Technical Timing

Fzul

ZB1 LBZ1

dk1do1

Ze

n1

Fu, v

n2

do2

tdk2

Centre distance a (mm)Acceleration torque MB (Nm)Acceleration time tB (s)Bore d (mm)Density (kg/dm3)Torque M (Nm)RPM n (min-1)Outside diameter dK (mm)Power P (kW)Moment of inertia J (kgm2)Belt length LB (mm)Ratio iAllowable tensile load Fzul (N)Belt width b (cm)

Pulley width B (mm)Pitch t (mm)Velocity v (m/s)Peripheral force FU (N)Angular velocity ! (s-1)Pitch circle diameter dO (mm)No. of teeth when i = 1 zNo. of teeth of small pulley z1No. of teeth of large pulley z2No. of teeth on the belt zBNo. of teeth in mesh zePCD (small pulley) do1PCD (large pulley) do2

Exact CTS when i = 1

ZB – Z1 a = x t

2

Exact CTS when i ! 1

(do2 — do1)2a = K + K2 –

8

LB K = – .392699 (do2 + do1)

4

PCD mmNo. of Teeth x Pitch mm

do mm ="

TIMING BELTS FORMULAE, TERMS & DEFINITIONS

"

PCD (2)

PCD (1) CTSIf the number of teeth on the two mating pulleys/sprocketsare within 5 teeth of each other then the belt/chain lengthcan be calculated as follows:-

TOTAL No. of TEETHTBL

or links =PITCH OF PULLEY (SPROCKET) mm

(PCD (1) + PCD (2)TBL = + (2 x CTS)

0.6366

TOTAL BELT LENGTH(Similar sized pulleys)

( )

(in mm)

(in mm)

(in mm)

TIMIN

GB

ELTS|

TE

CH

NIC

AL

SE

CTIO

N

771Telephone +44(0)1246 268080 Fax +44(0)1246 260003Unit 14, Foxwood Industrial Park, Foxwood Road, Chesterfield, Derbyshire S41 9RN

Belt length with i = 1

Peripheral force Torque Power

Angular velocity Rpm Velocity

Mass moment of inertia

Only the units listed above should be used in the formulae, as they areapproved SI units. The unit of force, the Newton, is very important: 1N is theforce required to accelerate a body with a mass of 1kg to 1m/s2. 1N = kg • 1m/s2.

TIMING BELTS FORMULAE, TERMS & DEFINITIONS

2 • 103 • MFU =

do

19,1 • 106 • P=

n • do

103 • P=

v

do • FuM = 2 • 103

9,55 • 103 • P=

n

do • P=

2 • v

Belt length with i # 1

Acceleration torque

" • n! = 30

19,1 • 103 • vn =

do

do • nv =

19,1 103

M • nP =

9,55 • 103

Fu • do • n=

19,1 • 106

Fu • v =

103

LB = 2 a + " • do= 2 a + z • t

t 1 (Z2 – Z1) t 2LB # (Z2 + Z1) + 2 a +

2 4 a "[ ]

J = 98,2 • 10–15 • B • • (dk4 – d4)$ J • $n

MB = 9,55 • tB

FORCETORQUEPOWERCENTRIFUGAL FORCE

1kp = 1 kg • 9.81 m/s2 = 9.81 N = 1 daN

1kpm = 9.81 kgm2/s2 = 9.81 Nm = 1 daNM

1HP = 75 kpm/s = 0.736 kW

1 [GD2] = 4 [J] when GD2 in kpm and J in kgm2

CONVERSION OF NON-STANDARD UNITS

TIM

ING

BEL

TSTE

CH

NIC

AL S

EC

TIO

N |

772 Telephone +44(0)1246 268080 Fax +44(0)1246 260003Unit 14, Foxwood Industrial Park, Foxwood Road, Chesterfield, Derbyshire S41 9RN

BELT LIFE: The expected belt life is between 10,000 and 15,000 hours, if installedcorrectly and not overloaded.

Fu = Fu spez • Ze • b in N

Mspez • Z1 • Ze • b in NmM =

100

Pspez • Z1 • Ze • b in kWP =

1000

Fspez Specific peripheral force in Ncm

Mspez Specific torque in Ncmcm

Pspez Specific power in Wcm

The belt width (in cm) required to transmit known peripheral force FU , torque M or power Pwithout exceeding the maximum allowable tooth shear strength is calculated using any of thefollowing formulae and the values on the following pages:-

FUb = in cmze • FUspez

100 • Mb = in cm

z1 • ze • M spez

1000 • Pb = in cm

z1 • ze • Pspez

FU = Peripheral force in N

M = Torque in NmP = Power in kWz1 = No. of teeth in small pulleyze = No. of teeth in mesh (Ze max= 12)

z1 ( z2 — z1) • tze = • arc cos 180 2 % a

z1 = No. of teeth in small pulleyz2 = No. of teeth in large pulley

t = Pitch in mma = Centre distance in mm

The following safety factors should be employed with speed-up drives:

Ratio i = over 1 to 1.5 Safety factor S = 1.1i = over 1.5 to 2.5 S = 1.2i = over 2.5 S = 1.3

