advanced alignment alberta module

8/19/2019 Advanced Alignment Alberta Module

http://slidepdf.com/reader/full/advanced-alignment-alberta-module 1/31

Millwright

1

60403a

88880006877

+01

MILLWRIGHT

16403A

3.0 AD

ilrilililtil

ilililil

il Illlil tl

0888800068778

$4.68

Advanced

Alignment

Machine

Levelling

Fourth

Period



Advanced

Alignment

Rationale

l4/hy is it

important

for

you

to leurn this skill?

Aligning

two or more machine shafts that

are coupled together is

a

very important

skill to

have in

the

millwright

trade. Thermal

growth

and

process

forces

from

flowing

media

tend

to misalign

aligned

machines

when they are started and

placed

under

load.

Using the

Essinger

procedure,

along

with

graphs,

calculations and design

d,ata, it

is

possible

to

misalign

a

machine when it is

cold and

not

running

so

that

it

runs aligned at operational

temperatures. The desired end result is to have

very little

maintenance caused

by

alignment

problems.

Outcome

Wlten

you

huve completed

this

module,

you

will

be

able to:

Align

and then

purposely misalign a multiple chain of

cold, non-rotating machines to

a

very high degree of

accuracy

so

that the

rr-rachines

are aligned when

running

and

loaded.

Objectives

1. Revierv

safety,

rim and face and cross

dial shaft alignment.

2.

Explain the various techniques used to measure machine thennal

and

process

movement.

3.

Demonstrate graphical

solutions

for

solving multi-machine

shaft alignment.

lntroduction

You

need

to develop the

skill

of analyzing

and

solving

machine

shaft

to

shaft alignment

problems.

Alignment

solutions are developed and applied by logical

thinking and by

follou,ing

the strict

guidelines

set out in the

shaft alignment modules.

The procedures

followed

(such

as rim and face,

cross-dialing

and reverse

dialing)

use dial

indicators

to

measure

the degree

of misalignment

over specific

distances

to

determine

the

required

corrective

moves through

the formulae

or the

graph

methods.

The initial

result is

a

set

or

a

train of machines

that are coupled together in nearly perfect

shaft alignment

when

they

are

not running.

When the machines

are

energized

and

put

online

a

number of

things

happen

that

result in

the shafts moving out of

their ideal alignment

planes. In

other

words, the shafts become

rnisaligned.

This misalignment

is detrimental to the

life

of the

machine.

Thermal

Growth

or Shrinkage

Two

factors

that cause

a

machine

to move off its centreline are

lhermal

grou,th

or

shrinkage

caused

by the

expansion and contraction

ofmetal due

to temperature

changes.

Significant

temperature

changes may

take

place

u'ithin

a

machine

after it is

started

and

1 6tt403ap3.0.docx

O

2007.

Her Majestv the

Queen

in

right

ofthe

Province

ofAlberta



placed

under load.

The

temperature

may rise

due

to friction

or

to hot

materials

such

as

steam

rnoving

through

the machine.

An

example

of thermal

shrinkage

occurs

on

centrifugal

pumps

made

of stainless

steel

and designed

to

circulate

very

cold

brines

or

thermal

antifreeze

fluids.

The

reduction

in

pump

tenrperature

when

the

pump

is

operated

causes

tlre tnetal to shrink.

The Inost

accurate

rnethod

of

determinitrg

the

thermal

growth

of

a

rnachine

is

to

directh'

measure the

growth from

a

fixed

daturn

point

using optical.

rnechanical

or laser

measuring

instruments.

Moment

of Force

Another

factor

that

can move

a machine

off

its

centreline

axis is

a moment

of

force.

A

moment

of

force pushes

against

a

machine

to

force

or displace

it

off

of its principal

axis

ofrotation.

such

as

the force

created

by

high-pressure

steam

entering

one side

ofaturbine

pushing

it sideways.

Using engineering

design

data and formulas.

it

is

possible

to

calculate

the

degree of misali-enmerrt

due

to therrnal

grouth

and nrornents

of

force.

Once

the amounts

of movement

of the machines

are

calculated it rnakes

sense to

perform

cold

corrective

trloves

that are opposite

to

(or

counteract)

the thentral

growth

and rnornents

of

force

tnovetlents. The required

cold

corrective rnoves

result

in rnachine

shafts

and

couplings

being

purposely

misaligned

when not operating.

As

the machine repositions

(frorrr

temperature change or moment

of

force).

you

want

the shafts

and couplings

to

move

into almost

perfect

alignment.

For this

intentional

misalignment

of

cold

rnachines

to be

successful

it is imperative

that

the machine

foundation is

sound.

A crack or fracture

in a critical

location

within

the

foundatiorr

could alter machine

shaft positions

due to foundation

shifts. These

shifts may

be caused

by'hydraulic pressures

or

seasonal

shifting

ofthe

subsoils

adjacent

to the

foundation.

A

cold,

purposely

misaligned

tlachine

alignment

can be

checked

by

predicting

the cold

su'eep

readings.

These

readings

are

taken from

cross

dial

aligment

graphs (vertical

and

horizontal).

If

the cold misaligned

sweep readings

from

the unit

match

the

predicted

readings

from

the graphs

it

is

safe

to

assume

that the machines

have been

successfully

misaligned.

At this

point

the machine

should

be started and placed

under normal

load. As

the

n.rachines

heat

up

they exhibit

a

lou'er

vibration level

as they

come into

alignment.

This

is

good.

but

u'hat

happens

if

the

vibration

levels

steadily

increase?

At

some

high

vibration

lirnits

it

is

advisable

to shut

the rnachine

down

before

it fails.

At

this

noint

it

rnal'

be necessary

to

perform

a

hot

aligrunent,

u'hich

lneans

to

inspect

the

aligrunent

just

after

the machine

has

been

shut dou,n.

The

hot

aligmnent

inspection

rnay

reveal

that

the

machines

did not move

in the

directions

that were

anticipated.

A

good

rnethod

of

hot

alignment inspection

is

the most reliable

industry

standard, rvhich

is

called

rhe

Essinger

Tooling

Ball

alignment procedure.

The

Essinger

method can

be

used

to check

and

track transient lrlovements

u'hile

the machines

are hot and running.

Transient movelnents

are

machine

lrovements

that

are

not

non.nal

or predictable.

Several

otlrer methods have been

developed

to

check hot

alignrr-rents.

One

basic method

is

called

hot machine

olignntent

in.sltection,

uhich

means

that the

inspection is

performed

on the

machine

as

quickly

as

possible

after the

machine is

shut

down. The

brackets

and

dials

are

mounted

and

a

set

of su,eep

readings

are

quickly,

taken.

These

sweep

readings

change

constantly

because

the

n-rachine

is

cooling

down.

t'0.l03ap3.0.docx

C

2007.

Her Majesn

lhe

Queen

in right

of the Province

o{'Alhena



Objective

One

Llthen

you

have completed this objective,you

will

be uhle

to:

Review safety,

rim and face and

cross dial shaft aligrunent.

Safety

Obtain a

safe work

pennit

and

n'ork

order,

then lock out

the equipment

that

is

to be

aligned and

make ceftain that an

information

tag

is

placed

on the

locked

out energy

panel.

On

some

higher

voltage

panels,

a

racking out or

electrical

disconnect

procedure

rnust

be

followed.

Racking out,

locking

out and tagging the control

or

source

panel prevents

personal

injury

due

to

an

unplanned, unwanted equipment start-up.

The tag should have the

following

information:

r

the reason for the

lockout.

r

the

date

and

e

the

narne

ofthe

person

responsible

for the

lockout.

