FläktGroup EULC Axial flow fan Installation guide

Brand: FläktGroup

Model: EULC Axial flow fan

Type: Installation guide

FläktGroup EULC Axial flow fan provides efficient air handling solutions with its adjustable blade pitch, enabling precise airflow control. Ideal for various applications, including ventilation, air conditioning, and industrial processes, this fan excels in energy efficiency, reliability, and quiet operation.

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 1 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

General

The fan is available in two different versions as shown in

Figures 2 and 3.

Arrangement 1: Open suction. The impeller is mounted

directly on the end of the motor shaft.

Arrangement 7: Open suction. The impeller is mounted

on the intermediate shaft, connected to the motor shaft

by means of a flexible coupling.

The fans can be supplied in two different versions, which

differ in terms of the blade pitch control system.

EULC, d = 1: Pneumatic, single-acting actuator incorpo-

rated into the impeller. An increase in the pressure signal

to the actuator increases the blade angle and thus increases

the delivery air flow. The blade angle is controlled by an

externally mounted positioner.

EULC, d = 2: Mechanically controlled fan which can be

equipped with an external, double-acting electro-mecha-

nical actuator. The control mechanism of the impeller is

actuated by a linkage.

Commissioning the fan

1. Lubricate the motor and shaft bearings before starting

the fan. Lubricate the shaft bearings through the grease

nipples on the fan stand. The quality and grade of gre-

ase are specified on a plate at each lubrication point.

On Arrangement 1 fans, the grease nipples, if any, for

the motor are connected to external grease nipples.

2. Avoid starting the fan against a closed damper or at a

high blade pitch setting.

3. On parallel operation of several fans under control of a

common main controller, check that the loading is

equally distributed, e.g. by comparing the motor cur-

rents. Carry out adjustment by means of the zeroing

screw and the stroke factor screw of the positioner.

Maintenance

CAUTION: To avoid injuries to personnel and damage

to the machinery, remove the fan fuses and open its safety

isolating switch before doing any work on the fan.

General

For maintenance on the motor, follow the motor suppli-

er's instructions. If the shaft coupling of an Arrangement

7 fan must be aligned for any reason, make sure that the

radial or axial run-out does not exceed 0.5 mm. For other

particulars, follow Fläkt Woods instructions 142-1A for

shaft couplings (available from your nearest Fläkt Woods

representative).

If any of the joints listed below has been broken, retighten

to the tightening torque specified in Table 1 or 2.

1. Bolts retaining the motor on the stand.

2. Bolts retaining the intermediate shaft bearing housing

on the stand.

3. Bolts for the taper bush in the shaft coupling.

Fig. 2. Arrangement 1

Fig. 3. Arrangement 7

Fig. 1.

Guide vane cone

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 2 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

Table 1

Bolt size Tightening torque, Nm

M10 46 ± 2

M12 90 ± 4

M16 195 ± 10

M20 350 ± 15

M24 520 ± 20

The specified tightening torques apply to unlubricated bolts of strength class 8.8

and tightening by means of a torque wrench. The bolts may be pre-tightened by

means of a nut runner to about 3/4 of the specified torque.

Table 2

The tightening torques for Taper-Lock bushes. Each bush

is marked with its number.

Bush No. Tightening Bush No. Tightening

torque, Nm torque, Nm

1008 5,5 2525 48

1108 5,5 3020 90

1210 19,5 3030 90

1310 19,5 3535 113

1610 19,5 4040 169

2012 32 4545 191

2517 48 5050 245

Every three months

1. Check the control function by adjusting the fan manu-

ally a few times between the minimum and maximum

blade settings.

2. Arrangement 7: Lubricate the shaft bearings through

the grease nipples on the fan stand. This frequency of

lubrication is applicable at a maximum temperature of

70°C measured at the outer race of the bearing. For

frequency of lubrication under different conditions,

see Fläkt Woods instructions 141.0, Rolling contact

bearings (can be requisitioned from your nearest ABB

representative). Grease quantity per bearing: 25 g.

3. Check that the fan vibration level is normal and that

no abnormal sounds are heard from the bearings.

