The document provides step-by-step instructions for properly aligning rotating equipment using dial gauges. It discusses key concepts like identifying and correcting for soft foot, pipe strain, thermal growth, and sag in alignment clamps. The document outlines the reverse periphery alignment method using dial gauges to measure and correct for parallel and angular misalignment. It provides examples of misaligned conditions and how to interpret dial gauge readings to determine the necessary shim corrections. Quizzes are included to test the reader's understanding of applying this alignment method.

1. Pii
Learning
t
ROTATING
EQUIPMENT

2. Pii
Learning
MOTOR
PUMP
Dial Gauge 1
Dial Gauge 2
Pipe strain
Off-set
TIR / 2
Thermal
growth
Step by step Alignment lessons,
starting from the basics,
Not by confusing write-up,
or by mere words, but by
Models and Visuals
a programme by
a well experienced
Rotating equipment
engineer.

3. Pii
Learning Types of flexible couplings
• Which of the following couplings you have?
• Of them which are close couplings and which have spool
piece?
•Chain Coupling
•Diaphragm Coupling
•Elastomeric Coupling
•Flexible Disk Coupling
•Flexible Link Coupling
•Gear Coupling
•Leaf Spring
•Metallic Grid Coupling
•Pin Drive Coupling
Spool
Close

4. Pii
Learning
The need for proper Alignment
Misalignment causes undesirable effects like:
• High vibration
• Joint leaks
• Internal rubbing
• Cracks
• Coupling failure
• Bearing failures
• Mechanical Seal failures
• Oil seal failures
How do you align your equipment in your company?
• Straight edge?
• Use Dial gauge?
• With dial gauge reading, how do you proceed?
• Trial and error?
• Mathematical formula?
• Graphical method?
• Electronic gadgets, like Calculator or Laser?

5. Pii
Learning How shafts get mis-aligned?
MOTOR
PUMP
Parallel Misalignment
PUMP MOTOR
Angular Misalignment

6. Pii
Learning
MOTOR
PUMP
In reality, on any equipment, both parallel & angular
misalignment exists. Why?
• Improper foundation, base-plate.
• Imperfect pump, motor dimensions.
• Improper pipe support.
• Thermal expansion of pipe line affects
alignment.
• Defective concrete base or support.
• Loose or broken foundation bolts.
• Soft foot.
• Shim related problems (loose, rusty, painted,
etc)
+
Unclear
knowledge on
proper alignment
practice.

7. Pii
Learning
MOTOR
PUMP
MOTOR
PUMP
Close Coupling
Spool Piece / Spacer

8. Pii
Learning
Using Straight edge (Scale) and Feeler gauge or taper
gauge.
• Make faces of coupling parallel. (Remove angular
misalignment)
• Then, make the flanges on one line.(Remove parallel
misalignment) How?
DRIVEN
MOTOR
Close Coupling Alignment
for Low speed drives
(1,500 rpm and less)

9. Pii
Learning
Insert feeler gauge at top and at bottom. Record the gap.
If gap not equal, then the faces are not parallel.
Case 1: Top more gap. Remove shim from front foot or add
shim at back foot.
Case 2: Bottom more gap: Remove shim from back foot or
add shim at front foot.
Now the faces will be parallel, but not the center lines.
MOTOR
How to remove angular
misalignment
Front foot Back foot
Feeler gauge

10. Pii
Learning
Case1: Gap, Top more,
bottom less.
Case2: Gap, Bottom more,
top less.
After adjusting the faces parallel, both the couplings need
not be at the same level.
More
More
Less
Less
M
M
P P
P
M P M
Up Up
Dn Dn

11. Pii
Learning
Case1: Remove shim from motor or add shim to pump.
Case2: Remove shim from pump or add shim to motor.
P
M P M
Case1 Case2
How much shims to add or remove?
Straight edge
Using a feeler gauge
measure the gap
Add or remove shim equal to the gap.

