ID Fan Manual

INSTALLATION, COMMISSIONING, OPERATION & MAINTENANCE MANUAL

AIROCHEM

INDUSTRIAL FANS

E ngineered products – m oving air efficiently since 1975

CLIENT: Themax Ltd (Enviro Division).

PROJECT:

ORDER NO:

AIROCHEM ENGINEERING COMPANY Plot No. B – 57, MIDC, Shiroli, Kolhapur, 416 122, Maharashatra, (INDIA) E-mail

- [email protected]

Telephone

- 91-230 – 2468107, 2468306

Fax No.

- 91-231 – 2658312 & 91-230-2460734

Web site

- www.airochemeng.com


INDEX

CHAPTER PARTICULARS

PAGE NOS

NO I

NAME-PLATE DETAILS

3

II

OPERATING SPECIFICATIONS

4

III

GENERAL

5

RECEIVING, HANDLING & STORAGE OF

6

IV V VI

EQUIPMENTS INSTALLATION INSTRUCTIONS PRE-COMMISSIONING & COMMISSIONING INSTRUCTIONS

8 11

VII

BEARING LUBRICATION

15

VIII

BEARING CLEARANCES

17

MAINTENANCE INSTRUCTIONS

18

LIST OF SPARE PARTS FOR TWO YEARS

20

IX X

OPERATIONS

XI

MOTOR STARTER RELAY SELECTION TABLE

21

XII

SELECTION OF ELECTRICAL CABLES

23

XIII

TROUBLE SHOOTING GUIDE FOR FANS

24

AIROCHEM ENGINEERING COMPANY

2


Chapter I - Name Plate Details of Fans AIROCHEM Industrial Fans -

Sr.No

Identification

1.

Type

2.

Size / Model

3.

Capacity ( cum/Sec.)

4.

Static Pressure @ optg.

ID Fan Centrifugal

Temp.(mmWG) 5.

Speed (RPM)

6.

Drive

7.

Motor Details

8.

Starter Details

9.

Serial No.

10.

Year of Manufacture


3


Chapter II - Operating Specifications of Fans Sr.

Identification

ID Fan

No 1.

Sr.No.

2.

Fan Type

3.

Model

4.

Gas Handled

5.

OperatingTemp. (oC)

6.

Capacity (cum/ Sec.)

7.

Gas Density (kg/m3)

8.

SP at operating

Centrifugal

Temp (mmWG) 9.

TP at operating Temp. (mmWG)

10.

Impeller

Diameter

(mm)

GD2(kg-m2) 11.

Impeller Speed (RPM)

12.

Drive Type

13.

Power consumed at optg. Temp. in KW

14.

Fan Efficiency (Static) at shaft in %

15.

Electric Motor Details

16.

G.A. Drawing No.


4


Chapter III – General The fan manufacturer, the driver manufacturer or the contractor building the installation can carry out the installation of fans. Large fans are usually installed as early as possible while access to the site is at its best. Small fans can usually be fitted in at any time.

The certified fan drawings must be available to allow foundations or structural steelwork to be designed and manufactured before the fan is delivered.

The space allocated for a fan must be sufficient to permit installation, care, disassembly and maintenance. Transport routes and lifting facilities must be available. Sufficient space must be allocated around the installed fan for the access of personnel. Operation may need to make frequent running adjustments. Maintenance personnel will require space to remove components and assemblies. Some fan designs require space at the non drive end. The motor may need space for the withdrawal of the rotor.

The ventilation of the fan site is very important. The electric motor must receive the necessary cooling. If the hazardous gases, harmful to the environment or highly flammable, are to be extracted, special ventilation requirements must be observed. It should be noted that the heat generated by the fans electric motor can be considerable. The electrical and control systems for the fan must also be protected against damage.

Mounting the fan unit on isolation mounting can create ducting and bearing problems. Ducting close to the fan can fracture if it vibrates. Using flexible connections adjacent to the fan can solve this problem. Short bearing life can be a problem if the fan does move appreciably on its isolation mountings. It is better to use an isolated foundation block.