If the vibration level, measured on the bearing housing, is

higher than 7 mm/s, determine the cause and take the

necessary remedial action.

Suitable grades of grease

Shell Alvania Grease G3

Alvania EP Grease 2

Statoil Uniway EP 2 N

BP Energrease LS 2

Mobil Mobilgrease HPM

Castrol Spheerol SW 2 EP

Texaco Multifak EP 2

SKF LGEP 2

LGMT 3

Every other year

(from the date when the fan was delivered by Fläkt

Woods AB)

Arrangement 7

Inspect the rubber ring in the shaft coupling for signs of

cracking. Fit a new rubber ring, if necessary.

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 3 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

Fig. 4. EULC, d = 1

1. Blade

2. Screw

3. Screw

4. Washer

5. Shield

6. Screw

7. O-ring

8. Grease nipple

9. Blade mounting

10. Seal

11. Peg

12. Spring

13. Blade spindle

14. Thrust bearing

15. Nut

16. Screw

17. Washer

18. Link

19. Bolt

20. Nut

21. Safety ring

22. Seal

23. O-ring

24. Nut

25. Washer

26. Hub

27. Control disc

28. Bush (Teflon)

29. End disc

30. Washer

31. Bolt

32. Diaphragm

33. Screw

34. End cover

35. Driver

36. Nut

37. Driver guide

38. Washer

39. Spring

40. Washer

41. Rotary coupling Fig. 5. Fan impellerl EULC code suffix d = 1

Feedback cable

Compressed air

hose

Checking and lubricating of EULC fan

impeller, d = 1

(Every other year from the date when the fan was delive-

red by Fläkt Woods)

1. Release the strap around the flexible connection on the

delivery side of the fan and remove the flexible con-

nection from the fan.

2. Remove the bolts retaining the inspection section of the

guide vane section, and remove the inspection section.

3. Disconnect the hose and the feedback cable from the

centre of the impeller (see Fig. 4).

4. Measure the position of the lock nuts (item 36 in Fig.

5) from the end of each driver (35). Remove the nuts

(36), driver guide (37), washers (38) and springs (39).

5. Release the bolted joint (24, 25, 33) and remove the

end cover (34), together with the rotary coupling (41)

and diaphragm (32). NOTE. On certain fan sizes, two

of the bolts (33) are longer than the others. These bolts

determine the minimum setting of the blade angle and

must therefore be fitted in the correct places.

6. Lubricate the blade bearings through the grease nipple

(8). Fill until the grease seeps out at the seal (22). Use

the same type of grease as for the shaft bearings.

7. Examine the bearings of the links (18). If wear or play

is detected, replace the links.

8. Remove the rotary coupling (41) and fit a new coup-

ling.

9. Also fit a new diaphragm (32) together with the end

cover (34) and tighten the bolted joint (24, 25, 33).

NOTE. This bolted joint must be tightened uniform-

ly all round, in order to avoid run-out of the rotary

coupling (41).

10. Fit the springs (39), washers (38), nuts (36) and dri-

ver guide (37).

11. Make sure that the positions of the lock nuts (36) are

the same as before dismantling.

12. Check the radial run-out of the rotary coupling (41).

The maximum permissible total run-out is 0.6 mm.

13. Fit the feedback cable and connect the hose to the

centre of the impeller as shown in Fig 4.

14. Check that the control disc does not tilt and become

jammed in the outer end position.

15. Fit the inspection section of the guide vane section.

Fit the flexible connection into place and clamp it in

position.