12. Pii
Learning
Review 1 - Straight edge method.
Step 1: Remove angular misalignment.
Step 2: Remove parallel misalignment.
Why so?
How to remove angular misalignment?
How to remove parallel misalignment?
While removing parallel misalignment, on a particular
equipment, you need to remove shims at the back foot
of motor, But there is no shims at that foot. What can
be done?
Can dial gauge be used for a better result?
What is dial gauge?

13. Pii
Learning
1. Pushing dial gauge
stem / plunger will show a
+ve reading.
2. Releasing the stem
will show a -ve reading.
3. Dial can be rotated.
+
+
-
-
OUT
Dial
Needle /
Pointer
DIAL
GAUGE
IN
Stem /
Plunger

14. Pii
Learning
Rim and Face Method.
MOTOR
PUMP
Dial Gauge
Radial
Dial Gauge
Axial
Dial gauges can be
used for close
coupling, if adequate
space available for
fixing gauges.
If the coupling has
spool piece, the axial
gauge can
be fixed if spool is
removed.
MOTOR
PUMP
Dial Gauge 1
Dial Gauge 2

15. Pii
Learning
Limitations:
• Needs space for fixing axial dial.
• Having taken readings, correction need to be
calculated, using similar triangles geometry.
• Excess end float will lead to erroneous reading.
Reverse Periphery Alignment method does not have
these limitations
MOTOR
PUMP
Dial Gauge 1
Dial Gauge 2
Rim and Face
Method.

16. Pii
Learning
Reverse Periphery Alignment method
• Set the clamps as shown.
• Always keep the pump - dial at the top & motor - dial
at the bottom position.
MOTOR
PUMP
Dial Gauge 1
Dial Gauge 2

17. Pii
Learning
The following are two typical misaligned conditions.
Which do you consider is the better?
Case1: Coupling
faces are not
parallel, but shaft
center lines are
collinear.
Case2: Coupling
faces are parallel, but
shaft center line are
not on one line.
Note: Rotating both couplings together while taking
reading will ensure best alignment, even though faces
are not parallel.

18. Pii
Learning
If driver’s center line and driven’s center line
are in one line, then the dial gauge readings will
be zero all around
Reading = 0
Reading = 0

19. Pii
Learning
If driver center line and driven center line are not in one
line then, the dial gauge readings will not be zero all
around
Off-set
+ 0.3
0.0
+ 0.2
+ 0.5 + 0.2
+ 0.5
+ 0.3
0
12
3
6
9

20. Pii
Learning
If there is only vertical misalignment, then the Offset is
equal to half of TIR ( Total Indicator Reading )
+ 0.25
0.0
+ 0.25
+ 0.5 + 0.25
+ 0.25
Off-set
TIR = + 0.5
12
3
6
9
TIR / 2
+0.25

21. Pii
Learning
0
+ 0.5
+ 0.3
PUMP
COUPLING
0
+ 0.2
MOTOR
COUPLING
- 0.7
- 0.4 - 0.3
STEP1:
• Set the clamps as shown.
• Always keep the pump - dial at the
top & motor - dial at the bottom
position.
• Adjust both the gauges to Zero.
• Take a set of dial gauge readings.
# Remember to set zero at the top for pump &
zero at the bottom for motor.

22. Pii
Learning
+ 0.5
+ 0.3
PUMP
COUPLING
0
+ 0.2
MOTOR
COUPLING
- 0.7
- 0.4 - 0.3
0
Let us understand what does these reading mean.
Horizontal addition has to be equal to Vertical addition.
H: (+ 0.3) + (+ 0.2) = + 0.5
V: ( 0 ) + (+ 0.5) = + 0.5
H: (-0.4) + (-0.3) = -0.7
V: (-0.7) + ( 0 ) = -0.7
Note: If sum of horizontal readings are not equal to vertical
readings, some thing is wrong, may be the dial gauge or the
alignment clamp.