Keep in mind that the

energy source is not always

electricilv; it may be

petroleurn

fuels

or stearn. In the

case

ofnatural

gas,

diesel or

gasoline powered

engines,

it is necessary

to

isolate or

disable

the unit so

it cannot

start

when it

is rolled

over during

aligrunent

checks.

Steam

lines

entering

a turbine

must be closed and

chained

or

locked in the

closed

position.

In

some cases, a

slip

blind

can be

installed after

the

valve.

In

an

industrial

complex that controls machine operation thlough the use of

proqrarnmable

logic controllers

(PLCs)

or

distributive control

(DC)

systerns.

it

may be

necessarv

to request the control roorn

operator

to disable

the unit. The operator may

also

issue

a

safe u'ork permit

that

requires

motor control centre

(MCC)

panel lockout

for

a

specific

machine. The last inspection

before starting

an

alignment

procedure

is

to try to

test-start

the unit being

worked

on at the local command station.

Care

must

be

taken

when

preparing

special

types

of

process

equiprnent

for shaft

alignment.

An

example of this u'ould be

a

steam turbine

driving a

dynamic colt'lpressor.

In this case,

both the turbirre

and

the colnpressor must

be blocked

in

(r'alves

closed),

isolated.

bled

off

and

locked. The

reason

for

compressor isolation

and

lockout

is to

prevent

a

reverse flow

of

gas

through

the

compressor, which would result in

the

unit

running

backwards

at

high

speeds.

Hydraulically

driven

equipment

must

be

isolated

and bled

off so that no shaft

rotation,

other than

alignment rotation, takes place.

The equipment

must

be

isolated

by

locking the

valves

in

a

closed

position

and

bleeding

off trapped oil

to the

reservoir. Accumulators

should be

depressurizedby

bleeding

the

high-pressure oil to

the

resen'oir. In

cases

where

large

presses

are

used, it rnay be necessary to block

with

wood to

prevent

drift

due

to

gravity.

The reverse

flow of oil

through

a

pump

can

result

in the

purnp turning

in

reverse

and driving an electric motor.

I 60403ap3.0.docx

G

2007, Her

Majes$

the

Queen

in right

ofthe

Province

ofAlbena



The procedure

to lock

out valves

on a turbine/corlpressor

unit is

shown

in Fieure

l.

Compressor

TurbinelCampressor

Clcse and

lock

sleam thrc{lle

valves

Compressor Valves

1, Close

all

compressor

nl^-^

-.^^^,,"^

^^J

tuJU

iJ,

g)>ul

u

d;

lu

lockoul

vaive actuaiof.

1500$

Ste

am Inlet

$team Supply Valves

Close all steam supply valves

and

chain

and lock hand wheels.

d:scharger.valves

2. Shul

ofiand

lock

oLtt

pcwer

3. Close

and

iack

out

hanC

wheels and chaln

Figure

I -

Valves to lockout

on turbine/compressor

unit.

(Photographed

at Agrium

Redwater

Fertilizer

Operations)

Pneumatic

motors

that require

shaft

alignment

must

also be isolated

and

locked

out. The

lines

to and frorn

the

motors must

be

depressurized

so

that

the

potential

for

an

accidental

start

is eliminated.

Coupling

guards

and

safety shields must

be reinstalled

after

the

alignment

is completed.

Guards prevent

accidents that

could

be caused

by

human

contact

with

rotating

shafts and

couplings. Shields

prevent

accidental burns from high heat

sources such

as

engine

exhaust pipes.

I 60-l0jap3

0

docr

C

2007.

Her Majeso.the

Queen

rn

right of the

province

of Albe(a

d*ry

ffii

--'

'.

sf,

Siearn Supply Valve

Hand \{heel



Objective

Two

ll/hen

1,ou

huve

completed

this

objective.

you

will

be

able

to:

Explain

the various

techniques

used

to

measure

machine

thermal

and

process

lrovement.

Spindle

Shaft (Drive Shaft) Goupling

Atignment

You

may

be

required

to

align

an externallv

mounted

electric

motor

to

an

internally

mounted

gear

drive

unit,

as in

the

case

of

a

cooling

torver

fan

drive

assembly.

One

way

to

do this

is

to

use

two dial

indicators;

one

mounted

on the

face

of the

inboard

coupling

at

the

12

o'clock position

and the

second dial

on the face

ofthe

outboard

coupling

at

the 12

o'clock position.

See

Figure

2 for

arrangement

of

the

dials.

Dial

lr

j

l

Caupling

a

I

Li(

I

L-..,

I

L:B

n

u;,

-

Rnr

=

90"

-

1trn

-

/tK,

-

4nr

Coupling

a

Coupling

x----n*

Figure

2 -

Cooling

fan

drive.

The

spindle

shaft

alignment

rnethod

is

used

to negate

the effects

of

bar

sag

over long

distances.

This

method

of

alignment

will

correct for

angular

and

offset

misalignment

in

both

the vertical

and

horizontal planes.

The

rnethod

works

on the

assurnption

that

all of

the

n.risalignment

is

angular

and

the correction

takes place at the

two coupling

centrelines.

The

amount

of angular

misalignrnent

is measured

at both

couplings and

then.

using

sirnilar

triangles.

is

projected

back to

the motor feet

u'here

the

calculated

shirn

move

is

added or

removed

from Sl

and

S: locations.

This

shim

move u'ill

then result

in

the motor

shaft

centreline

being

coaxial rvith

the

gearbox

shaft centreline.

Her

Majesn, the

Queen

in right

of the

Province

of Alberta



Use

the

following

steps to calculate

the

shim one

and two and

side

to

side moves.

Step

One

The following

is

a

solution

for

Sr

and S: using

"A"

dial readings

and

dirnensions.

S,

=

TIR\

Lre

De

L,^

S,

=:qx

TIRo

'

DA

S,

=

TIRA

L.^ D^

L"^

Sz

==axTIR^

DA

Step Two

Use

the

follorr,ing formula to

solve

for

S

1

and

32

using

"B"

dial

readings

and

dimensions.

S,

=

TIRB

L,- De

T .^

S,

=:]g^TIRB

'Du

S,

=

TIRB

Lru

DB

T

S,

=3xTIR'

DB

Step Three

Combine the

"A"

and

"B"

dial fbrrnulae solutions

by adding

the

"A"

and

"B"

dials

together

in

a

final formula.

II

S,

=

"tt

xTlR.

+

"rB

xTlR.

'

DA

-

Du

TI

S.

=

":t

vTlR.

-

-tu

xTIR^

-D.\*D"D

The

spindie

shaft

coupling

alignrnent method assumes

all of the rnisalignment

is angular

and will be corrected

at

the

flexible

coupling centrelines.

The

formula uses similar

triangles

to

determine the amount

of

shims required at

Sr

and 32 to bring

the

motor

shaft

centreline

into

alignment

with

the gearbox shaft centreline.

I 60.+03ap3.0.docx

O

2007. Her Malesq

the

Queen

in

right

of

the Province

of

Alberta



Using the

values from Figure

2:

^

60

ri

s,

=-x

)+:x-4=-24mils

'1010

^

90

15

5__x,)+_x 4='2lmrls

10

10

The

values for

S1

and

Sz

from

the combination

"A"

and

"B"

readings

are

the

required

shim moves.

A

positive

answer

means

that shims must be added;

a

negative

answer

means that shims must

be

removed.

A

positive

side-to-side move

means

that

the machine

should

be shimmed to the right-hand side by the value calculated. Always

view the

MTBS frorn

the

fixed rnachine

to determine the

left

and

right

sides.