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 4 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

1. Blade

2. Screw

3. Screw

4. Washer

5. Shield

6. Screw

7. O-ring

7a. Nut

8. Grease nipple

8a. Counterweight

9. Blade mounting

9a. Washer

10. Seal

11. Peg

12. Spring

13. Blade spindle

14. Thrust bearing

15. Nut

15a. Bolt

16. Screw

17. Washer

18. Link

19. Bolt

20. Nut

21. Safety ring

22. Seal

23. O-ring

24. Nut

25. Washer

26. Hub

27. Control disc

28. Bush (Teflon)

29. End disc

30. Washer

31. Bolt

32. Bolt

33. Bolt

34. End cover

35. Bolt

36. Washer

37. Bush

38. Cover

39. O-ring

40. Control bearing

41. Driver

42. Nut

43. Washer

44. Nut

45. Link mounting

46. Link bearing

47. Nut

Fig. 7. Fan impeller EULC code suffix d = 2

Fig. 6. EULC code suffix d = 2

Turnbuckle

Crank

Control rod

Link

48. Link

49. V-ring

50. Grease nipple

51. Washer

52. Bolt

53. Driver Guide **)

**) Not fitted to certain variants

Checking and lubricating of EULC fan impeller, d = 2

(Every other year from the date when the fan was delivered

by Fläkt Woods)

1. Release the strap around the flexible connection on the

delivery side of the fan and remove the flexible connec-

tion from the fan.

2. Remove the bolts retaining the inspection section of the

guide vane section, and remove the inspection section.

3. Remove the links (48) shown in Fig. 6 and 7.

4. Measure the positions of the lock nuts (item 42 in Fig. 7)

from the end of each driver (35). Remove the nuts (42),

and the driver guide (53).

5. Release the bolted joint (24, 25, 33) and remove the end

cover (34), together with the control bearing (40).

NOTE. On certain fan sizes, two of the bolts (33) are

longer than the others. These bolts determine the mini-

mum setting of the blade angle and must therefore be fit-

ted in the correct places.

6. Lubricate the blade bearings through the grease nipple

(8). Fill until the grease seeps out at the seal (22). Use the

same type of grease as for the shaft bearings.

7. Replace the bearing unit for the control mechanism by

releasing the bolted joint (32, 43, 44) and pressing out

the whole unit. NOTE the V-ring on the outside of the

end cover.

A complete set of spare parts consisting of items 32–40,

43–45, 49 and 50 can be ordered from Fläkt Woods. (See

FPMC-99-20 and FPMC-99-15-1/2 in the spare parts

catalogue.

8. Examine the bearings of the links (18). If wear or play is

detected, replace the links.

9. Fit the end cover (34) with the control bearing (40), and

tighten the bolted joint (24, 25, 33).

10. Fit the lock nuts (42) and the driver guide (53).

11. Check that the positions of the lock nuts (42) are the

same as before dismantling.

12. Check the radial run-out of the link mounting (45).

The maximum permissible total run-out is 0.6 mm.

13. Fit the links (48).

N.B. If the actuator is fitted, run it between the limits of

its travel to check the mechanical maximum and mini-

mum limits of the fan blade angle. Do this with the con-

trol rod disconnected. Use the turnbuckle and the crank

shown in Fig. 6 to carry out any adjustments.

N.B. Adjust the actuator so that the limit switches trip

before the blades have reached their mechanical stops.

14. Fit the inspection section of the guide vane section. Fit

the flexible connection into place and clamp it in posi-

tion.

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 5 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

Fan impeller with manually adjustable blades

(Adjustment cannot be carried out while the

fan is running.)

1. Blade

2. Screw

3. Screw

4. Washer

5. Shield

6. Seal

7. Blade spindle

8. Blade mounting

9. Hub

10. End disc

11. Washer

12. Bolt

Fig. 8

To reset the blade angle, proceed as follows:

1. Remove the flexible connection and the inspection sec-

tion of the guide vane section.

2. Back off the screws (item 2 in Fig. 8).

3. Set the blades to the required angle as shown in Fig. 9.

4. Tighten the screws (item 2 in Fig. 8).

5. Fit the inspection section of the guide vane section.

6. Fit the flexible connection.

Under normal circumstances, the fan impeller needs no

special maintenance.

Fig. 9. Measuring the blade angle

Direction of rotation

Blade cross-section

at root

Hub

Direction of

air flow

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 6 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

Overhauling the EULC fan impeller, code suffix d = 1

(Fig. 4 and 5)

After a longer period of operation, the fan impeller may

need a thorough overhaul, which should be carried out

by Fläkt Woods.