It’s the user’s responsibility to ensure the fan unit is stored in suitable conditions and that the factory preservation instructions have been followed. Before placing the fan on foundation, thoroughly clean the top of the foundation, remove any thin ridges and roughen the top to provide good key for the grout. Prepare enough shims to level the baseplate, two sets for each foundation bolt. The shims should be longer than the width of bottom flange.


5


Chapter IV - Receiving, Handling & Storage of Equipments 4.1) Receiving

Most fans have been correctly, checked and inspected prior to delivery. They have also been subjected to a run test before leaving factory. When you receive the equipment, examine it carefully for damage caused in transit. If anything is wrong, both the manufacturer and carriers should be contacted within three days of receipt. Check that all items indicated in accompanying challans and /or packing slips have been received and if not contact the manufacturer immediately. If the fans are to be received by non-engineering personnel, it is recommended that skilled person carry out inspection on receipt.

If Fan assembly is received in CKD condition, ensure that all fan components are generally received as per list below, and as per challan/ packing slip in particular.

1) Casing in two or three parts, each having flanged opening with joining screws and nuts with spring washers. 2) Impeller with front locking washer, in case of overhung design & no washer, in case of simply supported design. 3) Inlet Cone. 4) Inlet Box. 5) Inlet VIV or Multivane Damper 6) Inlet and outlet flexible connections 7) Fan shaft with keys, bearings, adapter sleeves, locating rings and Plummer blacks assembled or bare shaft with keys and other items packed suitably. 8) Motor Pulley with locking washer. 9) Shaft Pulley with lacking washer 10) Foundation Bolts. 11) Shaft and /or motor assembly mounting pedestal, for overhung design.12) Plummer Block mounting pedestal, for simply supported design. 13) Motor mounting base. 14) Vee- belt guard/ or Coupling guard

4.2) Handling

The equipment should be handled carefully to prevent damage. Always use lifting points provided. Extra care should be given to Impeller or dynamic balance may be affected. The Shaft and Bearings are also important for on them depends the vibration-free running. Where the fan has been despatched as complete unit, never ‘sling’ under the shaft.


6


4.3) Storage

When fans are to be stored or installed for any length of time before running, special care should be taken as follows:

a) Where not specifically designed for outdoor use, they should be protected against elements, special care being given to bearings, motors, and rotating parts. b) Slowly run rotating parts at regular intervals to re-distribute the bearing lubricant, making sure that the shaft finishes at 180 deg. to its former position. Never leave the Fans stationary for any length of time adjacent to other vibrating machinery. These precautions will diminish the possibility of brinelling of the bearing and /or serious damage shaft damage. c) It is recommended that fans stored for any length of time should be Inspected again by the manufacturers representative before installation and start-up.


7


Chapter V - Installation Instructions 5.1) Concrete Foundations

Check the height and ensure that there is required grouting allowance between the foundation and the fan base. Suitable pockets should provided for the bolts to be grouted in after levelling and aligning. For vee belt drives, the foundation bolts should be of adequate length and well embedded in the concrete. The location of plinth should be checked in relation to the fan layout drawing. Use steel shims to obtain the correct height; the shims should be of the same width as base plate and placed each side of and close to foundation bolts. Pour the grout and ensure that the top of the foundation is covered evenly. If full depth cross members are fitted, ensure complete support. Remove the shuttering after five days, but allow the grout to harden for at least ten days. Do not allow the grout to dry not too quickly, and protect it from direct sunlight. In hot environments it may be necessary to cover the grout with damp sacks. Check the coupling alignment and adjust the shimming under the motor feet if necessary. Record all alignment settings. The suction and discharge ducting should be connected after the grout has hardened and final alignment has been completed. The ductwork must line up naturally with the fan connections. Do not force ductwork into alignment. Remove the ducting connections adjacent to the fan and clean out the ductwork, as best as possible. Recheck the coupling alignment with recorded figures and modify the ductwork if required. 5.2) Vibration Isolators

Use of vibration isolators, if recommended, use Dunlop or Polybond make isolators only, of appropriate capacity by consulting the manufacturer of vibration isolators or as supplied along with this fan.