23. Pii
Learning Following are two sets of readings, in which pump
readings are OK, but motor readings are not correct.
+ 0.5
+ 0.3
PUMP
COUPLING
0
+ 0.3
MOTOR
COUPLING
- 0.7
- 0.4 + 0.2
0
(+0.3) + (+0.3) = +0.6
is approximately equal to
( 0 ) + (+0.5) = +0.5
(-0.4) + (+0.2) = -0.2
is not equal to
(-0.7) + ( 0 ) = -0.7

24. Pii
Learning
• Set the alignment clamps such that the dial gauges
read the rims of the couplings.
• Always keep the pump dial gauge at the top and the
motor dial gauge at the bottom position.
• Adjust both dial gauges to zero.
• Rotate both the flanges together along with their dial
gauges through 360 degree.
• Note down the readings at 12, 3, 6 and 9 o’ clock
positions.
• If the sum of horizontal readings are not equal to
vertical readings suspect erroneous dial gauges or
improper clamping system.
• Now we have two sets of dial gauge readings.
REVIEW

25. Pii
Learning
QUIZ - 1
• In a dial gauge, pressing the plunger will show a -ve reading -True
or False ?
• Releasing the plunger will show a -ve reading - True or False ?
• Are these readings Right or Wrong ?
0
-0.5 -0.7
-1.2 0
+1.0 +0.3
+0.4
0
-1.4 +0.7
-0.8
• Fill in the blanks:
0
-0.6 -0.8
? 0
? +0.7
-2.6 ?
-0.6 +0.4
-0.5

26. Pii
Learning
PUMP
D 1 D 2
a
b
c
F1 F2
D1: Dial Gauge 1
D2: Dial Gauge 2
F1: Motor Front
foot
F2: Motor Back
foot
STEP: 2- Measure the distances: a,b, & c., using a measuring tape.
a= (D1 to D2), b= (D1 to F1), & c = (D1 to F2)

27. Pii
Learning
D 1 D 2
a
b
c
F1 F2
Graph Sheet
Zero Line
Datum
D1 D2 F1 F2
0
STEP:3-
Take a Graph sheet.
• Mark a datum line at 0
• Take suitable scale for ‘a, b, & c and
transfer these distances to the graph.
eg:
a = 24cm
b = 56cm
c =102cm

28. Pii
Learning
+0.5/2=+0.25
Offset
0
+0.7
0
+0.5
Pump
D1
Motor
D2
D1 D2 F1 F2
0
+0.7/2=+0.35
Offset
Here is a set of readings: D1=+0.5, D2=+0.7.
Divide D1/2 & D2/2
Let D1/2= Y1, D2/2= Y2
Mark this Y1 on line D1
and Y2 on line D2
Why to divide
by 2 !?
Remember
TIR/2 = Offset

29. Pii
Learning
D1 D2 F1 F2
0
Y1 Y2 H1 H2
• Now we have marked Y1 on line D1 and Y2 on line D1.
• Next, join Y1 and Y2 and produce until this new line Intersects F1
and F2.
• Measure H1 and H2.
• Remove Shims equivalent to H1 and H2 at motor feet.
• Depending upon Y1 and Y2, +ve or -ve, H1, and H2 will also be +ve
or -ve.
• If H1 and H2 are -ve equivalent shims are to be added.
In our example H1 &
H2 are +ve, hence
0.48 mm shims at foot
F1 & 0.67mm shims at
F2 are to be removed
for making alignment
corrections.

30. Pii
Learning
Quiz - 2: In following four figures, guess the required corrections.
D1 D2 F1 F2
0
Y1 Y2 H1 H2
D1 D2 F1 F2
0
Y1 Y2 H1 H2
D1 D2 F1 F2
0
Y1 Y2 H1 H2
D1 D2 F1 F2
0
Y1 Y2 H1 H2
Fig1: F1- add/remove
F2- add/remove
Fig2: F1- add/remove
F2- add/remove
Fig4: F1- add/remove
F2- add/remove
Fig3: F1- add/remove
F2- add/remove