The amount of

sag

on

the

"A"

and "B" dials

is minimal

as

they

are both

taking face-coupling readings.

Thermal Growth

Thermal

growth

describes small

movements that occur

in

all

types

of

industrial

equipment due to temperature

changes. The temperature

change

within a

machine

causes

the metal to

grow

or

shrink

by

a

fixed

amount that

is linked directly to the coefficient

of

expansion

for that specific metal

(see

Table

1).

Metal

Linear Expansion

per

Unit

Length

per'G

Linear Expansion

per

Unit

Length

per

"F

Aluminum 0.0000223 0.00001244

Brass

0.0000187 0.0000104

Bronze

0.0000'184

0.0000102

Carbon Steel 0.0000114

0.00000633

Cast lron

0.00001

18

0.00000655

Table

1

- Heat

expansion coefficients.

@ 2007, Her Majesq

the

Queen

rn ri,eht of the Province

of Alberta

I 60403ap3.0.docx



The formula

for

deterrnining

thermal

growlh

is the change in length is

equal to the

original length times

the change in temperature

times the coefficient of expansion

for that

parlicular

material.

AL:LoxATxa

Where:

AL:

change in length

(change

of centreline

height)

Lo

:

original length

(distance

from base to

shaft centreline)

AT

:

change

in

temperature

(average

temperature change)

u

:

coefficient ofexpansion

(obtained

from

chart)

Most

expansion

and contraction within machines is due to temperature changes. The

causes ofthese ternperature changes

depend upon the design ofthe machine.

Possible

causes of rise

in

temperature

include adding

heat from steam, heat from compression,

heat

from reaction,

heat

from electrical

load and

possibly

heat from friction

(or

the removal of

heat for the same

reason). Examples of cooler

temperature

machines are refrigeration

pumps,

brine

solution

circulation

pumps

and rl'it.rter

giycol

cooling tower

pumps.

You

must

be able

to

recognize and determine

thermal

growth

problems and be able

to

soive thern.

lf not recognized

and compensated

for, thermal

growth

can

result in shorter

machine life.

Thermal

gror.lth

affects machine

centrelines and therefore tends

to create misalignment

at

the couplings.

Example of

a

Thermal Growth Problem

Given an electric motor driving

a

brine

pump,

create

mathematical

solutions

for

thermal

growth

at

all

shim locations. Use

this information to

create

a

graphical

solution

to the

problem.

Use the values

given

in Figure

3.

.\

Ambient

Temperature

=72"7

Lr

:<

{

}r

L."

L,

I

x'

Figure

3 - Dimensions and

temperature

for

thermal

grou'th

brine

pump

alignment.

X=

10"

|

-

{arr

|

-

Alr

I

-4"

,'-

"^u

Elec{rlc

Molor

MTBS

Ca$on

$teel

-110"F

c

*1oo'r

o

-

so"F

€

r3o"

r

@

120'r

o

110"

r

g

Srine

Purnp

Carbcn Sleel

{*s0"F

s

3o'F

$-*

I

60-103ap3

0.docx

(

2n07. Her Majesn the

Queen

in right ofthe Pror rnce ofAlbena



NOTX

Assume that

the pump

and

motor

were perfectly

aligned when

cold

and not running.

The first

step is to determine

the amount

of thermal

growth

at the 4

shirnming

locations.

You

are

only

concerned

rvith

the thermal

expansion betrveen

the

base and

the

shaft

centreline.

Any expansion

above the shaft

centreline

will

not affect the

shaft alignment.

Tl.re

temperature

of the

components u,'ill

not

be

consistent

from

the

base

to the

shaft

centreline

so

an average

temperature is

required to

be able

to find the

average

thermal

groMh.

The more temperature

readings

that

can be

taken

at the

individual

shim locations

will

result

in a more

accurate

average; four readings is

usually adequate.

A

quick

approxirnation

can be obtained with

only.'

one

temperature reading

taken

at the shaft

centreline.

Add

this temperature to the

ambient temperature

and divide

by trvo. This will

result in

an average ternperature which

assumes that the

base

is at ambient

temperature.

The amount

of thermal

growth

can be calculated in metric

or imperial units,

but because

you usually

shirn

with

irnperial

shirn stock,

you

wiil

calculate the thermal

growth in

thousands

of an

inch

or rnils.

For convenience, round

to the nearest degree

ofternperature and round

to the nearest

thousandth of

an

inch for

shim illoves.

NOTE

You can

perform

these

calculations in metric

or in imperial.

but do not

mix

the

two

systems

when calculating

thermal growth.

Thermal

Growth

at

St

130

+

120

+110

+

90

Average temperature

:

=

I l2.5oF

Round

to

1

13'F

AL:LoxATxa

LL

:24"

x

(l

l3

-

72) x 0.00000633

:

0.006"

The shaft

centreline

will rise

6

rniis at

the S1

location.

Thermal

Growth at

Sz

110+100+90+80

Average telxperature

:

AL:LoxATxu

=

95oF

LL

:

24" x

(95

-

72)

x

0.00000633

:

0.003"

The

shaft centreiine

w'ill

rise

3

mils

at

the S. location.

I

60403ap3.0.docx

aq

2007.

Her Majesn rhe

Queen

in right

of

the

Provrnce of

Albena



Thermal

Growth at 33

9O

+'7)

Average temperature

=

81oF

AL:LoxATxa

LL:24

X

(81

-

72)

X

0.00000633

:0.001"

The shaft centreline

will

rise I mil

at

the S.

location.

Thermal

Growth at St

Averagetemperature

-

3'0

^72

=

5loF

2

AL:LoxATxo

LL

:

24

x

(51

-

72)

x

0.00000633

:

-0.003"

The

shaft

centreline

will shrink or

lower 3 mils at the Sa

location.

The

previous mathematical calculations

predict

the

thermal

growth

of

the

motor.

The

solution

indicates that

the shaft centreline

ra'iil rise up by 0.006"

at the S1 location

and

will rise up by 0.003"

at

the

52

location. Do not remove shims

at these

locations to

compensate

for thermal

grorvth. More information

is needed

before

starting any shirn

rnoves. The thermal changes

to the

purnp must

be

considered and compared to

the

electric

motor

growth

within a

graphical

representation of the

problem.

The

brine

pump

centreline thermal

growth

at the S:

location indicates

a

rise of 0.001" and

a

downward move of 0.003"

at

the

S+

location.

At

this

point.

all of the

necessary

information

is

available

and

requires

analyzing. Construct a

graphical

representation

of

the

problem

and then

analyze

it.

After

constructing the graph, study

it

and develop

some

conclusions

based on the

inforrnation contained

in

the

graph.

It is wise to leave the

pump

bolted

down because moving it could

result

in piping

strain.

Piping strain

is

the

cause

of unwanted distortion of the

pump

housing

due

to improper

pipe

fit-ups. As

the suction and discharge flanges

are

tightened, the

pipes pull

the

pump

housings

out of

shape and

alter the shaft centreline position,

disturbing alignment and

adding internal

stress

to internal rotating

parts.

This is not

good.

Once the

pipes

fit without

strain it is a

good

idea to leave

the

purnp

alone and make adjustments

on the

rnotor.

A

shim rnove under the motor feet is the best solution.

From the

graphical representation

in Figure

4,

one

solution

is

to

have the

/rol motor

centreline

#l and

the

hot

pump

centreline

#2 become one

and the same.

To

accornplish

this,

remove

0.001

" at both

S

1

locations and add

0.006"

shims at both

32 locations.

Keep

in

mind

that this solution

u'il1 only

work

if

the unit

u,as

precisely

aligned

when

cold.