5.3) Flexible Connections

If any inlet and / or outlet ducting is to be connected to fan, the same should be connected through flexible connections. Material of flexible connection should suit the temperature and


8


other properties of gases handled. Expansion joints should be provided wherever hot gases are being handled e.g. Flue Gases.

5.4) Fan assembly with common base for Fan & Motor

Lift the assembly & rest it on the foundation block. Align this assembly for exact matching of Suction & Discharge Centre Line. Insert correct size foundation bolts in the foundation pockets and through holes in common base.

Level the base frame with spirit level or water level by keeping in mind horizontalness of discharge flange & verticality of suction flange.

Now pour cement slurry into each foundation pocket around bolt. Allow for setting time of cement before fan is commissioned.

5.5) Fan assembly with common base for Fan only & separately for Motor

If fan is supplied with separate motor base frame, follow above procedure for foundation, with due care being taken for alignment of motor pulley and shaft pulley grooves, in one plane.

5.6) Fan supplied in knocked down condition ( CKD)

If fan is supplied in CKD condition, housing may have been supplied in split condition, separate shaft assembly, bearing mounting pedestal and separate motor foundation frame etc. In such a case, foundations will be cast as three separate foundation blocks or composite block as per drawing,. But all the three components will have to be separately grouted in following sequence.

5.6.1) Check top levels of all foundation blocks as per drawing. 5.6.2) Keep Lower Half of the casing on the foundation block. Align the same with respect to its Centre Line. 5.6.3) Keep Bearing Pedestals/Shaft Assembly in place on the foundation.


9


5.6.4) Fix shaft assembly onto these pedestals and check center line & level of the shaft by keeping spirit level on the machined surface. 5.6.5) Check all clearances / distances as per drawing. 5.6.6) Insert correct size foundation bolt in place for Casing & Bearing pedestals. 5.6.7) Half grout all foundation bolts with cement slurry and allow for twenty four hours to set. 5.6.8) Assemble fan impeller on the shaft at one end & driven pulley at the other end with key & locking washers in place, inlet cone and casing top part. 5.6.9) Spin Impeller to see if the rotation is free and does not bind or rub. 5.6.10) Inspect Impeller to see if it is the proper handing of the fan design. 5.6.11) Due care will be taken to maintain distance (both straight & angular between various center lines accurately) 5.6.12) Now carry out final grouting of all foundation bolts. 5.6.13) Assemble Inlet Box & Inlet / Outlet dampers, inlet outlet expansion joints, expansion joints, inlet outlet flexible connections. 5.6.14) Grout the motor foundation frame in place with driving motor & pulley or half coupling in place. 5.6.15) Align Driving and driven pulleys or Fan shaft & Motor shaft in case of coupled drive.


10


Chapter VI - Pre-commissioning & Commissioning Instructions IMPORTANT

6.1) Ensure that you have following important tools/ equipments / instruments with you for pre-commissioning.

Metallic Shims

Set of Spanners

Torque Wrench

Measuring Tape

Steel rule

Belt Tension Meter

Tachometer

Ammeter

Voltmeter

Megger

Dial Gauge

Set of Filler Gauges

Spirit Level

Plumb Line

Hook Spanner

6.2) Start-Up Check List.

Before putting any fan in operation the following operations should be completed.

6.2.1) Check and tighten all foundation bolts. 6.2.2) Check all set screws and tighten if necessary. 6.2.3) Check v-belt drive or coupling for alignment. 6.2.4) Use recommended belt tension. 6.2.5) Check the v-belt drive for proper pulley selection and make sure that they are not reversed. 6.2.6) Check & confirm that DE shaft bearing is made non-locating. 6.2.7) Make certain that no foreign loose material in ductwork to and from fanor in the fan itself. 6.2.8) Properly secure all safety guards. 6.2.9) Close any inlet and outlet dampers. 6.2.10) Ensure correct direction of rotation of motor shaft. 6.2.11) In case VIV damper is provided at suction end of fan, confirm that while opening of damper, air enters suction of fan is with pre-rotation in direction of rotation of impeller. If this does not happen, get the opening direction of damper changed suitably. This is very important, which otherwise will result in disturbance in fan performance.