31. Pii
Learning
Quiz 3 - Draw graphs for the following 3 sets of dial gauge
readings.
PUMP
D 1
D 2
a
b
c
F1 F2
a = 24 cm
b = 56 cm
c = 102 cm
D1
PUMP
D2
MOTOR
0
0
+0.4
-0.3
Case 1: +0.4 -0.3
Case 2: -1.2 -0.8
Case 3: +2.4 +1.6
D1 D2

32. Pii
Learning Side correction (Horizontal misalignment)
• After correcting vertical mis-
alignment, the final step is to
correct horizontal
misalignment.
• You can either use graphical method
or proper judgement.
• Graphical method is similar to
vertical correction procedure. The
gauges are to be set at left and right,
instead of at top and bottom.
• Alternately, side correction can be easily corrected by judgement.
• Keeping the gauges in position, adjust the side jack bolts such that
the dial gauge readings gradually reduces to half of the existing.
• Finally secure the holding down bolts using the proper torque.
0
0
+0.3
-0.5
D1 D2
D1
D2
Top view

33. Pii
Learning
Having familiarized with alignment method, we
shall now look at some important requirements
for starting alignment.
• Soft foot
• Pipe strain
• Thermal growth
• Sag of alignment clamps
• Dial gauge errors
Preconditions for alignment:

34. Pii
Learning
PUMP
Unlike tripod, in
four legged objects
like motor all the legs
may not touch the floor
uniformly.
Some times there could
be a gap under one of
its legs. This particular
leg is called Soft foot
D 1 D 2
F1 F2
Soft foot
How to identify the existence of Soft foot ?
Keeping the dial gauges in position, loose the motor holding down
bolts one by one. If soft foot exists under a foot, while loosening
you will notice a huge variation in dial gauge reading !

35. Pii
Learning Pipe strain
How to identify the existence of Pipe strain ?
Keeping the dial gauges in position, debolt the suction flange,
then the discharge flange. If the dial gauge indicate a huge variation,
then pipe strain exists. Re-adjust the pipe supports such that the
tightening of the flanges will not cause a huge variation in dial gauge
reading.

36. Pii
Learning
Thermal growth
Alignment is done in
cold condition. Some hot
equipment will grow under
operation.
A quick reading
immediately after shutting
down such equipment will
reveal the existence of
Thermal growth.
For such hot equipment
Thermal growth
compensation has to be
considered.

37. Pii
Learning
If sag exists, even if driver and driven are in one line, the
dial gauge readings will not show zero all around.
Hence, the clamping system must be strong enough, if
DBSE is more, say 200 mm and above.
DBSE
Too much
Sag
Sag
SAG: If DBSE-Distance Between Shaft Ends- is more, the
alignment clamp would bend because of the weight of dial
gauge. This bending is called Sag.

38. Pii
Learning
Dial gauge error:
Do you remember the following discussion?
Horizontal addition has to be equal to Vertical addition.
+ 0.6
+ 0.3
PUMP
COUPLING
0
+ 0.2
MOTOR
COUPLING
- 0.7
+ 0.6 - 0.3
0
H: (+ 0.3) + (+ 0.2) = + 0.5
V: ( 0 ) + (+ 0.6) = + 0.6
H: (+0.6) + (-0.3) = ?
V: (-0.7) + ( 0 ) = -0.7
Note: If sum of horizontal readings are not equal to vertical
readings, some thing is wrong, may be the dial gauge or the
alignment clamp.

39. Pii
Learning
Advanced Graphical solutions.1: Adjusting driver / driven.
Steps:
• Fix the clamps, set the dials.
• Important note:
• Set both gauges to zero at
bottom and rotate together
to the top position.
• Note D1 and D2.
• Measure the distances
between a,b,c,d,e,and f.
• Take a graph sheet and
transfer these points
a,b,c,d,e, and f, using a
suitable scale.
• Mark one half of D1 on line
c, half of D2 on line d. +ve
reading at top and -ve
reading at bottom.
a b c d e f
D1 D2
a b c d e f
Zero
Datum

40. Pii
Learning
a b c d e f
D1 D2
Example:
D1 D2
0 0
+14 +12
MOTOR
PUMP
+14/2
= +7
+12/2
= +6
y1
y2
• D1/ 2=y1, D2/ 2= y2
• Mark y1 on line c
• Mark y2 on line d
• Join c and y2, then
extend
• Join d and y1, then
extend
• With this graph
innumerous moves are
possible!
c d
y1 y2
HOW?