In

other words, the

unit

had to be

precision

aligned

to

within

specs

before atternpting

to

offset the alignment

to compensate for thermal

growth.

Once the offset shim

moves

are

made

on

the

motor it

becomes necessarv to

oredict

u'.hat

the

"A"

and

"B"

dials

read

when

cold and offset.

IS

I 60+0Japj.0. docx

€

2007. Her Ma,iestl the

Queen

in right olthe Province of Alberta



11

C{

l,

T1

ll

il

ll

c0

\

tl

(/,r-=

Figure

4

-

Graph showing required shim move to

align motor to

pump.

160.403ap3.0.docx

O 2007. Her Majest) the

Queen

in right of the Province

of

Albena



NOTE

If

there is

no

sag

"A"

dial

cold should read

-12

mils

TIR

"B"

dial cold

should

read

7

mils

TIR

The

above

readings

for

"A"

and

"B"

dials

are

taken

from

where

line

nurrrber three crosses "A"

and

"B"

dial nlanes.

These

are

TIR

values.

Combination

Misalignment and Thermal

Growth

Correction

It is

possible

to align

a

unit

when

it

is cold and offset

for thermal

growth

by

rnaking only

one set

of

shim moves.

The data in Fisure 5 is used

in

the sample calculations.

Given:

Complete

the Thermal Offset Alignment.

,l

X= 15"

Top

+6

No

Bracket

Sag

Top

0

I e ,/

B\

L.U. , h. t \

t

urar

I

rr

\

unit

)

\3y_/

/T)

Re

\

utit

)

*'

\ggj-l

K.b.

+3

+10

Bottom

Bottom

Figure 5

- Data

given

for thermal

growth

example.

Electric

Motor

(cast

steel)

122',F

156'F

Gear

Box

(cast

iron)

140'F

140"

F

Base

Temp.

is72'F

12

l 60.l0lapl

tt

docr

(

1007. Her N'tajesn the

Queen

in ri-eht

olthe

Province

of Alberta



a at 4 :::::

:a

M:t:

Combination

Problem

Thermal growth

at 51

156

+ 7)

Average

ternperature

2

AL-LoxAtxa

LL:12"

x

(114

-72)x

0.00000633:0

003"

n

.,,

rnotor

t will rise

3

mils at

51

Thermal

growth

at

52

1)) t- 7)

Average

temperature

2

AL:LoxATxo,

AL

-

l2 x(97

-

72)

X

0.00000633:0.002"

rnotor

Q

will

rise 2 rnils

at S,

Thermal

growth

at 53

140

+

72

Averagetemperature-

)

=lU6"F

AL=LoxATxa

AL=

12 x

(106

-72)x

0.00000655:0.003"

The gearbox

Q will

rise

3

rnils at 53

Thermal

growth

at Sa

A'erage

remperarure

:

W

r =

|

o6oF

AL=LoxATxo

LL

=

12" x

(106

-

72) x

0.00000655

:

0.003"

-F

The

gearbox

shafl t

will

rise.i mils

at

Sr

O

2007, Her Ma;esq

the

Queen

in right

of rhr'Province

of

Albena

I 6it403ap3.0.docx



Analyze

the

graph

in

Figure

6 and

determine required

shim moves.

t/J--=

O

Lf)

z--:

O

O|r)

Nrr-r

U)r-=

Figure

6

-

Graph

shon,ing

required

shim

move

to align motor

to

gearbox.

\

c\l

u

U)

-i-

ll

:

f.*

ll

-

{(t")

-)[.C)[N]OrOr-

c)

o

-

l-l-:-:'

-,u

: :]

d]

\OE

\ 99

\,-r1--

\

cJt

'

to&-:

,

vE

--.98-

\c\

1

{Jt--

t'O$

-

-1

9N-

.'

tv[

\oN.

lal

l"

IX

i.Y

iCI

te

l'1-

L

:::]U

..i....:...:.i

x

-i-a-li

^

o

.c

J

l€

ln*

l*

E

o

6ii

(Jir

...i og.

\.2\

\6&

r:L>

,:,]...,

....izN,

lct

to\

lS4

i

':.

:.'...:..:$

i..i..:.r

r

"S

....tr \

:--i-:':

-, '-r f.--a-:-n-\-..

...1....i.-.

.'...'i...i.- l

-i.^i

.li-.i*ii-i--

i&

I-

:.N

I

d

r

-r

--

r^-l(-)

LO

tl

cv

C7:

'=

=\

-:.^

,-

c*

(,ll

5m

}

*f

i

_ ertt

-

t&l

\\

r.i f-

:il

F

ir,,..

\

{

4

tJt

lrl

tvl

ra ,

rn

i

E

a.

*.'T

*

l-J--t"r.i

s-i

_s

:*T

t4

I 60403api.0.docx

O

2007. Her Majestl

the

Queen

in right of the Province of Alberta



From

the

graph in Figure

6,

you

can see that

the

gearbox

raises

up

0.003"

at

the

53

and Sa

locations; leave

the

gearbox

bolted down. The hot gearbox

centreline is represented

by

line 2. Linel represents

the original cold rnisalignment

present

at

the

coupling. Line

3 is

the hot motor

centreline. In other words, the motor moved frorn

line

1

up to line

3

when it

was started and

loaded. Line

3 shows

a

fair

degree

of angular misalignment

of the hot

motor centreline

as

compared

to line

2,

which

represents

the hot gearbox centreline.

To correct this misaligrunent

of

the motor,

0.003" shim

removal

is required at

both S1

locations

and 0.001

inch

shim

addition

is

required

at

S:

locations.

These

shim adjustments

lower the drive end of the motor and raise the non-drive end enough

so

the centrelines of

the

motor hot

and

the centreline of the

gearbox

hot

are

common.

This section

helps

you

determine what the dials should

read when

the correct shim

adjustments

are completed. Line

4 represents

the cold

motor offset centreline. To

establish

the

S1

position for line

4,

subtract or

remove 0.003" shims

from the intersection

of

the

line 1 and S

r

plane.

To establish

the

52

position for line

4, add 0.00

I

"to the

intersection

of the

line 1

and

Sz

plane.

Where line

(4)

crosses A and B dial

planes,

these

values

indicate

that the correct

dial reading for

the cold offset

motor A dial reads'0.002"

TIR

and

dial B

reads

-0.00025".

The

previous

example

is

a

guideline

to show

you

how to align

a

motor to

a

gearbox

cold,

taking

into account

the thennal

growth

of both units and

the amount

of original

misalignment

present.

Once the

alignment is complete

it must be confirmed by

some

feedback loops.

First, the cold offset

rnisaligned machines

result in

dial

readings that are

not

zeros.

The readings expected

are

predicted

from line 4 where line

4

crosses the

A

and

B dial

plane

lines. Secondly, upon stafi-up the

unit vibration

should be

a little high until

the

motor and the

gearbox

reach operating temperatures.

At

this

point

very low

acceptable vibration

readings indicate

*'hether

the

procedure

is

successful.

lfthe

vibration

level

continues

to increase

to

higher levels after start-up, it is

safe

to conclude

that the

procedure u'as not

successful and the unit

must

be

realigned

and

rechecked

for

mechanical integrity.

Mechanical

integrity is a term that describes the

mechanical condition of

a

machine.

Good mechanical

integrity

means that the machine is

in

excellent

condition;

poor

integrity means

that

the machine has

a

number of mechanical faults.

Hot Alignment

Methods

Hot

alignment

is

a

tenn that describes

a

number

of ways of checking

the alignment

of

one

or more

shafts

in relationship

to each other

once the rnachines have

been

put

online

(started

and

loaded)

and

a

thennal equilibrium has

been

reached.

