Design Documents (Shaft Couplings)

Perform calculations according to the following design procedure in order to select the proper shaft coupling.

Design Procedure

  1. Calculate the Design Torque
  2. Select the Size
  3. Check the Maximum Shaft Hole Diameter and Maximum Rotation Speed
  4. Conclusion

Selection Example

Motor:

Output 15 kW
Standard motor (4-pole, 60 Hz), 1,750 min-1
Shaft diameter and key: φ42, 12 x 8

Driven device:

Centrifugal pump, operates 8 hours per day
Shaft diameter and key: φ35, 10 x 8

Calculate the Design Torque

Select the overload factor Ko from [Table 1] and obtain the design torque.

T = 9550・PN・Ko
n

T: Design torque (N・m)
PN: Design power (kW)
Ko: Overload factor [Table 1]
n: Rotational frequency(min-1)

Design Torque Calculation Example

According to [Table 1], overload factor Ko = 1.0
Therefore,

Design torque T=9550×15×1.0= 81.9N・m
1750

Select the Size

Select a shaft coupling with a maximum torque (rated torque for Sure-Flex®) that is equal to or greater than the design torque T from each performance table.
Make sure to select the ideal shaft coupling type taking environment, cost, etc. into consideration.

Size Selection Example

Here, the flexible flanged shaft coupling is used.

Since the design torque is 81.9 N・m,
FCL-140
FCLS-140
are selected.

Check the Maximum Shaft Hole Diameter and Maximum Rotation Speed

Make sure that both the maximum shaft hole diameter and the maximum rotation speed are not less than those of the design conditions. If either or both of the maximum shaft hole diameter and the maximum rotation speed do not satisfy the conditions, select a higher model number.

Maximum Shaft Hole Diameter and Maximum Rotation Speed Checking Example

The maximum shaft hole diameter of FCL-140 is
Bolt side: φ38<φ42 (motor shaft diameter)
Bushing side: φ35=φ35 (driven device shaft diameter)
so the design conditions are not satisfied.

Using the same method, the max. shaft hole diameter of FCLS-140 is
Bolt side: φ42=φ42 (motor shaft diameter)
Bushing side: φ38>φ35 (driven device shaft diameter)
so the design conditions are satisfied.

The max. shaft hole diameter of the higher model number FCL-160 is
Bolt side: φ45>φ42 (motor shaft diameter)
Bushing side: φ38>φ35 (driven device shaft diameter)
so the design conditions are satisfied.

The maximum rotational frequency is
FCL-160 :4000min-1 > 1750min-1 
FCLS-140 :6000min-1 > 1750min-1 
so the design conditions are satisfied.

Therefore, either
FCL-160
FCLS-140
will be used.

Conclusion

Finally, confirm that the design conditions are satisfied based on the dimensions/performance tables.
Tables 3 and 4 are selection tables that are used when a general-purpose low-voltage three-phase squirrel-cage induction motor is the motor.
The shaft coupling can be easily selected without relying on the above design steps.

Conclusion

FCL-160
FCLS-140
Use either of the above.

[Table 1] ● Flanged shaft coupling overload factor: Ko

Driven Device Motor
Machine Used Electric motor or steam turbine Steam engine or 4-cylinder or more gasoline engine Diesel engine or gas engine
Daily operating time (hours)
8~10 16~24 8~10 16~24 8~10 16~24
Uniform load (no reverse rotation / low torque startup) Fluid mixer, centrifugal blowers/exhaust fan (up to 10PS), centrifugal pump, light-load conveyor, electric generator, worm gear reducer 1.0 1.5 1.5 2.0 2.0 2.5
Uneven load (no reverse rotation / normal shock) Conveyor, hoist, elevator, line shaft, hole mill, kiln 1.5 2.0 2.0 2.5 2.5 3.0
Heavy load with impact (with peak / with reverse rotation / full load startup) Reciprocating compressor, press, hammer mill, crusher, reciprocating pump, marine propeller 2.0 2.5 2.5 3.0 3.0 3.5