To remove the EULC fan impeller, d = 1

1. Release the strap around the flexible connection on the

delivery side of the fan and remove the flexible connec-

tion from the fan.

2. Remove the bolts retaining the inspection section of

the guide vane section, and remove the inspection sec-

tion.

3. If better accessibility is required, disconnect the hoses

from connections A and C of the positioner, and the

hose and feedback cable from the centre of the impel-

ler (see Fig. 4).

4. Remove the bolts securing the guide vane unit to the

fan casing and remove the guide vane unit.

5. Remove the lock nuts (item 36 in Fig. 5), the driver

guide (37), washers (38) and springs (39).

6. Release the bolted joint (24, 25, 33), and remove the

end cover (34) and the diaphragm (32).

7. Remove the bolt (31), washer (30) and end disc (29).

8. Fit the extractor tool to the hub as shown in Fig. 10

for an impeller with a hub diameter of 500 or 630

mm, and as shown in Fig. 11 for an impeller with a

hub diameter of 800 mm. Remove the impeller.

Fig. 11

Fig. 10

340

160

M 16

To fit the EULC fan impeller, code suffix d = 1

1. Remove the lock nuts (item 36 in Fig. 5), driver

guide (37), washers (38) and springs (39).

2. Release the bolted joint (24, 25, 33) and remove the

end cover (34) and diaphragm (32).

3. Apply a thin coat of molybdenum disulphide (MoS2)

or lubricating grease to the shaft end and to the bore

of the fan hub.

4. Fit the impeller onto the shaft. Fit a press tool into

the tapped hole in the shaft end and press the impel-

ler onto the shaft.

5. Fit the end disc (29), washer (30) and bolt (31).

6. Fit the end cover (34) with the rotary coupling (41)

and diaphragm (32), and tighten the bolted joint (24,

25, 33).

NOTE. This bolted joint must be tightened uni-

formly all round, in order to avoid run-out of the

rotary coupling (41).

7. Fit the springs (39), washers (38), nuts (36) and dri-

ver guide (37).

8. Check that the positions of the lock nuts (35) allow

the blade angle to be set to a maximum (see Fig. 9).

Check that the lock nuts have been threaded on by

equal amounts, so that the control disc will not tilt

and become jammed in to maximum blade angle.

9. Check the radial run-out of the rotary coupling (41).

The maximum permissible total run-out is 0.6 mm.

10. Fit the large part of the guide vane unit. Carefully

centre the centre section in relation to the impeller

hub and tighten the bolted joint at the fan casing.

11. Fit the feedback cable and connect the hose to the

centre of the impeller as shown in Fig. 4, and connect

the hoses to the connections of the positioner as

shown in Fig. 12.

12. Check that the control disc does not tilt and become

jammed in the outer end position.

13. Fit the inspection section of the guide vane section.

Fit the flexible connection into place and clamp it in

position.

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 7 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

Overhauling the EULC fan impeller, code suffix d = 2

(Fig. 6 and 7)

To remove the fan impeller

1. Release the strap around the flexible connection on the

delivery side of the fan and remove the flexible connec-

tion from the fan.

2. Remove the bolts retaining the inspection section of

the guide vane section, and remove the inspection sec-

tion.

3. Remove the links (48) as shown in Fig. 7.

4. Remove the bolts from both ends of the control rod.

5. Release the bolted joint retaining the guide vane unit

on the fan casing and remove the guide vane unit

together with the control rod.

6. Remove the lock nuts (42) and the driver guide (53).

7. Release the bolted joint (24, 25, 33) and remove the

end cover (34), together with the control bearing.

8. Remove the bolt (31), washer (30) and end disc (29).

9. Fit the extractor tool to the hub as shown in Fig. 12

for an impeller with a hub diameter of 500 or 630

mm, and as shown in Fig. 13 for an impeller with a

hub diameter of 800 mm. Remove the impeller.

Fig. 13

Fig. 12

340

160

M 16

To fit the EULC fan impeller, code suffix d = 2

1. Remove the lock nuts and the driver guide (53).

2. Release the bolted joint (24, 25, 33) and remove the

end cover (34), together with the control bearing

(40).