Thermal equilibrium

means

that

the machine

has reached

its ruming temperature throughout

and

no more

heating or cooling

will

take

place. In

other

words, the

unit has reached an operating

temperature

throughout

and there

will

be

no more metal

thermal

growth.

1 60403ap3.0.docx

O 2007. Her Majestl'the

Queen

in right of the Province of Albena



."

;

lf

The quick

hot alignmenr check is a very

poor

method

that

can

give

enoneous results. This

is

because the hot running unit is shut down,

isolated and

prepared

for

a conventional dial

or laser

procedure.

This

method is

poor

for the following

reasons.

e

Shutdowns

are

costly

and unpopular

with

operating

personnel.

.

The equipment cools down

very

quickly,

which

results in ever-changing

alignment readings.

r

The

media

that had been flowing through the machine

stops

flowing; as a

result,

hydraulic

effects

cease

and

moments

of force are eliminated.

.

Couplings sornetimes

have

to be disconnected, u'hich this takes up valuable

time.

o

Close

proximity

to high temperature

casings

can result in

burns to

personnel.

The

traditional

hot alignment method is not reliable and rarely works.

Online

Hot

Alignment

Checks

Online

hot

alignment

means

that

you

can

track the

alignment changes

of two or more

shafts

in relation to

each other by some

specific

procedures.

The

procedures

do

not

require the

unit

to be unloaded

or shut dorvn.

The

procedures require some

permanent

measuring devices to

be

mounted

on

the machines being

monitored.

The most common

methods

are

the

optical

tool method,

the laser beam and

target method,

water

stand

and

proximity

probes,

Dodd's bars

and transducers and

the Essinger tooling

ball method.

All

of these

methods

provide reliable online

alignment

data. The methods

vary

greatly in

cost,

complexity

and ease of

use.

None of the

rnethods are applicable to every situation.

Review the

rnerits

ofeach

system and choose the

system

that

best

fits the

need.

Precaution

With the exception of instrumented couplings, all of the

methods listed

belorv use cold

coupling alignment

readings

as

baseline

from

which

to

calculate

(or

plot)

hot

coupling

aiignment.

An instrumented coupling has alignment

probes

built

into

the coupling.

Regardless of the

method

used,

it is vital that the cold baseline

data be taken

at

the same

tirne

the

cold coupling alignment

data

is

taken-

For example,

reliable results cannot be obtained by taking coupling data

in

the cool of

the

morning

and

hot

alignment baseline data in the blazing afternoon

sunshine.

Take

the data

sirnultaneouslv.

I

604tljapi.0.docx

O 2007. Her Majest]'the

Queen

rn right

of

the

Province

of

Alberta



Optical Methods of Determining

Machine Movements

Optical methods

(Figure

7) use very

precise

surveying techniques

to determine

machine

movements,

from which shaft

alignment

information can

be obtained.

To use the

optical

method,

the coupling alignment is

performed

in

a

conventional manner.

Once the alignment

is satisfactory, the

vertical

and

horizontal

baseline

data are

obtained

with

the aid

of

precision

levels and transits.

'fhis

baseline data

is taken

off

flat-machined split

joint

surfaces.

When the equipment is

put

online

and brought

to equilibrium.

this same

optical

instrumentation is used to detennine the movement of each of the machines

with

respect to

the baseline data.

From this data.

runnins

alisnment can

be

plotted

or calculated.

.

Cold alignment

is

the benchmark.

.

Movement

is referenced

to line af sight.

.

Optical

levels and

jig

transits are

used

to determine

vefical and

horizontal

machine

movements.

Figure 7

-

Hot check by

optical

means.

Some companies

employ

in-house specialists

to

conduct hot alignment

checks by

optical

methods

and some

use one of the several

commercial firms

rvho

offer

these services.

Lasers

Several variations of

laser rnonitoring

(Figure

8) are available. Machines

are

ty'pically aligned

in

a

conventional

manner using dial indicators

or lasers;

another

laser/reflector system

is

used

to

rnonitor

the movement

of

one

machine casing

with

respect

to the adjacent casing.

.

Cold alignment

is

the benclrmark.

.

Laser system is

used

to

monitor

relat:ve

machine movemenls.

.

Data

is analyzed and

recorded

by computer system.

Figure

8

-

Hot check

by

laser

systems.

From

this data,

coupling alignment can be

determined

by

plotting

or

by

calculations.

In

some systems, the

laser equipment is mounted

perrnanently

upon the equipment.

In

other

systems, brackets are

used

to

permit

the lasers to

be

installed

and/or

removed

during

operation.

I 60.103ap3.0.docr

ic-

2007.

Her Majesq the

Queen

in right of the

Prorince of

Albena

It



Proximity

Probes

with

Water-Cooled

Sfands

With

this method

(Figure

9), water-cooled

stands are attached

to the

foundation

near

the

couplings

and outboard

bearing

housings.

These

stands are

support electronic proxirnity

probes,

which

monitor

the movement

of the coupling,

shafts

and/or

machine

casings

relative

to

the foundation.

.

Cold

alignment

is

the

benchmark.

.

Machine movements

are referenced

to water

cooled

stands.

.

Prcximiiy

probes

detect

machine

movements;

data is monitored

and/or

recorded.

Figure

9

-

Hot

check by water-cooled stands and

proximity probes.

With the above method, coupling alignment is done

as

per

norrnal

plant

standards,

at

which time baseline

proximity probe

readings

are taken. Equipment movements

are

monitored via these

probes

as

the

equipment

is

brought online and comes to equilibrium.

While the machines

are

changing alignment

due

to

increases

in

operating temperatures,

the readings

given

by the

probes

are monitored and recorded. Movenrent

of the

equipment

relatit,e

to the

proximity probes provides

data

from rvhich

to determine

running

aligrunent

of the equipment.

Dynalign

(Dodd)

Bars

This method

(Figure

l0)

of continuous. online

monitoring

uses

proximitl'

probes

fastened

to

pemanently

rnounted

brackets on the

coupled machines.

The brackets

are arranged

in

a

fashion

sirnilar to that ofindicator

brackets

used

in

the

reverse

alignntent ntethod,

except

that the brackets

are

mounted to

the

housings, not the shafts.

Vertical

and

horizontal

dara

from four

probes

supply

information

about the relative movement

of the machine

casings.

Figure

10

-

.

Cold

alignment rs

the benchmark.

.

Relaiive

machine movements are referenced

to bars

affixed

to opposite

machine.

.

Proximity probes

detecl

machine movements;

dala is monilored

and,lor

recorded.

Hot

check by Dynalign

(Dodd)

bars.

With

this method, cold

alignurent is done in

the

as

per plant

standards and baseline

data

is

read

off

the

probes.

Output from

the

probes

is

then monitored

and/or recorded. Data

is

sufficient

to

plot graphically,

calculate

mathematically,

or

indicate

where

the equiprnent

has

moved

during

thermal

growth

changes

C.W.

18

I burlUiapi.0.docx

e,2007.

Her

Majesb,the

Queen

in righr

ofthe Province

ofAlberra



Benchmark

Gauges

(Acculign

Sfeet Tooling

Ball

Method)

This

systern (Figure

I 1)

monitors the

movement

of bearing

housings

or machine

casings

with

respect

to

the equipment

foundation.

With this system, permanent

benchmarks

are

mounted

on the equipment

and the foundation.

Once

the

n.rachine

is aligned,

benchmark

gauges

are

used to detertnine

baseline

measurements

between

the

foundation-mounted

benchmarks

and those

mounted

on

the equipment.

when

the

machines

are

brought

online, benchmark gauge

readings

are

again taken to detennine

the relative

movement

of

the equipment.