[Table 2] ● FCL (FC200) Selection Table

50Hz 2-pole・2850min-1 4-pole・1425min-1 6-pole・950min-1 8-pole・725min-1
Motor Rated Output
(kW)
Shaft Diameter
(mm)
Torque
(N・m)
Overload Factor:Ko Shaft Diameter
(mm)
Torque
(N・m)
Overload Factor:Ko Shaft Diameter
(mm)
Torque
(N・m)
Overload Factor:Ko Shaft Diameter
(mm)
Torque
(N・m)
Overload Factor:Ko
1.0 1.5 2.0 1.0 1.5 2.0 1.0 1.5 2.0 1.0 1.5 2.0
0.2 (11) 0.683 90 90 90 (11) 1.37 90 90 90
0.4 (14) 1.37 90 90 90 (14) 2.73 90 90 90 (19) 4.1 90 90 90
0.75 19 2.56 90 90 90 19 5.12 90 90 90 24 7.69 100 100 100
1.5 24 5.12 100 100 100 24 10.2 100 100 100 28 15.4 112 112 112
2.2 24 7.51 100 100 100 28 15 112 112 112 28 22.5 112 125 125
3.7 28 12.6 112 112 112 28 25.3 112 125 125 38 37.9 140 140 140
5.5 38 18.8 140 140 140 38 37.6 140 140 140 38 56.4 140 140 140
7.5 38 25.6 140 140 140 38 51.2 140 140 140 42 76.9 160 160 160
11 42 37.6 160 160 160 42 75.1 160 160 160 42 113 160 160 180
15 42 51.2 160 160 160 42 102 160 160 180 (48)・55 154 (180)・200 200 200
18.5 42 63.2 160 160 160 48 126 180 180 200 55 190 200 200 200
22 48 75.1 180 180 180 (48)・55 150 (180)・200 (180)・200 200 (55)・60 225 (200)・224 (200)・224 224
30 55 102 200 200 200 55 205 200 200 200 60 307 224 224 250 65 403 250 250 250
37 55 126 200 200 200 60 253 224 224 224 (60)・65 379 (224)・250 250 250 75 497 280 280 280
45 55 154 200 200 200 60 307 224 224 250 65 461 250 250 280 75 604 280 280 280
55 55 188 200 200 200 65 376 250 250 250 75 564 280 280 280 85 739 315 315 315
75 55 256 200 200 75 512 280 280 280 75 769 280 280 315 85 1010 315 315 315
90 55 307 200 224 75 615 280 280 280 85 922 315 315 315 95 1210 355 355 355
110 55 376 200 85 751 315 315 315 85 1130 315 315 315 95 1480 355 355 355
132 55 451 224 85 902 315 315 315 95 1350 355 355 355
160 55 547 95 1090 355 355 355 95 1640 355 355 355
200 55 683 95 1370 355 355 355
60Hz 2-pole・3450min-1 4-pole・1750min-1 6-pole・1160min-1 8-pole・870min-1
0.2 (11) 0.56 90 90 90 (11) 1.11 90 90 90
0.4 (14) 1.13 90 90 90 (14) 2.23 90 90 90 (19) 3.36 90 90 90
0.75 19 2.12 90 90 90 19 4.17 90 90 90 24 6.29 100 100 100
1.5 24 4.23 100 100 100 24 8.34 100 100 100 28 12.6 112 112 112
2.2 24 6.21 100 100 100 28 12.2 112 112 112 28 18.5 112 112 125
3.7 28 10.4 112 112 112 28 20.6 112 112 125 38 31.1 140 140 140
5.5 38 15.5 140 140 140 38 30.6 140 140 140 38 46.2 140 140 140
7.5 38 21.2 140 140 140 38 41.7 140 140 140 42 62.9 160 160 160
11 42 31 160 160 160 42 61.2 160 160 160 42 92.3 160 160 160
15 42 42.3 160 160 160 42 83.4 160 160 160 (48)・55 126 (180)・200 (180)・200 200
18.5 42 52.2 160 160 160 48 103 180 180 180 55 155 200 200 200
22 48 62.1 180 180 180 (48)・55 122 (180)・200 (180)・200 200 (55)・60 185 (200)・224 (200)・224 (200)・224
30 55 84.7 55 167 200 200 200 60 252 224 224 224 65 336 250 250 250
37 55 104 60 206 224 224 224 (60)・65 311 (224)・250 250 250 75 414 280 280 280
45 55 127 60 250 224 224 224 65 378 250 250 250 75 504 280 280 280
55 55 155 65 306 250 250 250 75 462 280 280 280 85 615 315 315 315
75 55 212 75 417 280 280 280 75 629 280 280 280 85 839 315 315 315
90 55 254 75 501 280 280 280 85 755 315 315 315 95 1010 355 355 355
110 55 310 85 612 315 315 315 85 923 315 315 315 95 1230 355 355 355
132 55 372 85 734 315 315 315 95 1110 355 355 355
160 55 451 95 890 355 355 355 95 1340 355 355 355
200 55 564 95 1110 355 355 355

● Numbers in the table represent the size. The model number is displayed by adding "FCL" before these numbers.
●The shaft end dimensions depend on JEM1400-1991 (Dimensions of general-purpose low-voltage three-phase squirrel-cage induction motors).
●Numbers in parentheses indicate fully closed motors.

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