The size of a Synchroflex Timing Belt is correctly determined when the permissible tooth shear strength, tensile loadsand flexibility limits are not exceeded under the worst conditions. Safety factors are only necessary in speed-up drives.It is important that the peak loads acting on a drive are known, i.e. that they are correctly assessed by the designer. In apositive drive transient shock loads will have an effect on the whole drive. Some helpful hints on this subject are:-Normal operating conditions : The timing belt should be designed to cope with rated working loads and conditions.Rated working loads are defined as the operating conditions under which the drive is expected to transmit torque orpower based on the rated speed and normal running conditions.Start-up conditions : (a) Driver: the max. start-up torque of the motor must be taken into account. The start-up torqueon a three phase motor, for example, can be 2 - 2.5 times the running torque. (b) Driven: it is also important to considerpossible break-away torque acting on the timing belt under start-up conditions. Check belt loading conditions (a) or (b)at n = 0 rpm.Braking : It is necessary to determine whether loads induced by braking will affect the timing belt. It is quite possible thatthese loads may exceed those already present due to start-up and normal running conditions. Under braking conditionstorque reversal should be taken into consideration and that if a torque reversal occurs under braking then a speedreduction would change to a speed-up drive.Shock Loads : If shock loads are present it would be necessary to increase the belt width factor by 1.3.Inertial Masses : Inertial massed generally help in the smooth running of drives. However it is very important to checkthat extra loads these inertial masses are exerting on the timing belt under acceleration and braking conditions.

TIMING BELT CALCULATIONS

Belt width required in cm = b Drive load capacity (with known belt width cm)

Peripheral force

Torque

Power

Speed-up drives

TIMIN

G B

ELTS| TE

CH

NIC

AL S

EC

TIO

N


Speed of the small pulley nk (min-1)

AT20T20

AT10T10

AT5T5

T2.5

Des

ign

Pow

er P

B(K

W)

Graph 3.2

15000

20000

10000

6000

10

500400300

200

1008060504030

20

1086543

2

10.80.60.50.40.3

0.2

0.10.080.060.050.04 20 40 60 80 100

200

400

600

1000

2000

4000

H

L

XL

MXL, MP

BELT SELECTION GRAPHPOWER RATING GRAPH FOR SECTIONSELECTION AND MAX. BELT SPEEDS

TIM

ING

BEL

TSTE

CH

NIC

AL S

EC

TIO

N |


FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

T2.5 T2.5

020406080

100150200300400500600700730800900

100011001200130014001460150016001700180019002000

9.038.728.488.288.107.957.647.397.016.716.486.286.116.075.975.835.715.615.515.415.335.285.255.175.105.044.974.91

0.3590.3470.3370.3290.3220.3160.3040.2940.2790.2670.2580.2500.2430.2410.2370.2320.2770.2230.2190.2150.2120.2100.2090.2060.2030.2000.1980.195

0.0000.0070.0140.0210.0270.0330.0480.0620.0880.1120.1350.1570.1780.1850.1990.2190.2380.2570.2750.2930.3110.3210.3280.3450.3610.3780.3940.409

22002400250026002800288030003200340036003800400045005000550060006500700075008000850090009500

1000012000150001800020000

4.804.704.654.604.514.484.434.364.284.224.154.093.953.823.713.603.513.423.333.263.183.113.052.992.772.502.282.15

0.1910.1870.1850.1830.1800.1780.1760.1730.1700.1680.1650.1630.1570.1520.1480.1430.1400.1360.1330.1300.1270.1240.1210.1190.1100.0990.0910.086

0.4400.4700.4840.4990.5270.5380.5540.5810.6070.6320.5670.6820.7400.7960.8500.9010.9500.9971.0421.0861.1281.1681.2071.2451.3841.5611.7081.791

439

665

10117

16195

T2.5 Belt Width in mmNewtons

1015mm

1815mm

T2.5Minimum No. of Teeth on pulley.Minimum DIA of flat tension pulley running on the belt teethMinimum No. of Teeth on timing pulleys for double sided belts T2.5 DLMinimum DIA of flat tension pulley running on belt back

Type of Teeth

without contraflexure

with contraflexure

TOOTH SHEAR STRENGTHT2.5 TIMING BELT/PULLEY2.5mm PITCHTOOTH SHEAR STRENGTH

TENSION MEMBER TENSILE STRENGTH

FLEXIBILITYAllowable tensile load on belt cross section Fzul in N.

MAX. BELT CAPACITYMax. power 0.5kwMax. speed 40000 RPMMax. recommended belt speed 80m/s

TIMIN

G B

ELTS| TE

CH

NIC

AL S

EC

TIO

N



FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

T5 T5

020406080

100150200300400500600700730800900

100011001200130014001460150016001700180019002000

24.0023.3822.8622.4122.0121.6520.9020.2819.3018.5517.9317.4116.9616.8316.5616.2015.8815.5815.3115.0614.8314.6914.6114.4014.2114.0313.8513.69

1.9101.8611.8191.7831.7511.7231.6631.6141.5361.4761.4271.3851.3491.3391.3181.2891.2631.2401.2181.1981.1801.1691.1621.1461.1311.1161.1021.089

0.0000.0390.0760.1120.1470.1800.2610.3380.4830.6180.7470.8700.9891.0241.1041.2151.3231.4281.5311.6321.7301.7881.8261.9202.0132.1042.1932.281

22002400250026002800288030003200340036003800400045005000550060006500700075008000850090009500

1000012000150001800020000

13.3813.1012.9612.8412.5912.5012.3712.1611.9611.7711.5911.4211.0310.6810.3610.079.819.569.339.118.918.728.548.377.757.006.396.03

1.0651.0421.0321.0211.0020.9950.9840.9670.9510.9360.9220.9090.8780.8500.8250.8020.7800.7610.7420.7250.7090.6940.6790.6660.6170.5570.5080.480

2.4532.6192.7012.7812.9383.0003.0923.2413.3883.5303.6703.8074.1364.4504.7505.0375.3125.5775.8316.0766.3126.5406.7596.9707.7528.7529.582