.

Cold alignment

is

the

benchmark.

,

lVlachine movements

are referenced

to foundation.

.

Movernents are measured bv dioital

benchmark

gauge.

.

Alignment analyzed by PC

program.

Figure

11 -

Hot

check by benchmark

gauges.

Running

alignment of

the

coupling is

normally calculated

by a

personal

cornputer

(PC)

software

program,

but

can

also be detennined

by

graphical

methods.

Instrumented

Cou

plings

Instrumented

coupling

system

(Figure

12) electronic

probes

are

built into

the couplirrg

spacer.

Power

is supplied

to the

probes

by

a

stationary

transformer. The

signals from

the

probes

are

retrieved in

a

similar

manner.

This

arrangement

provides

online,

continuous

monitoring

of coupling alignment

as

well

as axial movement

of the coupled

shafts.

'

Base

data is

by coupling

caljbration.

,

Proxinrity

probes

within

the

coupling

detect misalignment.

.

Signals

and

power

are transmitted

by stationary transformer.

Figure

12

-Hot

check

by

instrumented

couplings.

dffirh

IJ:

W

1 60.103ap3 0.docx

io 1007.

Her Majesq the

Queen

in rrght

of the Provrnce

of Alberta

19



Satisfactory

and

long-lasting

alignment is

achieved

by

paying

attention

to details

throughout

the design, fabrication

and installation

of the

equipment. The

following

are

minimal

requirements:

o

rotating

equipment

that is

properly

designed

and

well-made,

a

well-designed

and

properly

executed

system

into which

the equipment

is

integrated

(this

rneans

choosing

the right

online monitoring

equipment

and

installing

it

according

to suggested

engineering

specifications),

knowledgeable,

careful and

experienced

craftsmen,

proper

training

of craftsrnen

and supervisory personnel,

appropriate tools,

standards

and/or specifications

detailing alignment

requirements

and

a

system to

assure

that

job

specifications

are

followed.

Characteristics

of

Online Monitoring

AIJ online

monitoring

methods require

a cold

accurate aligmnent to be

performed

initiaily

before

installing special online monitoring devices. The initial cold aligrunent

gives

the

necessary

reference

measurements needed betu,een

the machine shafts

and the

instruments.

Most online

methods are

very

susceptibie

to

unwanted accidental instrument

movement. For

example, the optical

system requires

the

precise

iocation

of

the telescope

on

a

tripod or base.

lf

the base is not

protected

by

a

house

with

windows the tripod may

be accidentally moved.

The result is

that all the readings are inaccurate and the

procedure

must start over

from

the initial cold alignment start

point.

Lasers are also vulnerable to

accidental external movements

of

stationary

pennanent

mounts. The

permanent

mounts

must

be of

rigid

design

with little

or

no

thermal

growth.

Water-cooled units made from

titanium

or

Invar

(high

nickel steel) are

the

preferred

types.

Proxirnity

probes

are fitted to special

constant temperature water-cooled

stands

that

are

secured

to the

same base. The danger or downside

ofthese

stands

is

that they are very

susceptible to accidental movement from

external forces,

such

as

personnel

contacting

them. Over tirne, vibration can

cause

mechanicai

looseness

because

of

cracks

in

the

stand.

Another

problern

that can cause all reference measurements

to be lost is

a

rvorker who

unknowingly removes the

stands

while

making a repair.

After

the repair is completed

the

stand

is

reattached

to the rnachine,

but all reference

rneasurements

are lost

because the

stand is mounted

in

a

slightly different location.

Dynalign

or

(Dodd)

bars are susceptible

to cracks

due to

vibration after

a

period

of time.

Once a crack develops,

all

the reference

lneasurements

are lost and

the online monitoring

gives

false information.

Benchmark

gauges

are also susceptible

to

accidental

external

forces

and

shifts

or cracks

in

the

foundation.

One

industry

standard used

to

check

multiple

machine

coupling alignment

is

the

machine

tooling ball

(benctmark

system), which is an online

mounting

system.

It

is

very reliable

and relatively easy to

use.

The next

section deals

with

this

system.

a

a

a

a

a

2&

I

60+0iapj.().docx

.e

2007. Her

Majesq the

Queen

in right

ofthe Province

ofAlberta



Online

Monitoring

of Coupling

Alignment

Benchrnark gauges

are

used to take

very accurate

measurements

between matching

sets

of benchmarks.

The

benchmarks are

stainless steel

8

-

18

metal

that has been

machined

to form

a ball

on one end rvith

some type

of

fastener

on the

other

end. These

benchmarks

are mounted

permanently

to the machine

and

the rnachine

base

so

that

measurements

can

be

taken between the balls at

any

tirne

desired.

Common

Styles

of

Benchmarks

Common

styles of benchmarks

are

discussed

in this

section.

Weld-On

Benchmarks

Figure

13 is

an

example

of a

rveld-on

benchmark. This benchmark is

on

a

fla non-

threaded

base

that is welded

directly

to the equiprnent and has the same 95o useful limits

as other benchmarks. The

base

is

'/a

inch in diameter. The measurement from

the

base

to

centreline of the ball is

3

inch.

Useful Limits in

Which

Figure l3

- A weld-on benchmark.

Threaded Benchmarks

Figure

14

is

a

simple

benchmark that is useful

for a wide

range

of non-critical

applications that do not require the

long-term protection

afforded

by

other benchmarks.

A

threaded

benchmark

is

a

one-piece construction

of 18

-

8 stainless steel and is

screwed

into

a

tapped hole and secured with a locknut. The stainless steel locknut is fumished

with the unit.

k

.:

(,,Q'l

l.

I

J/O

t

Usefui Limils

in Which

to

I

Use Benchnark Gauge ----J

3/B-16 NC

(remov*ble

locknut)

Figure

14

- Threaded benchmark.

I 60.103ap3.0.docr

@

2007.

Her

Majesr,v-

the

Queen

in right of the Province

of Alberta

zl



Covered

Benchmarks

Covered benchmarks

(Figure

1,5)

are recommended

for

general

turbo

machinery rvork

(turbine-related

equipment). These are

one-piece

construction oftype

l8

-

8 stainless

steel

and

are

furnished with

a

%"

x l6 NC

carbon

steel

stud

for mounting

directly into a

tapped

hole.

Altematively.

the

stud

can be removed

for mounting directly

on

a

'.{"

x

l6

NC male thread,

or the base

of

the benchmark

can be

welded

directly to

the equipment.

If

threaded fasteners

are used. it is

recornrnended

that the

assernbly

be

bonded

in

place rvith

epoxy

to

avoid inadvertent

movement. The

protective

cover

is nrade

of moulded plastic,

rvlrich

offers

good

mechanical ploperties

and excellent

corrosion

resistance.

To mount

this benchmark

in

concrete,

use

a

benchrnark

mount suclr

as

that shown

in

Figure

16.

Properly tnounted,

this

protected,

stainless

steel benchmark affords alignment

reference

for

the

life of the

equiprnent.

3iB

-

16 NC

Uselul

Limits

in

Which to

,/

-i

use Benchm6lla $6uqg

-----l

Figure 15

-

Covered

benchmark.

Benchmark

Mounts

Benchmark mounts

(Figure

16)

provide

an excellent rneans

of mounting

covered

benchrnarks to concrete or lnasonry structures

or

foundations. The

units include a

concrete

anchor,

'11"

-

16 NC

stud,

and a heavy rnounting

ll'asher.

This mount

is installed

in

a5l3

inch

diameterby

2tla

inch

deep

hole.