11


6.2.12) Check whether the ball bearing are adequately greased as per greasing standards and locknuts of taper sleeves are tightened and locked properly after checking for required clearance between Balls / Rollers & Inner / Outer race of each bearing. 6.2.13) In case of vee belt driven fan, NEVER FORCE BELTS OVER PULLEYS OR ROLL THEM OVER PULLEYS WHILE SHAFT IN ROTATION.

6.2.14) Check electrical wiring for using adequate capacity cable and starter.

As

precautionary measure, check following in the presence of authorized person from electrical department. 6.2.14) Motor name plate details like HP rating, Speed, Full Load Current of Motor to Concur with recommended specifications. 6.2.15) Confirm that cable size and type is adequate for full load current of motor. Kindly refer to cable manufacturers catalogue. Improper size or excessive length of cable will result in excessive voltage drop at the motor terminals. 6.2.16) Check type of starter, relay current setting and confirm its suitability. 6.2.17) Carry out Megger test for electric motor between windings and body. Minimum resistance should be around 15 to 20 megaohm.

6.3) In case of Double Inlet Double width (DIDW) type fans, confirm that impeller is correctly mounted on shaft, which will result in Impeller running with fan blades backward inclined or as marked on Impeller.

6.4) Very Important Points Before Start-up for v-belt driven fans.

6.4.1) Check all pulleys groove surfaces for smoothness. Any sharp edges or burrs should be filed off, so that outer jacket of vee belt is not damaged. 6.4.2) Correct belt tension as per following table


12


Tensioning Forces for Wedge Belts

Belt

Small Pulley

Section

Diameter

Force required to deflect belt 16mm per meter of span Newton (N)

Kilogram force (kgf)

(mm) SPB

SPC

160 to224

35 to 50

3.6 to 5.1

236 to 315

50 to 65

5.1 to 6.6

224 to 355

60 to 90

6.1 to 9.2

375 to 560

90-120

9.2 to 12.2

6.4.3) Check alignment of both pulleys correctly which otherwise will result in rupturing of outside jacket of vee belts and hence failure of belts very fast. 6.4.3) Under no circumstances ID fan Damper should be opened completely till full temperature is reached & motor current is below name plate figure. 6.4.5) Important Note – Following precautions will be taken without fail to get maximum life of v-belts & for smooth operation of fan.

6.4.5.1) Check correct installation and take-up allowance for motor sliding Slots as per the following table.

Installation and Take-up allowances in mm length

Belt Pitch length

Installation Allowance

Take up

in mm

allowance in mm

SPB

SPC

in mm 1510 to 1830

50

1840 to 2170

60

2180 to 3500

75

2840 to 3500 3520 to 4160 4170 to 5140


30

100 50

125 160

13


6.4.5.2)

After tightening of V-belts, measure belt tension with the help of tension meter as above.

6.4.5.3)

Never run V-belt driven fan without applying correct V-belt tension.

6.5)

Switch on electrical supply and allow the fan to reach full speed.

6.6)

Progressively open damper, making sure that the system continues to function satisfactorily and motor does not overload.

6.7)

Check carefully for -

Correct impeller rotation

-

Excessive vibration

-

Unusual noise

-

If any problem is indicated, switch off the fan. Cut out electrical supply, check carefully the cause of the trouble, and correct as necessary

6.8)

Even if the fan appears to be operating satisfactorily, shut down after brief period and recheck items from (6.2.1) to (6.2.8) as initial start- up may have relieved tightness of belts and set screws, again ensuring that electric supply is cut out before attemting other checks.

