then rotate to the bottom.
•
The difference between the top and bottom reading is the sag
•
Each time alignment reading is taken then the sag must be
accounted for subtracting
Shaft alignment by Dial Test Indicator (DTI)
Horizontal Alignment (Parallel)
Pump
Motor
• Aligning the shaft's centerlines from side to side
• The indicators are zeroed on the left and read at the right
• Make sure that you always view the DTI from pump side
• There is no sag compensation on the horizontal move
• Record the indicator reading and move the motor to the required
distance for horizontal alignment.
Shaft alignment by Dial Test Indicator (DTI)
Vertical Alignment (Angular)
Pump
Motor
•The indicators are zeroed on the top and read at the bottom
•Record the indicator reading and consider the sag compensation by
subtracting it from the recorded reading
•Move the motor to the required distance for vertical alignment by
adding shims in place
•Tighten all bolts and take and check the readings
•If the readings are within tolerance than the equipment is aligned
Principle of Alignment (DTI)
Arrangement of DTI in Alignment
Vertical
Horizontal
(Parallel)
(Angular)
Shaft alignment by Using LASER Equipment
Lay out of Laser Alignment
Parallel or Lateral misalignment
Angular misalignment
Shaft alignment by Using LASER Equipment
Measuring head 1
Measuring head 2
Display unit
General lay out of LASER Alignment Technique
General Lay out
Laser beam on the
measuring head
Alignment procedure (LASER)
Vertical Alignment
Alignment procedure (LASER)
Horizontal Alignment
Alignment procedure
Aligning Motor to Pump
LASER Aligning Display Unit
Reading Shows Angular &
Parallel Deviation
Aligning of Equipments
Aligning Engine to Alternator
Aligning Motor to gear box