Epoxy

cement

rnay be

applied upon

assemblv

to

enhance

rnechanical intesritv. The benchmark

is

not

included.

318-16 NC

$tud

2118"

Figure

l6

-

Benchmark

mount.

--r--

-

3/8

I

i

t

l

I1/4"

"k

I

t\

l;-

[-

23,'o"

to

Rerrrove Cap

tt

I 60.+()iap-i.0.doc\

C 2007. Her Majesry

the

Queen

in righr of il:e Province of Albena



Masonry

Benchmarks

The masonry

benchmark

in

Figure

17

is made

with

a

o/ro

inch

diarneter

base

which can be

bonded

by epoxy directly into a'l3 inch

diameterby |

'la

deep hole.

This

is

especially

useful for non-critical

applications

requiring

placement

of

benchmarks in concrete.

It is

made of one-piece

construction of type l8

-

8 stainless steel and

has

the same 95o useful

limits

as

other benchrnarks. The dimension

from

the

base

to the centreline

of

the

ball

is

I

-/a

lnCh.

,-)n

Useful Limits in Which

to

,

?5'

use Benchmark Gauge

*--,/

|

Epoxy

.(9/16',:

Figure

17 -

Masonry benchmark.

Benchmark Protectors

Benchrnark

protectors (Figure

18)

are recommended

for use

u'hen the

benchmark must

be

placed

in

a

location in which

it

is

subject to mechanical damage. These

protectors

are

made

of

galvanized pipefittings

and

come complete

with four

concrete anchors and

screws

for mounting. Anchors

require holes '/z

inch diameterby

I'la

inch

deep.

The

benchmark is

accessible

by unscrewing the

cap and

pipe nipple. The floor flange need not

be

removed to take benchmark

gauge

readings.

Dimensions

are approximi

Mounts with fcur concrete

anchors

(furnished}.

d g

a.)

A1/'\

q/2

Figure l8 - Benchmark

protector.

I

60403ap3.0.docx

O 2007, Her Majes4

the

Queen

in

rjght of the Province

of

Alberta

,3



11'

NOTE

Once

benchmarks have been

mounted in

strategic locations

they

should

be

protected

from

external forces

that can move

the ball.

Mounting Benchmarks

Mount all benchmarks

as close as

possible

to the shimming

planes,

as

shown in

Figure

19.

Figure l9

- Showing

end views of the benchmarks and

gauges installed.

NOTE

Benchmark

gauges

are only used for

a short time to take accurate

readings

and then they are stored in their wooden

cases.

60'Mininr*m

12S"

fiirim*m

9C*

L.4inin:um

S*"

tu'linimunt

"120.

l,4inimum

?il'

I'n4inirrun't

.i,

I 60.103ap3.0.docx

O 2007. Her Majest)'the

Queen

rn right

ofthe

Province

ofAlberta



I

Basic Benchmark

Gauge

Set

(ltem

1M for Metric

Units)

Benchmark

gauges (Figure

20)

are specifically designed for

conducting

online checks for

turbine-related alignment.

The basic

benchmark

gauge

set

consists

of a telescoping

column with an electronic

dieital readout.

six extensions. a 25-inch

(625-mm)

standard

and an

inclinometer.

Indicator

Tooling

Ball

Spring Lcaded

Telescoping

Sleeve

Dial

lndicator

Mounted

in Bar Assembly

Standard

Inclinometer

to

Measure

Bar

Angle

Essinger Bar

Kit

Figure 20 - Essinger benchmark

gauges.

The

benchmark

gauge

is spring-loaded

with spherical

seats

at

either end to match

the

spherical benchmarks

that

are

mounted

on the equipment. The

gauge

is self-supporting

when placed

between

pairs

of benchmarks.

The range of the

benchmark

gauge,

u,ithout

extensions, is 25 inches

to 30 inches

(625

mm

to 750 mm).

The six extensions

give

the

tool a

range

of

25 inches to 60 inches

(625

mm to

1500 rnm) in increments of 0.001 inch

(0.01

mrn). The

standard

and the extensions

are

constructed

of lnvar. The low coefficient

of thermal

expansion of this material

greatly

reduces

measure[lent

errors

resulting from thermal

expansion

of

the

tool.

The

standard

and the extensions are

manufactured to

an

overall accuracy of 0.001

inch

(0.025

mm) in

length.

The exposed

portions

of

the

tool, including

spherical

seats,

are made of stainless steel.

,r,...

f,t

Essinger

Bar

$et

Up

.,Fd1

,

*try

"

"='tt'S

uy\

lnclinonreter

#

df

O 2007, Her Majes4'the

Queen

in flght

of the

Province

of Alberta

160403ap3 0.doc>;

:=

25



Working

Example

of

Benchmark Procedure

Align

the machine to

a

high

degree of accuracy.

The

machine must be locked out

(not

running or turning over) and must be of

ambient temperature.

Once the

machine is aligned,

fasten

the

benchmarks to the machine and

the

base.

as

close

as

possible

to all shimrning

planes.

It becomes

difficult

to mount the

balls

so the included

angle

between the

base

and the benchrnark

gauge

is 45o. Oil lines, instrument

gauges

and

other equipment

sometimes

get mounted

in

the benchrnark

tool

pathway,

which forces

you

to

choose

a slightly different angle

of approach. This nerv

angle

may

require

installing new tooling balls in the base

or on the machine

housing.

If

bearing

housings are

readily

accessible, benchmarks

are

located as in

Figure

2lA.

Where

they are

not readily accessible,

an alternate such

as

that shown

in Figure

21B

may

have to be used.

Figure

21 - Benchmark

procedures.

The

benchmarks

can be

attached

to the

machine by drilling and tapping

holes in the

machine bearing

housings. The

fasteners screrved

into

the

drilled

and tapped

holes should

be installed

with a

permanent

thread-locking

compound

so

they do not

vibrate

loose.

The

benchmarks rnounted

in

the

base

may

be

cemented

in.

bonded

in rvith

epoxv.

or

welded

or

threaded to

the

base

structural steel.

All of the benchmarks should

be

protected from

external

accidental contact,

which can

bend or

distort them and

change the benchmark

gauge reading.

Using

an electrical or rnechanical benchmark

gauge,

measure

the

distances betu,een

pairs

of benchmarks. The angles and

measurernent

readings

are

taken and recorded for each

position.

The benchmark

gauge

set includes an

inclinorneter,

which uses a

pendulum

to

fileasure the benchmark

gauge

angles

in

relationship

to

level

base.

NOTE

Remember that

an

acceptable

cold alignment

must

be

completed

first.

B.

.

to

1

60.103ap3.0

docx

@

2007. Her

Majesq'the

Queen

in right of

the

Province

of

Alberta



i;ri:

.,;:

:,

l1r1

Lt\

l

Self-Test

1.

Why

misalign

a

set

of

machines

at the coupling rvhen perforrning

an

alignment?

a) to

be

within

coupling specifications

b) to account for coupling

wear

c)

to offset

for

thermal

growth

d)

to correct for

seasonal

foundation

mover.nents

2.

Is

it

possible

for two

coupled rnachine shafts to share

a common centreline in

the

vertical

and

horizontal

nlanes?

a)

yes

b)

no

3.

If

a motor

and

pump

have

a vertical

mount

(shafts

up and

down, not horizontal) do

they require

precision

alignment,

like horizontal units?

a)

yes

b) no

1.

lncreases in ternperature

and pressure cause

a

rnachine shaft

to

change

its

position

slightly.

a) true

b)

false

5.