3. Apply a thin coat of molybdenum disulphide (MoS2)

or lubricating grease to the shaft end and to the bore

of the fan hub.

4. Fit the impeller onto the shaft. Fit a press tool into

the tapped hole in the shaft end and press the impel-

ler onto the shaft.

5. Fit the end disc (29), washer (30) and bolt (31).

6. Fit the end cover (34) together with the control bear-

ing (40) and tighten the bolted joint (24, 25, 33).

7. Fit the lock nuts (42) and the driver guide (53).

Check that the positions of the lock nuts allow the

blades to be set to the maximum angle (see Fig. 6).

8. Check the radial run-out of the link mounting (45).

The maximum permissible total run-out is 0.6 mm.

9. Fit the large part of the guide vane unit together with

the control rod. Centre the centre section carefully in

relation to the impeller hub and tighten the bolted

joint to the fan casing.

10. Fit the bolts to both ends of the control rod as shown

in Fig. 6.

11. Fit the links (48).

N.B. If the actuator is fitted, run it between the

limits of its travel to check that these are within the

mechanical maximum and minimum limits of the

blade angle. Do this with the control rod disconnec-

ted. Use the turnbuckle and the crank shown in Fig.

6 to carry out any adjustments.

N.B. Adjust the actuator so that the limit switches

trip before the blades have reached their mechani-

cal stops.

12. Fit the inspection section of the guide vane section.

Fit the flexible connection into place and clamp it in

position.

Recommended tools

Our tool kit, which is available to special order, is recom-

mended for service work on the fan.

The tool kit includes a suitable selection of tools (a total

of 24), vernier calliper, feeler gauges, grease gun, 2 pres-

sure gauges, 3 m of plastic hose, nipples and Teflon tape.

Ordering number: FPAC-99-25.

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 8 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

Connecting the positioner

(applies only to the EULC with pneumatic control)

Use a 6 mm o.d./4 mm i.d. plastic hose to connect the

positioner as shown in Fig. 14. For particulars of the con-

trol pressure, see the adjacent table. NOTE that only air

of instrument quality may be connected to the positioner.

Air of instrument quality contains particles no larger

than 10 mm and has a dew point of -20°C or below. The

position is preset at the factory so that the blade angle

will be a minimum at a signal pressure of 21 kPa (3 psi)

and a maximum at 105 kPa (15 psi).

Fig. 14

A. 21–105 kPa (3–15 psi) signal

pressure from the controller

B. Output to the impeller

C. Actuating pressure. For pressure necessary,

see the table below (350 kPa max.)

D. Zeroing screw

E. Screw for stroke factor

G. Flapper

H. Feedback arm

J. Feedback cable

Actuating pressure

Size– n = 980 r/min n = 1470 r/min

hub Nbr. of blades d = Nbr. of blades d =

b–c 8 8 9

EULC – actuating pressure necessary, kPa

0–5

5–5

1–5 120 200 –

6–5

2–5

7–5

3–5

8–5 150 350 –

4–5

9–5

1–6

6–6

2–6

7–6 150 350 –

3–6

8–6

4–6

9–6

3–8

8–8 – – 250

4–8

9–8

Adjusting the positioner

1. Set the signal pressure at tapping A to 21 kPa (3 psi).

2. Adjust zeroing screw D so that when the blades are at

minimum angle, they will start to open at 21 kPa (3

psi) when the signal pressure is increasing.

3. Set the signal pressure at tapping A to 105 kPa (15

psi).

4. Adjust stroke factor screw E so that when the blades

are at maximum angle, they will start to close at 105

kPa (15 spi) when the signal pressure is falling.

Note the following when adjusting the positioner:

a) Follow the instructions in points 2 and 4 above when

the fan is running.

b) The distance between the stroke factor segment and

the stop pad must be 2 mm, measured with the blades

set to the minimum angle.

Caution: The segment must not come into contact

with the stop pad. The positioner may otherwise be

damaged.

c) The travel of the positioner feedback arm should be

symmetrical about the vertical line between the maxi-

mum and minimum angle settings.

d) The feedback cable must run correctly across the guide

pulleys.

