Mechanical (Rotary) Common Questions -8

EPC-School 2012

M for Mechanical  

Topic - Balancing & Alignment

1. What is alignment?

2. Why is it important?

3. What are the different types of misalignment?

4. What are the different types of alignment techniques?

5. What are the different causes of misalignment?

6. What are the various techniques used for alignment in refineries?

7. What is dynamic balancing?

8. How do we rectify unbalance?

9. What are the symptoms of unbalance?

10. How is unbalance generated in unbalance?

Answers to Above Questions-

1. Alignment is the process of making two or more axes collinear

2. It is important as it affects the stability of the machine, decreases vibration

3. Angular misalignment, radial misalignment or a combination

4. Alignment using dial gauges, laser alignment

5. Machine/ driver softfoot, excessive nozzle loadings, coupling wear, bent shaft

6. 2 point dial gauge, 3 point dial gauge, laser alignment

7. The technique of identifying unequal mass distribution and correcting it, thereby reducing vibration while rotating the equipment is called dynamic balancing

8. By adding weight to counter unbalance or by removing material from area of unbalance on chosen balancing planes

9. Excessive noise, high vibration

10. Flow changes, uneven weight distribution due to manufacturing defect, erosion, deposits (flue etc)