What is

a

moment

of

force

caused

by

a

flowing media?

a) A

force

generated

in

the same

direction as

the

flowing

media.

b) A force

on

the

housing

generated

in the same direction as the

media travel.

c)

A hydraulic

force caused by

pressure

pulsation.

d)

The windage force created at the coupling.

6.

ls it possible to

predict

accurate

A

and B

cross dial sweep

readings

once the rrachine

has

been offset

for

thermal srowth?

a)

yes

b)

no

7.

What

is

the

value

of the

information collected when

you perform

a hot aligmnent

check?

a) It

deterrnines machine

foundation integrity.

b) It

indicates

soft

foot

conditions.

c) It reveals improper

coupling

spacing.

d) lt

reveals relative

shaft

positions.

8.

When

shafts

are

not

aligned

u,ith

each

other in the vertical and horizontal

planes

when running.

what

is the most

corlmon

result or syrnptom?

a) Bearings develop

oil whirl.

b)

Bearings wear

until

they

align

themselves.

c)

Vibration levels

increase.

d) Alignment

nleasurements

change.

U

U

I 60:+03api.0.docx

@

2007. Her Majest]

the

Queen

rn right

of the

Province

olAlberta

U



a:a::,a.:aaa:::::.a.a:::,::.

tt :

:i'' I ::rl:i::::,:::ii:l ll::

9. Why must

you

acquire

a safe work

permit

after receiving an

alignment orientated

u'ork

order?

a) Management requires it.

b) OH&S

requires

a

copy.

c) You require it for

your

records.

d)

It

is

a

requirement

for

personnel

safety.

10. The

purpose

of a millwright racking

out

a

breaker

rvithin

the local M.C.C.

before

performing

an alignment is:

a) to

prevent

rnachine

shaft

rotational

drift.

b) to

prevent

machine

shaft

rotation.

c) to

prevent

accidental starts/runs.

d) to

prevent

breaker

contact arcing.

1

1. Why must all energy sources

connected

to

a

machine be blocked

off,

locked and

tagged before

alignments are

commenced?

a) to

prevent

uncontroiled

process media

from flowing

b)

to

prevent

unskilled

workers

from being trapped

inside

c)

to

prevent unusual sequence

ofalignment

events

d)

to

prevent

an

unwanted

high-speed

roilover, either

foru'ard or ret'erse

12. The

procedure

to

chain some

valves in the closed

position

is required before

perfonning

an alignment

(assume

the valves are

chained. locked

and

tagged).

Why?

a)

It

gives you peace

of

mind.

b)

lt

protects

fellow

u,orkers.

c) It

prevents

energy

flowing.

d) lt

is a

form oflockout

safety

required.

13. After locking out a breaker at the M.C.C.

and

placing

the information tag

on the

lockout device, what should

you

do at the machine before commencing with

a

coupling

alignment?

a)

Check that all tools are

available.

b) Remove

the coupling

guard.

c)

Rope

offthe area.

d)

Try the local cornmand station.

14.

To align

a

turbo compressor

you

must have

the stearr lines blocked and

bled off as

well as having the valves

chained, closed and locked.

Should dynamic

compressor

piping

also be isolated and

bled offand locked out?

a) No. it is not necessary.

b) Dynarnic units

isolate

autornatically.

c)

The compressor state does

not matter.

d)

Yes,

it

should

be done because

backflows energize

the unit.

15. When aligning

an electric

motor to

a

hydraulic

pump

the system including the

accumulators

should be

bled off

and then

isolated because:

a)

an increase in temperature could cause the

pressure

safety to open.

b) high-pressure trapped oil could backflou'through the

pump.

c)

other components in the system

rnight

be

energized.

d) no system

pressure

is required.

160403ap3 0.docx

O 2007, Her

Majest)

the

Queen

in right ofthe

Province

ofAlbena



16.

What

can happen

to millwrights

perforrning

shaft aiignment

on

a

pump

if

accidental

reverse

flow

ofoil

through

a

hydraulic

system

occurs?

a) Nothing

will happen

because

there is no

shaft

movement.

b)

The

pump

rnight

run forrvard

and injure

them.

c)

The

purnp

might motor

backwards

and injure

thern.

d)

The

dial

brackets

and

alignment

tools

attached

to the

shafts can

catch on

clothing

and injure

the

worker

if the pump

motors

backwards.

1 7.

Lasers

can cause

serious

eye injury due

to:

a)

direct viewing.

b)

indirect

viewing.

c)

amplification

through

targets.

d)

flashes

caused by dust

parlicles.

18.

What is meant by

bucking in alaser unit mounted

on

a

rnachine?

a) It

is

a

laser self-check for

accuracy.

b) It is mounting the laser

bearn

centrally within

the

base.

c)

It

is

a

method

used to check the machine

housing for accuracy.

d)

It

is setting the

laser

to

a

benchmark location.

19.

Do

laser

beam targets hat,e a

set

of direct mechanical

microrneters?

a) No, they

are

not necessary.

b)

Yes,

they

alu'ays require

checking by constant feedback.

c)

Yes,

because laser beams can fail.

d) Yes,

because lasers

are not self-centring.

20.

Do laser

beams sag due

to

gravity?

a)

yes

b)

no

21.

Drive shaft

coupling

alignment

can

be used to check:

a)

drive

shatls

for

straightness.

b) u'ear in the

couplings.

c)

alignment of the motor

shaft to the

gearbox

shaft.

d)

degree ofshaft levelness.

22. Drive

shaft

(or

spindle

shaft)

alignment

uses

two dials

mounted:

a)

one

inboard

and one

outboard.

b)

one on the

rim

inboard.

the

other

on the face

inboard.

c)

both on the rims,

one inboard

and

one outboard.

d) both

on the

same

plane,

one inboard,

one outboard,

both on the

face.

23. When

using the formulae

to

calculate the required

shim moves

for a spindle

shaft, a

positive

value means that

shims should be:

a)

removed.

b) added.

24. What is

the

purpose

of

online coupiing monitors?

a)

to align shafts

when cold

b) to

align shafts when

hot

c)

to

provide

a

quick

hot alignment

check

d) to check

alignment

while

the machines

are

running

U

U

48

@

2007,

Her Majesq'

the

Queen

rn nght

ofthe Province

ofAlberta

v

I

60403ap3.0.docx



Self-Test Answers

1.

c) to offset for

thermal

gron'th

2.

a)

yes

3. a)

yes

4.

a) true

5. b)

A

force

on the housing

generated

in

the same direction

as

the media

travel.

6. a)

yes

7. d) It reveals relative shaft

positions.

8. c) Vibration levels

increase.

9. d) It

is

a

requirement

for

personnel

safety.

10.

c)

to

prevent

accidental starts/runs.

I

1. d) to

prevent

an

unr.l,'anted

high-speed rollover, either

foru'ard

or

reverse

12. d) lt is

a

form

ofiockout

safety required.

13.

d)

Try

the

local

command station.

14.

d)

Yes,

it

should be

done because

backflows

energize

the

unit.

I 5.

b)

high-pressure trapped

oil

could backflow

through the

pump.

16. d) The dial brackets and alignment tools

attached to the

shifts can catch

on clothing and injure the worker if the

pump

motors backwards.

fi. a) direct viewing.

18. b) It is mounting the

laser beam

centrally

u,ithin

the

base.

19.

b)

Yes, they always require checking by constant

feedback

20.

b)

no

21

. c) alignment of the

motor

shaft to the

gearbox

shaft.

22.

d)

both on the

same

plane,

one inboard,

one

outboard, both

on

the

face.

23. b) add

24.

d) to check

alignment while

the machines

are

running

1 60403ap3.0.docx

49

advanced alignment alberta module

Documents