10.055

6180

10330

16570

25930

321200

501920

752940

1003930

T5 Belt Width in mmNewtons

1030mm

1530mm

T5Minimum No. of Teeth on pulley.Minimum DIA of flat tension pulley running on the belt teethMinimum No. of Teeth on timing pulleys for double sided belts T5 DLMinimum DIA of flat tension pulley running on belt back

Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHT5 TIMING BELT/PULLEY5mm PITCHTOOTH SHEAR STRENGTH



MAX. BELT CAPACITYMax. power 5kwMax. speed 40000 RPMMax. recommended belt speed 80m/s

TE

CH

NIC

AL S

EC

TIO

N |

TIM

ING

BEL

TS

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

AT5 AT5

020406080

100150200300400500600700730800900

100011001200130014001460150016001700180019002000

35.334.934.534.133.833.532.732.030.929.829.028.227.527.326.826.325.725.224.824.323.923.723.523.222.822.522.221.9

2.8072.7752.7452.7172.6892.6632.6032.5492.4552.3752.3052.2422.1872.1712.1362.0902.0472.0071.9701.9361.9031.8851.8721.8431.8161.7891.7641.740

0.0000.0570.1150.1710.2250.2790.4090.5340.7710.9951.2071.4091.6031.6601.7891.9692.1442.3122.4762.6352.7902.8812.9413.0893.2323.3733.5103.645

22002400250026002800288030003200340036003800400045005000550060006500700075008000850090009500

10000

21.320.820.520.319.819.719.419.018.618.317.917.616.916.215.615.014.514.013.513.112.712.312.011.6

1.6951.6541.6341.6151.5791.5651.5451.5131.4831.4541.4271.4011.3421.2881.2391.1941.1521.1131.0771.0431.0110.9810.9530.925

3.9064.1564.2784.3974.6304.7204.8545.0705.2805.4865.6795.8706.3226.7427.1347.4997.8418.1618.4608.7409.0029.2489.4779.690

6-

10490

16840

251400

321890

503010

754620

1006160

AT5 Belt Width in mmNewtons

1525mm

2060mm

AT5Minimum No. of Teeth on pulley.Minimum DIA. of flat tension pulley running on the belt teethMinimum No. of Teeth on pulley.Minimum DIA. of flat tension pulley running on belt back

Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHAT5 TIMING BELT/PULLEY5mm PITCHTOOTH SHEAR STRENGTH



TIMIN

G B

ELTS| TE

CH

NIC

AL S

EC

TIO

N


MAX. BELT CAPACITYMax. power 15kwMax. speed 40000 RPMFlank Play 0.2mmMax. recommended belt speed 80m/s

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

T10 T10

020406080

100150200300400500600700730800900

100011001200130014001460150016001700180019002000

50.5049.0047.7046.6045.6044.8042.9041.4039.1037.2035.7034.4033.3033.0032.4031.5030.7030.0029.3028.7028.2027.8027.6027.1026.6026.2025.8025.40

8.047.807.607.427.277.136.836.596.225.925.685.485.315.265.155.014.894.774.674.574.484.434.404.324.244.174.104.04

0.0000.1630.3180.4660.6090.7461.0731.3811.9532.4812.9763.4443.8904.0204.3164.7255.1195.4995.8676.2236.5696.7726.9057.2327.5517.8618.1648.459

22002400250026002800288030003200340036003800400045005000550060006500700075008000850090009500

10000

24.6023.9023.6023.3022.7022.5022.2021.6021.2020.7020.3019.9018.9018.1017.3016.6015.9015.3014.8014.2013.7013.3012.8012.40

3.923.813.763.713.623.583.533.453.373.303.233.163.012.872.752.642.542.442.352.272.192.112.041.98

9.039.589.84

10.1010.6010.8011.0811.5511.9912.4212.8413.2414.1815.0515.8416.5817.2617.8818.4618.9919.4719.9220.3320.70

161100

251800

322300

503800

755800

1007800


1260mm

2060mm

T10

Minimum No. of Teeth on pulley.Minimum DIA of flat tension pulley running on the belt teethMinimum No. of Teeth on timing pulleys for double sided belts t20 DLMinimum DIA of flat tension pulley running on belt back

Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHT10 TIMING BELT/PULLEY10mm PITCH

Allowable tensile load on belt cross section Fzul in N.

TOOTH SHEAR STRENGTH


FLEXIBILITY


TIM

ING

BEL

TSTE

CH

NIC

AL S

EC

TIO

N |


FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

AT10 AT10

020406080

100150200300400500600700730800900

100011001200130014001460150016001700180019002000

73.572.471.470.569.668.766.865.062.159.557.455.553.753.352.250.849.548.347.246.245.244.644.343.442.641.841.040.3

11.7011.5311.3711.2111.0710.9410.6310.359.889.489.138.838.558.488.318.087.887.697.517.357.197.107.046.916.786.656.536.42

0.0000.2410.4760.7050.9281.1451.6692.1683.1033.9694.7805.5456.2706.4816.9617.6208.2518.8579.44010.00110.54310.85911.06611.57212.06212.53612.99613.442

22002400250026002800288030003200340036003800400045005000550060006500700075008000850090009500

10000

39.037.837.236.635.535.134.533.632.731.931.130.328.526.925.524.223.021.820.819.818.818.017.016.3

6.206.015.925.835.665.595.505.355.205.074.944.824.544.294.063.853.653.473.303.153.02.862.722.60

14.3015.1015.4915.8616.5816.8617.2717.9218.5319.1119.6720.2021.4022.4623.3824.1824.8725.4625.9626.3626.6926.9327.1027.20

253500

324750

507750

7512000

10016000

15024500


1550mm

25120mm

AT10

Minimum No. of Teeth on pulley.Minimum DIA of flat tension pulley running on the belt teethMinimum No. of Teeth on pulley.Minimum DIA of flat tension pulley running on belt back

Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHAT10 TIMING BELT/PULLEY10mm PITCH

Allowable tensile load on belt cross section Fzul in N.