41. Pii
Learning
In this example let us discuss three (or more) possible corrections:
• Motor can be brought down, by removing shims under motor.
• Pump can be brought down, by removing shims under pump.
• With out altering out-board feet of motor and pump, add shims at in-
board feet of motor and pump, as shown by the dotted line.
• Can you think of some more possible adjustments?
c d
y1 y2
Add Add

42. Pii
Learning
Advanced Graphical solutions. 2:
Equipment with long spool piece -Cooling tower motor / gear box.
a b c d e f g h
45 15 45 135 45 50 65
D1 D2
a b c d e f g h
MOTOR
GEAR
BOX
LONG
SPOOL
• Transfer the points a,b,c,d,e,f,g, and h to the graph
using a suitable scale.
• Set both dial
gauges at
bottom.
• Adjust them
to zero.
• Rotate to top
position.
• Note D1 and
D2.

43. Pii
Learning
• In this example D1 (TIR) = -50, and D2 = -40.: D1/2= y1, D2/2= y2.
• Mark y1 on line C , and y2 on line F. (points where clamps is
fixed on hubs)
• Join y1 and d, then extend, join y2 and e, then extend.
• Now you have numerous options to align, move motor or gear
box or the both!
a c d
b e
f
g h
0 0
-50 -40
D1 D2
-50/2
= -25
-40/2
= -20
y1 y2
Zero
Datum

44. Pii
Learning
MOTOR
PUMP
Dial Gauge 1
Radial (Rim)
Dial Gauge 2
Axial (Face)
Rim and Face Method,
- by calculation.
• If driven equipment can not be rotated, Rim and face method
may be applied.
• Mount the dial gauges as indicated, one touching the face and
the other touching the rim.
• Rotate the motor coupling along with the dial gauges and ensure
the gauge stems touches all around.

45. Pii
Learning
- ve reading
Zero
P M P M
Zero
+ ve reading
Let us first understand axial misalignment.
Case: 1- Open at top Case: 2- Close at top
• Set zero at bottom
• Rotate 180
• Top -ve reading means, top
is more open than bottom.
• To make the faces parallel
motor has to be shimmed
up.
• Set zero at bottom
• Rotate 180
• Top +ve reading means, top
is more close than bottom.
• To make the faces parallel,
shims are to be removed.

46. Pii
Learning
How much shims are to be removed or added to make
faces parallel
Note:
•If Df is -ve
add shims.
•If Df is +ve
remove shims.
Zero
M
A
a
b
Df
F1 F2
F1 = + Df / A * a F2 = + Df / A * b If Df shows +ve reading
(Shims to be added)
F1 = - Df / A * a F2 = - Df / A * b If Df shows -ve reading
(Shims to be removed)

47. Pii
Learning
How much shims are to be removed or added to
remove radial misalignment.
Note:
•If Df is -ve
add shims.
•If Df is +ve
remove
shims.
F1 = + Dr F2 = + Dr Add shims if Dr shows +ve reading
F1 = - Dr F2 = - Dr Remove shims if Dr shows -ve reading
Understanding radial correction is fairly simpler, unlike axial.
It is direct addition or removal of what the radial dial gauge (Dr),
indicates
Zero
A
a
b
Dr
F1 F2

48. Pii
Learning
Now, what is the combined correction of axial &
radial misalignment ?
Note:
•If Df is -ve
add shims.
•If Df is +ve
remove
shims.
F1 = + Df / A * a + Dr F2 = + Df / A * b + Dr
Note: The assessment of + has to be done very carefully. If the axial
gauges are mounted on the back side of coupling flanges because of
non-availability of coupling gap, then further care has to be excised.
Zero
A
a
b
Dr
F1 F2
Df
Zero