Amplification and damping

The positioner includes adjusting screws for the amplifi-

cation and damping. The response of the positioner to a

certain change in signal pressure can be adjusted by

means of the amplification screw. The damping screw is

used to adjust the output pressure of the positioner and

thus the response speed of the actuator. The amplifica-

tion and damping are preset at the factory and need not

normally be adjusted. If adjustment is carried out, the

zero point and stroke factor must also be re-adjusted.

Functional check

Check the operation of the positioner as follows:

1. Disconnect the hose from connection B.

2. Remove the positioner cover.

3. Make sure that there is actuating pressure at connec-

tion C.

4. Move the flapper between the nozzles in a downward

direction, and air should then flow from connection B.

5. Move the flapper in the opposite direction, and the air

flow should then cease.

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 9 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

Inverse action of the positioner

The positioner used for EULC fans, d = 1, is direct-

acting, i.e. the blade angle increases with increasing pres-

sure to the positioner. If inverse action is required, the

positioner can be modified (see Fig. 15).

1. Remove the positioner, together with its bracket and

air connections, and disconnect the cable.

2. Remove the torsion spring at the rear of the positioner

and replace it by spring FSAC-99-10-2.

3. Secure the positioner through the two holes located

250 mm below the original mounting holes, and turn

the positioner through 180°, so that the feedback arm

points upwards.

4. Connect the cable and air connection and turn the

reconnection plate F to position U.

5. Adjust as described on the preceding page, but make

sure that the blades close on an increase in signal pres-

sure and open on a decrease in signal pressure.

Fig. 15. Positioner fitted for inverse action

A. Signal pressure from controller, 21–105 kPa (3–15 psi).

D. Zeroing screw

E. Screw for stroke factor

F. Reconnection plate

Recommended spare parts for the EULC, d = 1

1 rotary coupling (item 41 in Fig. 5) per fan

1 set of links (18) (quantity same as number of blades)

1 diaphragm (32) per fan

1 rubber ring for shaft coupling (applies to Arrangement

1 positioner for every four fans

Recommended spare parts for the EULC, d = 2

1 control assembly (items 32 + 35–40 and 43–45, 49 and

50 in Fig. 7 per fan.

1 set of links (18) (quantity same as number of blades)

1 rubber ring for shaft coupling (applies to Arrangement

If the system includes a larger number of EULC fans, it

may be advisable to increase the number of spare parts by

keeping in stock items such as complete impellers,

motors, actuators, shaft bearings and shaft couplings.

Touching-up paint

The fan is painted at the factory with quick-drying,

alkyd-based primer and top coat, International

Primertäck 42 866 HB. The colour is NCS 3060-R80B.

The same paint type should be used for all touching-up.

EULC Axial-flow fan

Fläkt Woods 3183 GB 03.01 10 Specifications are subject to alteration without notice

EU Air Handling Unit MAINTENANCE

Fitness test

Measured values

Motor current..........................................................A

Blade Pitch ...............................................................°

Control signal, d = 1/d = 2 .........................kPa/V/mA

Actuating pressure, d = 1......................................kPA

Vibration in the bearings

Specified values

Total pressure .........................................................Pa

Air flow ..............................................................m3/s

Max. blade pitch.......................................................°

Fan speed.............................................................rpm

Horizontal Vertical Axial, Foot, vertical arr

mm/sek RMS mm/sek RMS mm/sek RMS R T A

Condition of the bearings

Temp °C Noise Other

Other checkpoints

Control: Lubrication: Anti-vibration mountings:

d = 1 feedbakc cable: OK/Adjust Motor bearings Condition: OK/Replace

d = 2 control rod: OK/Adjust Shaft bearings Fasteners: OK/Remarks

Other accessories:

Other ..................................

...........................................

Carried out on:

Sign.:

(Skiss)

FläktGroup EULC Axial flow fan Installation guide

FläktGroup EULC Axial flow fan Installation guide

FläktGroup EULC Axial flow fan Installation guide

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