FLEXIBILITY

TIMIN

G B

ELTS| TE

CH

NIC

AL S

EC

TIO

N



FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

T20 T20

020406080

100150200300400500600700730800900

100011001200130014001460150016001700180019002000

101.598.195.392.890.788.784.681.275.971.868.465.663.162.460.959.057.255.654.252.851.550.850.349.248.247.246.245.3

32.231.230.329.528.928.226.925.924.222.921.820.920.119.919.418.818.217.717.216.816.416.216.015.715.315.014.714.4

0.0000.6541.2711.8562.4172.9574.2295.4157.5919.573

11.40513.11714.72815.19416.25217.70019.08020.39921.66322.87524.04124.71925.16226.24327.28628.29229.26430.204

22002400250026002800288030003200340036003800400045005000550060006500

43.642.141.440.739.338.838.137.035.934.933.933.030.828.927.225.624.2

13.913.413.212.912.512.412.111.811.411.110.810.59.89.28.68.17.7

31.9933.6734.4735.2436.7237.2938.1139.4240.6641.8242.9143.9446.2448.2149.9051.2052.40

324750

507750

7512000

10016000

15024500

15120mm

25120mm

T20

Minimum No. of Teeth on pulley.Minimum DIA of flat tension pulley running on the belt teethMinimum No. of Teeth on timing pulleys for double sided belts T20 DLMinimum DIA of flat tension pulley running on belt back

Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHT20 TIMING BELT/PULLEY20mm PITCH






TIM

ING

BEL

TSTE

CH

NIC

AL S

EC

TIO

N |


FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

AT20 AT20

020406080

100150200300400500600700730800900

100011001200130014001460150016001700180019002000

147.0144.2141.7139.3137.0134.9130.1125.8118.5112.4107.2102.698.597.494.891.588.485.682.980.578.276.876.073.972.070.168.466.7

46.845.945.144.343.642.941.440.037.735.834.132.731.431.030.229.128.127.226.425.624.924.524.223.522.922.321.821.2

0.0000.9621.8892.7863.6544.4976.5048.388

11.85114.98817.86220.51622.98223.68925.28427.44129.46631.37333.17134.86936.47537.39737.99439.43340.79642.08743.31044.469

22002400250026002800288030003200340036003800400045005000550060006500

63.660.759.358.055.554.553.150.948.846.845.043.239.035.332.028.926.0

20.219.318.918.417.717.316.916.215.514.914.313.712.411.210.19.28.2

46.6048.5249.4050.2351.7552.3153.1054.2855.3156.1956.9357.5558.5658.8960.6061.7062.40

326750

5011250

7517550

10023850

15036450


18120mm

25180mm

AT20


Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHAT20 TIMING BELT/PULLEY20mm PITCH




TIMIN

G B

ELTS| TE

CH

NIC

AL S

EC

TIO

N



FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

MP, MXL MP, MXL

020406080

100150200300400500600700730800900

100011001200130014001460150016001700180019002000

6.586.366.186.035.905.795.565.385.104.894.724.584.454.424.354.254.164.084.013.943.883.853.823.773.723.673.623.58

0.2130.2060.2000.1950.1910.1870.1800.1740.1650.1580.1530.1480.1440.1430.1410.1370.1350.1320.1300.1280.1260.1240.1240.1220.1200.1190.1170.116

0.0000.0040.0080.0120.0160.0200.0280.0360.0520.0660.0800.0930.1060.1090.1180.1300.1410.1520.1630.1740.1840.1900.1940.2040.2140.2240.2330.242

22002400250026002800288030003200340036003800400045005000550060006500700075008000850090009500

1000012000150001800020000

3.503.423.393.353.293.263.233.173.123.073.022.982.882.782.702.632.562.492.432.372.322.272.222.182.021.821.661.57

0.1130.1110.1100.1080.1060.1060.1040.1030.1010.0990.0980.0960.0930.0900.0870.0850.0830.0810.0790.0770.0750.0730.0720.0700.0650.0590.0540.051

0.2610.2780.2870.2950.3120.3180.3280.3440.3590.3740.3890.4040.4380.4720.5030.5330.5620.5900.6170.6430.6680.6920.7150.7370.8190.9241.0111.061

1015mm

1815mm

MPMXL


Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHMP, MXL TIMING BELT/PULLEY0.08” PITCH

439

665

10117

16195

MP, MXL Belt Width in mmNewtons




MAX. BELT CAPACITYMax. power 0.5kwMax. speed 40,000 RPMMax. recommended belt speed 80m/s

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FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

XL XL

020406080

100200300400500600700800900

10001100120013001400150016001700180019002000

24.4023.8023.2022.8022.4022.0020.6019.6318.8618.2317.7017.2416.8316.4716.1415.8415.5715.3115.0714.8514.6414.4514.2614.0813.91

1.9731.9221.8791.8421.8091.7801.6671.5871.5251.4741.4311.3941.3611.3321.3051.2811.2591.2381.2191.2011.1841.1681.1531.1391.125

0.0000.0400.0790.1160.1520.1860.3490.4980.6390.7720.8991.0221.1401.2551.3671.4751.5821.6851.7871.8861.9842.0802.1702.2702.360