6.9)

The fan may now put into operation, but during the first eight hours of running it should be periodically observed and checked for excessive vibration and noise. At the same time checks should be made on motor input current and motor temperatures to ensure that they do not exceed manufacturer’s recommendations.

After eight hours of satisfactory operation, the fan should be shut down and the power cut to check the following items and adjust if necessary. a) All set screws and foundation bolts including guard fixings. b) Drive coupling alignment. c) Vee-Belt drive alignment. d) Vee- Belt drive tensions should be readjusted to recommended tension. e) Security of flexible connections.


14


Chapter VII - Bearing Lubrication 7.1) Grease Lubrication

Fill the space between the balls or rollers with a grease which is suitable for the operating conditions. The free space around the bearing should normally be between a third and halffilled with grease. If the bearing is to operate at very high speeds, the quantity of grease in the free space should be just less than one third. Or, where the bearing is to operate at very slow speeds, the free space may be completely filled with grease.

An excess supply of grease is not recommended for ball or roller bearings. Heat is generated more often by too much of lubricants than too little. Heating takes place when rotating parts move through a large amount of lubricant, especially at high speeds..

7.2) Relubrication:

The service life of lubricating greases is limited. Mechanical stresses and ageing gradually reduces the lubricity. Ageing concerns mainly on oxidation process accelerated by high temperatures or the separating of the grease into the base oil & thickener. Morever, during use, grease becomes impregnated with particles from the rolling & sliding surfaces. It is therefore necessary in most bearing arrangement to replenish or renew the grease filling periodically.

The relubrication interval depends on stressing of the grease by friction, speed & environmental conditions. The relubrication period can be decided by referring to actual conditions and Bearing Hand Book.

7.3) Amount of relubrication grease

At the moment of relubrication, the bearing generally still contains a certain amount of grease. In order to avoid excessive greasing with closed housing space, the relubrication amount must be limited and decrease further if the relubrication intervals are shorter. In absence of any recommendations, the quantity of grease to be used can be


15


Calculated from following equation,

G = 0.005 DB gms. Where, G = Grease quantity, gramms. D = Bearing outside Diameter, in mm. B = Bearing width in mm.

7.4) Initial Grease Filling Required Per Bearing

Plummer Block No.

Grease Qty. in Grams.

SNA-510

100

SNA-511

130

SNA-512

160

SNA-513

200

SNA-516

250

SNA-517

300

SNA-518

320

SNA-520

350

SNA-522

400

SNA-524

500

SNA-526

600

SNA-528

700

SNA-530

850


16


Chapter- VIII – Bearings Clearances The following table gives Bearing Internal Clearance values before and after mounting. 8.1) Internal Radial Clearances of Spherical Roller Bearings with Taper Bore. Nominal

Clearance under zero measured Clearance under load in microns

Bore Size, D load in microns mm

Foe initial

Foe initial C3 Foe initial

Foe initial C3

Normal clearance

clearance

Normal clearance

clearance

Bearings

Bearings

Bearings

Bearings

30-40

35-40

50-65

15

25

40-50

45-60

60-80

20

30

50-65

55-75

75-95

25

35

65-80

70-95

95-120

25

40

80-100

80-100

110-140

35

50

100-120

100-135

135-170

50

65

120-140

120-160

160-200

55

80

140-160

130-180

180-230

55

90

160-180

140-200

200-260

60

100

8.3) Internal Radial Clearances of Double Row Self Aligned Bearings with Taper Bore. Nominal

Clearance under zero measured Clearance under load in microns

Bore Size, D load in microns mm

Foe initial Normal Foe initial C3 Foe initial Normal Foe initial C3 clearance Bearings clearance