2200240026002800300032003400360038004000450050005500600065007000750080009000

10000

13.6013.3113.0812.8012.5712.3612.1611.9611.7811.6111.2110.8610.5410.249.979.729.499.278.868.51

1.1001.7061.0551.0351.0170.9990.9830.9670.9530.9390.9070.8780.8520.8280.8060.7860.7670.7490.7170.688

2.5302.7102.8703.0603.1903.3503.5003.6503.7903.9304.2704.6004.9105.2005.4905.7606.0206.2806.7607.200

1030mm

1530mm

XL


Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHXL TIMING BELT/PULLEY0.200” PITCH

6.35210

9.52330

12.7390

19.05630

XL Belt Width in mmNewtons




MAX. BELT CAPACITYMax. power 5kwMax. speed 40,000 RPMMax. recommended belt speed 80m/s

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M spezNcmcm

P spezWcm

Rpmn

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FU spezN

cm

M spezNcmcm

P spezWcm

Rpmn

min -1

L L

020406080

100200300400500600700800900

10001100120013001400150016001700180019002000

37.4036.3035.3034.5033.8033.1030.7028.9027.5026.4025.5024.7024.0023.3022.7022.2021.7021.3020.8020.4020.1019.7219.3919.0818.78

5.6705.5005.3505.2305.1205.0204.6504.3804.1804.0103.8603.7403.6303.5303.4503.3703.2903.2203.1603.1003.0402.9902.9402.8902.850

0.0000.1150.2240.3290.4290.5260.9741.3771.7492.1002.4302.7403.0403.3303.6103.8804.1404.3904.6304.8705.1005.3205.5405.7505.960

2200240026002800300032003400360038004000450050005500600065007000750080009000

10000

18.2217.7117.2516.8116.4016.0215.6615.3215.0014.6913.9913.3612.7912.2711.7911.3410.3610.549.839.19

2.7602.6902.6102.5502.4902.4302.3702.3202.2702.2302.1202.0301.9391.8601.7871.7191.6561.5971.4901.393

6.3708.7507.1207.4707.8108.1408.4508.7609.0509.3309.990

10.61011.17011.69012.16012.60013.01013.38014.04014.590

1560mm

2060mm

L


Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHL TIMING BELT/PULLEY3/8” PITCH

13840

191260

251680

382520

L Belt Width in mmNewtons





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FU spezN

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M spezNcmcm

P spezWcm

Rpmn

min -1

H H

020406080

100200300400500600700800900

10001100120013001400150016001700180019002000

44.0042.7041.6040.7039.8039.1036.1034.1032.5031.5030.0029.1028.2027.5026.8026.2025.6025.1024.6024.1023.7023.2022.9022.5022.10

8.9008.6408.4108.2208.0507.8907.3006.8906.5606.3006.0705.8805.7105.5505.4105.2905.1705.0604.9604.8704.7804.7004.6204.5404.470

0.0000.1810.3520.5160.6740.8271.5302.1602.7503.3003.8104.3104.7805.2305.6706.0906.5006.8907.2807.6508.0108.3608.7109.0409.370

2200240026002800300032003400360038004000450050005500600065007000750080009000

10000

21.5020.9020.3019.8119.3318.8818.4518.0517.6817.3216.4915.7415.0714.4613.8913.3612.8712.4211.5810.83

4.3404.2204.1104.0003.9103.8203.7303.6503.5703.5003.3303.1803.0502.9202.8102.7002.6002.5102.3402.190

10.00010.60011.18011.74012.27012.79013.28013.76014.22014.66015.70016.66017.55018.36019.11019.80020.40021.00022.10022.900

1460mm

2080mm

H


Type of Teeth


with contraflexure

TOOTH SHEAR STRENGTHH TIMING BELT/PULLEY1/2” PITCH

191600

252000

383200

514200

H Belt Width in mmNewtons





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HTD TIMING BELTS SYMBOL DESCRIPTIONS

yxdpk

anom

dpg

a = Drive centre distance (mm)

anom = Drive centre distance with standard belt length (mm)

bst = Standard belt width

C0 = Basic service factor

C1 = Tooth in mesh factor

C2 = Overall service factor

C3 = Speed ratio correction factor

C6 = Fatigue correction factor

C7 = Length factor

da = Outside diameter of pulley (mm)

dp = Pitch diameter of pulley (mm)

dpg = Pitch diameter of large pulley (mm)

dpk = Pitch diameter of small pulley (mm)

dp1 = Pitch diameter of driving pulley (mm)

dp2 = Pitch diameter of driven pulley (mm)

Ea = Belt deflection for given span length(mm)

f = Test force (N)

i = Speed ratio

L = Drive span length (mm)

LpSt = Standard pitch length of timing belt (mm)

Lpth = Calculated pitch length of timing belt(mm)

nk = Speed of small pulley (min-1)

n1 = Speed of driving pulley (min-1)

n2 = Speed of driven pulley (min-1)

P = Power to be transmitted by timing beltdrive (kW)

PB = Design power (kW)

PN = Rated power (kW)

PU = Transmissible power for standard beltwidth (PN x C1 x CZ) (kW)

Sa = Minimum static shaft loading whenstationary (N)

Snperm = Maximum permissible peripheral force(N)

Sn3 = Peripheral force to be effectivelytransmitted (N)

Sn = Peripheral force to be effectivelytransmitted including actual centrifugalforce (N)

SZ = Peripheral force referred to 25mm beltwidth (N)

SZB = Actual peripheral force (N)

t = Tooth pitch (mm)

v = Belt speed (m/s)

x = Minimum adjustment of drive centredistance enom for tensioning timing belt(mm)

y = Minimum adjustment of drive centredistance enom for installation (mm)

Ze = Number of teeth in mesh of small pulley

Zg = Number of teeth on large pulley

Zk = Number of teeth on small pulley

Zr = Number of teeth on timing belt

Z1 = Number of teeth on driving pulley

Z2 = Number of teeth on driven pulley

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HTD TIMING BELTSDESIGN CALCULATIONSThe basic service factor c0 takes account of the daily operating time and the types of prime mover anddriven unit. As it is practically impossible to summarise every conceivable combination of primemover/driver unit/ambient conditions, the service factors represent guide values. In special cases, suchas increased starting torque values, drive systems with high stop/start frequencies, or with fastaccelerations or decelerations, the service factor should be increased. The overall service factor C2 isdetermined by addition of the values found in tables 1, 2 and 5. NOTE:- WHERE 6 TEETH OR MORE ARE

IN MESH WITH THE SMALL PULLEY THEIR SHEAR STRENGTH EXCEEDS THE TENSION STRENGTH OF THE

TENSION CORD.

Service conditions and examples of prime movers

Steady operation

Electric motorsHigh-speed turbines

Piston engines with largenumber of cylinders

Service factor C0 at number ofoperating hours per dayType of service and examples ofmachine applications up to 16 h over 16 h up to 16 h over 16 h

Lightweight drives, shock-free andsteady runningMeasuring equipment, film cameras, officemachinery, belt conveyor systems (lightweightgoods).

1.3 1.4 1.4 1.5

Medium drives, intermittent operationwith low to medium shock loadingMixing machines, kitchen machines, printingmachines, textile machines, packagingmachines, belt conveyor systems (heavygoods).

1.6 1.7 1.8 1.9

Heavy duty drives, intermittentoperation with medium to high shockloadingMachine tools, woodworking machines,eccentric drives, conveyor systems (heavygoods).

1.8 1.9 2.0 2.1

Very heavy duty drives, continuousoperation with high stock loadingGrinding mills, calenders, extruders, pistonpumps and compressors, lifting gear.

2.0 2.1 2.2 2.3

Intermittent operation

Hydraulic motorsLow-speed turbines

Piston engines with smallnumber of cylinders

C0Table 1

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HTD TIMING BELTSBELT SELECTION GRAPH

Design Power PB = P x c2 (kW)

Graph 11400010000

8000

6000

4000

2000

1000

800

600

200

400

100

80

60

40

20

100,1 0,2 0,4 0,6 1 2 3 4 6 8 10 20 40 60 100 200 400 700 1000

Spee

d of

Sm

all P

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y (m

in-1)

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Table 2Length Factor c7

HTD TIMING BELTSDRIVE DESIGN - ADDITIONAL FACTORS

TYPE 3MPitch Length (mm) C7

& 190 0.8> 190 & 260 0.9> 260 & 400 1.0> 400 & 600 1.1> 600 1.2

Table 3 : Teeth in Mesh Factor c1Number of Teeth in Mesh Ze

6 and more5432

Table 4 : Fatigue Correction Factor c6Operating Conditions

Continuous 24-hour operationand/or use of a tensioning idler

Table 5 : Speed Ratio Correction Factor c3

Speed Ratio i

1.00 - 0.800.79 - 0.570.56 - 0.400.39 - 0.280.27 and smaller

Speed Ratio Correction Factor C3

0.000.100.200.300.40

Correction Factor C6

0.20 per idler

For unusual operatingconditions, the followingshould be added to the basicservice factor C0

The factors and corrections inTables, 3, 4 and 5 apply to allHTD types.

For speed increasing drives,the factor corresponding tothe speed ratio should beadded to the basic servicefactor C0

Further corrections to the overall service factor may become necessary in the caseor reversing drives, brake motors, electric brakes, etc.

Teeth in Mesh Factor C1

1.000.800.600.400.20


& 1190 0.80> 1190 & 1610 0.90> 1610 & 1890 0.95> 1890 & 2450 1.00> 2450 & 3150 1.05> 3150 1.10


& 3000 0.90> 3000 & 3400 0.95> 3400 & 4600 1.00> 4600 & 5400 1.05> 5400 & 1.10


& 440 0.8> 440 & 555 0.9> 555 & 800 1.0> 800 & 1100 1.1> 1100 1.2


& 600 0.8> 600 & 880 0.9> 880 & 1200 1.0> 1200 & 1760 1.1> 1760 1.2

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Recommended Drive Centre Distance

0.5 (dpg + dpk) + 15 < a < 2 x (dpg + dpk)Theoretical and standard pitch length Lpth, LpSt

" (dpg — dpk)2Lpth = 2 a + x (dpg + dpk) +

2 4 a

LpSt Standard belt length, see pages for HTD Belts.

Nominal Drive Centre Distance anom

(dpg — dpk)2anom = K + K2 —

8

Lpst " K = — (dpg + dpk)

4 8

Drive centre distance anom to be provided withadjustments for installation y1 and tensioning x1

x1 ' x + 0.002 x anom x from Table 6y1 depending on flange arrangement, minimum adjustment y

y1 ' y y from Table 6

Calculation and setting of tension, see relevant page.

Length Factorc7 from Table 2

Number of Teeth in Mesh on a Small Pulley

zk dpg — dpk ze = (3 — )6 anom

HTD TIMING BELTSCALCULATION FORMULAE

Overall service factorc2 = c0 + c3 + c6c0 from Table 1c3 from Table 5c6 from Table 4

Design PowerPB = P x c2

Selection of Timing Belt TypeSee graph 1

Speed Ratio

n1 z2 dp2i = = = n2 z1 dp1

Number of Teeth on Pulleys

z1z2 = z1 x i

Selected from standard HTDpulley range.