Clearance Bearings

Bearings

clearance Bearings

24-30

15-23

23-33

0

20

30-40

19-29

29-40

0

25

40-50

22-33

33-45

0

30

50-65

27-41

41-56

0

35

65-80

33-50

50-69

0

40

80-100

42-62

62-84

0

50

100-120

50-75

75-100

0

65


17


Chapter IX - Maintenance Instructions 9.1) AIROCHEM make fan supplied to you is a professionally manufactured piece of machine and as such will need least maintenance. However, frequency of checking various components will depend upon conditions like, Nature of gas handled, Temperature of gases, Speed of rotation & Atmospheric conditions, where the fan is located. Generalization of fsn maintenance is waste of time. Fans operate in widely differing circumstances with vast array of materials. The best policy is to initiate a strict, very regular, routine inspection of equipments and continue this till a pattern of equipment behavior is apparent. At this stage it may be possible to relax the inspection routine in some areas. In absence of any specific instructions, the following are suggested. 9.2) Routine Maintenance Chart

When taking over plant at beginning of the shift, operator

EVERY SHIFT

should check that all bearings are cool. Check for undue vibration. If present, stop fan at earliest

EVERY WEEK

opportunity and remove the cause. EVERY 3 MONTHS

Check grease lubricated bearings for saponificatoin.

EVERY 6 MONTHS

1) Consult motor manufacturers manual and carry out instructions. 2) Examine v-belt pulleys for any chipping, tension of v-belts, OR, 3) Check coupling alignment and condition.

EVERY MONTHS

12 1) Examine impeller, fan bearings, and inlet cones. Check vbelts, pulleys, or coupling elements. If any wear, replace as necessary. 2) Check clearance at impeller, level at shaft, and general alignment. Adjust as necessary. 3) Check all foundation bolts for tightness. 4) Refer to Motor and control gear manufacturer’s maintenance instructions and act accordingly. Grease lubricated bearings should be cleaned out and grease renewed.


18


9.3) Special Maintenance care for ID Fans

Induced Draft fans of bagasse-fired boilers are normally preceeded by installation of fly ash removal equipment such as Dry Multiclone Dust Collector, Wet Scrubber or Electrostatic Precipitator.

These equipments bring down suspended particulate matter in flue gas below specified limits & thus save impeller of ID fan from abrasion.

However some times due to malfunctioning of such equipments, ID fan impeller does get eroded fast & this phenomenon has to be watched carefully.

In case Wet Scrubbers installed before ID fan, due care has to be taken to ensure that outlet flue gas temp. from Wet Scrubber does not fall below 900C to avoid water vapour condensation. This will result in fast corrosion of not only impeller but casing also.


19


Chapter X )

List of spares for Two years Operation (Except Electricals)

Sr.No

Description

01

Impeller Assembly

02

Shaft

with

Drg. No

Make

Material

Size

Quantity 1 No.

keys

and

1 Set

locking bolts. 03

Shaft Bearings

2 Nos.

04

Bearing Housing

1 No.

05

Taper Sleeves with lock

2 Sets.

nut. 06

Locating Rings.

1 Set.

07

Motor Bearings (DE)

1 No.

08

Motor Bearings (NDE)

1 No.

09

Motor Cooling Fan

1 No.

10

Shaft Seal Assembly

1 Set.

11

Bearing Seal Assembly.

1 Set

12

Impeller Lock Nut

1 No.

13

Impeller Fixing Key

1 No.

14

Driving

fixing

1 No.

15

Driven pulley fixing key.

1 No.

16

Vee belts

1 Set.

17

Impeller Locking Washer

1 Set

pulley

key.

with bolts. 18

Driving Pulley Locking

1 Set.

Washer with bolts. 19

Driven Pulley, Locking

1 Set.

washer with bolts


20


Chapter XI ) Squirrel Cage Induction Motor Starter Relay Selection Table Sr.

Motor H.P.

No.

Full load

Relay Scale

Relay Scale

Back-up HRC Fuse

Current

for DOL

for Star Delta Rating for

Amps

starter

starter

in Amps

in Amps

DOL

Delta

Starter

Starter

In Amps In Amps.