Checking the Speed on theDriven Unit

z2i = z1

n1n2 = i

Teeth in Mesh Factorc1 from Table 3

Belt Width as a function ofrated powerRequirement: PB % PUPU = PN x C1 x C7Required PN value

See relevant belt pages.

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LEaEa

f

&a

L–2

Sa

' 91.44' 254

' 255' 381

' 382' 508

' 509' 762

' 763' 1016

' 1017' 1270

' 1270' 1524

' 1525' 1778LpSt (mm)

± 0.20 ± 0.23 ± 0.25 ± 0.30 ± 0.33 ± 0.38 ± 0.41 ± 0.43Min. drive centredistance adjustment x/y (mm)

HTD TIMING BELTSCALCULATION TENSIONING/MIN ADJUSTMENT X/Y

Table 6 For each additional 254mm length, 0.03mm should be added.

1. Calculation of test force f

Sn3f = 20

P x 1000Sn3 = v

2. Calculation of belt deflection Ea for existing span length L

LEa = 50

dpg – dpk 2

L = a2nom — ( )

2

3. Calculation of minimum static shaft loading

Sa ' Sn3 x 1.1

Minimum adjustment x/y of drive centre distance for correction of length tolerance.When establishing the drive centre distance, provision should be made for adjustment in accordancewith Table 6.

Correct belt tension is of enormous importance for the satisfactory transmission of power and achievement ofnormal belt service life. Frequently, insufficient of excessive tensioning will lead to the premature failure of timingbelts. Over tensioning frequently results in bearing failure on the prime mover or the driven unit. It has been foundthat unscientific tensioning methods, for example the ‘thumb pressure method’ are not suitable for applying theoptimum tension to drive systems for maximum efficiency. It is recommended therefore that the necessary statictension should be calculated for each drive system, using the following formulae. By virtue of their extremely lowstretch properties, it is not necessary with our HTD timing belts to carry out any retensioning after installation.

Formula symbols:f = test force (N)Sn3 = peripheral force to be effectively transmitted (N)Ea = belt deflection for given span length (mm)L = drive span length (mm)

dp1 x n1v = 19100

v m/s

Belt Speed

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HTD TIMING BELTSRATED POWER PN 3mm PITCH, 6mm Wide Belt

Number of Teeth in Pulley

RATED POWER (WATTS)

9.55 11.46 13.37 15.28 17.19 19.10 22.92 26.74 30.56 38.20 45.84 53.48 61.12 68.76 76.39

12248111316182023252627313536394246536066737994108121134159182204

1235101316192225283032333843444752566573818896114131147163192220245

123611161923273033363839455152566267778696105113134154173191226257286

13471318232731353942444652596165727789100111121131155178200221259295327

235815212631354044485052606869758289102114126138150177202227250293332366

2359172430354045505557596876788492100115129142155168198227254279326368404

2471122303744505662687173849497104114123141158175191206243277309339393438476

3581327364553606875828588101113116125136148169189209227246288327364398457505541

3610163243536271808896100104119133137147160173197221243265285334378419456519566596

4913214358718395106117127132137156175179192209226257287315342368427481528569631666670

6111728557490106120134148160167173197219225241261281319355389421451521581631673724729683

71320336687107125142159174189197204232258264283307331375416455492526603667718754781739616

815233875100122143163181199216225233265295302323351377427474517558596678743790816804691

817254284112138161183204224243253262298331339363394423479530578622663749812850861792

919284794128153179203227249270281291330367377403437469530586638685727814871896885739

10 12 14 16 18 20 24 28 32 40 48 56 64 72 80

204060

100200300400500600700800900950

1000120014001450160018002000240028503200360040005000600070008000

100001200014000

Pitch Ø (mm)

Spee

d of

Sm

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PM

When using these pulleys/speeds reduced service life must be expected

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RATED POWER (WATTS)

9.55 11.46 13.37 15.28 17.19 19.10 22.92 26.74 30.56 38.20 45.84 53.48 61.12 68.76 76.39

1336131821262932374042445057596368758698108119129154177198219260298334

134816212631364045495254627072778591106119132144157186214241267314360401

13491826313744495459626373838591101109126141157172185219252283313370421469

14611212937445057636872758596100106118126145163182198214254291327362424482536

348132434425057657278818598111113122134145167186206226245290331372406480544600

3481427394957657381909396111124127137150163188211232254275324372416457534603662

361118364960728191101111116119137154159170186201231259286313337398454506555644718780

4813214459738698111122134139144165185190204223243277309342372401472536596652749828887

491626527086101116131144157163170195218224241262283323362398434467547619687747851928977

61421347095116136155173191208216224255286293314342370421470516560603700788865933103410921098

91827459012114717319621924226227328332335936739542846052358263769073985495210341103118711951120

11213254108142175204232260285309323334380423432464503542614682746806862988109311771236128012111010

13243762122163200234267296326354368382434483495529575618700777847915977111112181295133813181133

132740681371832262643003343673984144294885425555956466937858699471020108712281331139314111298

1431457715420425029333237240844246047754160361866071676986996110461123119213341428146914511211

10 12 14 16 18 20 24 28 32 40 48 56 64 72 80

204060

100200300400500600700800900950

1000120014001450160018002000240028503200360040005000600070008000

100001200014000

Pitch Ø (mm)

Spee

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RATED POWER (WATTS)

22.28 25.46 28.65 31.83 38.20 44.56 50.93 57.30 63.66 70.06 76.39 89.13 101.86 114.59 127.32