01

0.5

1.05

1 – 1.6

-

6

-

02

0.75

1.5

1.5 – 2.5

-

6

-

03

1

1.8

1.5 – 2.5

-

6

-

04

1.5

2.5

2.5 – 4

-

10

-

05

2

3.40

2.5 – 4

-

10

-

06

3

4.60

2.5 – 6.5

-

16

-

07

5

7.30

6.0 – 10

-

20

-

08

7.5

10.5

9.0 – 14.0

-

25

-

09

10

14

10 – 16

-

25

-

10

15

20.60

18 – 24

10 – 16

50

35

11

20

28

20 - 32

13 – 21

63

63

12

30

40

28 – 42

20 – 32

100

63

13

40

52

45 – 70

28 – 42

160

100

14

50

64

60 – 100

28 – 42

160

100

15

60

76

-

45 – 70

-

120

16

75

96

-

45 – 70

-

160

17

100

140

-

60 – 100

-

200

18

125

156

-

90 – 150

-

250

19

150

190

-

90 – 150

-

250

20

170

215

-

120 – 200

-

320

21

220

278

-

120 – 200

-

350

22

245

310

-

120 - 200

-

350


21


23

270

345

-

180 – 300

-

400

24

340

430

-

180 – 300

-

400

Note: - a) Above motor rating in HP are at 415 V, 3PH, 50 HZ supply. b) Actual ratings value & current may change from manufacturer to manufacturer.


22


Chapter XII ) Selection of Electrical Cable Current Ratings (AC) in Amps. for 650 / 1100 volts Armoured or Unarmoured 3 or 3.5 core Copper / Aluminum cable.

Nominal Cross

Current Rating in Amps.

Section Area sq. mm.

Laid in ground at 300C

Copper

Aluminum

In Air at 400C

Copper

Aluminum

1.5

21

16

17

13

2.5

27

21

24

18

4.0

36

28

30

23

6.0

45

35

39

30

10.0

60

46

52

40

16.0

77

60

66

51

25.0

99

76

90

70

35.0

120

92

110

86

50.0

145

110

135

105

70.0

175

135

165

130

95.0

210

165

200

155

120.0

240

185

230

180

150.0

270

210

265

205

185.0

300

235

305

240

240.0

345

275

355

280

300.0

385

305

400

315

400.0

425

335

455

375


23


Chapter XIII -Trouble shooting for Fans Symptom

Possible cause

Remedial Action

Fan won’t start

Low voltage at motor terminals

Check cable size and length

Power failure

Check all power supplies

Blown fuses

Check all fuses

Motor single phasing

Check motor and wiring

Control switch contacts open

Check all instrument switches in motor contactoer circuit

Low flow

Inlet and/or outlet damper closed

Check dampers position and correct.

Excessive system resistance

Check calculations, gas temp, etc.

Fan speed very low

Check drive, frequency, and

Impeller partially blocked

voltage.

Wrong direction of rotation

Clean impeller and rebalance. Reverse 2 phases in 3-phase

Wrong direction of VIV damper rotation

motor. Remove viv damper and correct.

High flow

System resistance lower than specs.

Check

calculations,

throttle

damper, and reduce fan speed. Fan speed high.

Check motor frequency, pulley ratio.

High power

High flow

Check as above.

consumption

Electrical faults

Voltage

frequency

incorrect,

check supply. Motor problem, check motor High bearing

Wrong selection of grease quality.

Check and correct.

Temperature

Over- greasing or under- greasing.

Fill with proper quantity of grease.

Looseness of sleeve

Tighten sleeve.

Improper clearance between outer race Check clearance with filler and rollers.


gauge and correct.

24


Outer race rotating in housing.

Tighten cap properly or change plummer block.

Fan vibration

Poor alignment

Check for alignment and any bearing related problems. Check coupling or v-belt drive assembly. Check base plate grouting. Check ducting.

Damaged Impeller

Check vibration harmonics, clean and/ or repair impeller, rebalance

Motor Vibration Poor alignment

Check alignment and coupling/ vee drive assembly. Check base plate grouting. Check bearing clearances

Bearing Problems

Check vibration signature for bearing faults. Check motor for loose rotor bars.


25

ID Fan Manual

Recommend Documents