491322456176911041171301421481541771992052212422623013383744094435235986697358549561039

511162653729010612213715216617318020723223925728130535039343447451360569076984397210781158

61218306183103122140158174191199206237266274295322349400449496541585688783870950108811931264

714213569941171391591791982162252342683013093333643944515065596096587728779711057119912991354

918264488119147174199223247269280291334375384414451488558625688749808943106411711264140314761473

112132541071451792112412712993263393524034514634985435866697488228939611115125013651459157715941495

13263864128172213251286321353385401416475532545586638688784874960104011161288143315501637171416431403

153045751502022492923343734114474654835516156316777367949021004110011901274145916101722179418041609

173552871742332863363834284715125325526297027207718389021024113712421340143116281778188019271842

20406010019926632638243548553358060362571079181186994310141148127213861492158917921937201920311819

234568113226300368430489545598650675699794884905969105011281274140815311644174519512084213721011729

27548013426835643651058064670976979982893910441070114412391329149716491786190820152212230122682100

31619215330640749858666273980987991294510721191122013031410151116971863200821342238240224112245

3469103172345458561656745829910987102510621204133613681461157816891891206722172340243625412434

387711519238350962372882792110101096113711781334148015151617174518642079226224112526260426232358

14 16 18 20 24 28 32 36 40 44 48 56 64 72 80

204060

100200300400500600700800900950

1000120014001450160018002000240028503200360040005000600070008000

100001200014000

Pitch Ø (mm)

Spee

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RATED POWER (WATTS)

22.28 25.46 28.65 31.83 38.20 44.56 50.93 57.30 63.66 70.06 76.39 89.13 101.86 114.59 127.32

14 16 18 20 24 28 32 36 40 44 48 56 64 72 80

204060

100200300400500600700800900950

1000120014001450160018002000240028503200360040005000600070008000

100001200014000

Pitch Ø (mm)

Spee

d of

Sm

allP

ulle

y R

PM

716244183113141169199218242264276287330371382412451488561630697762826975111512471370159217821937

9202948681341671972272552833093223353864324454795245686527328098839561128128614341572181220102159

11223355113154192227261294324356371384441496510550600650745837924100810901283146016221771202922242357

132639651281752182592963333694024194364995615766216787348419431042113512271439163518101971223624222525

16334882164221274324371415460501522542622699716772841910104011651283139615061758197421832357261627522746

20395910019927033339344950555760763265675184186392810121092124713941532166517922079233125452720294029722788

2448701192383203974685335986587177477758859921016109211891283146216291790193920812401267228903052319630642616

27558313927937646454462269576683386790010271146117612621372148016821872205122192375272030023211334533643000

31659616232443453362671479887895499210291173130913421437156216821909212023162498266830363315350635933435

37741111863714966077128119049931081112411651324147515121620175818912140237225842782296333413612376537873392

4283126210421559686801911101611151212125813031480164816871807195821032375262528553065325436383886398539183221

50100148249499663813951108112041322143414901544175119461995213323102478279130753330355837574125429142293916

57113171285570759928108712341376150816391700176219992221227524292629281731643474374439794173447944964186

63128192320643854104612231389154616971840191119802245249125512724294231493526385441344363454247384539

70143214358714949116113571542171718832043212021962487276028253015325434763877421844964710485648914397


TIMIN

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RATED POWER (kW)

56.02 61.12 66.21 71.30 76.39 81.49 86.58 91.67 96.77 101.86 112.05 122.23 132.42 142.60 162.97 183.35 203.72

0.020.030.080.160.330.490.650.810.981.141.301.551.631.952.352.592.923.233.554.024.574.805.576.327.047.758.439.09

0.020.040.090.180.370.530.710.891.071.241.421.691.772.132.572.833.183.523.874.384.975.226.056.857.628.379.099.77

0.020.040.110.220.450.650.841.021.211.381.561.831.932.312.793.073.453.824.194.755.385.656.547.398.229.009.7510.46

0.030.050.130.270.530.770.991.221.431.641.852.162.262.653.133.423.784.184.595.195.886.177.138.058.939.7610.5511.28

0.030.060.160.310.620.901.161.421.671.922.172.522.643.103.663.994.424.845.255.846.516.797.728.719.6410.5211.3412.09

0.040.070.180.360.721.041.341.641.932.222.502.913.053.584.234.615.105.586.056.747.517.828.849.7810.6411.4112.1212.89

0.040.080.210.410.821.191.541.882.212.542.863.333.484.094.835.265.826.376.917.698.568.9210.0711.1312.0912.9613.7214.36

0.050.090.230.470.931.341.742.132.512.883.243.773.954.635.475.966.597.217.828.698.6710.0811.3712.5513.6214.5815.4116.10

0.050.100.260.521.051.511.962.392.823.233.644.244.445.216.146.697.408.098.779.7510.8511.3012.7314.0415.2316.2717.1717.91

0.060.110.280.561.131.642.122.593.053.503.944.584.805.636.647.237.998.749.4710.5211.6912.1813.7015.0916.3217.4018.3119.04

0.060.120.310.621.241.782.312.823.323.814.284.995.226.127.217.848.679.4710.2411.3612.6013.1114.6816.0917.3018.3119.1019.65

0.070.130.330.671.341.932.503.053.594.114.635.385.636.607.778.449.3210.1711.0012.1813.4713.9915.6016.9918.1419.0419.6419.96

0.070.140.360.721.442.072.683.273.854.414.975.776.047.078.319.039.9610.8611.7312.9514.2914.8216.4417.7918.8419.5719.95

0.080.150.380.771.542.222.873.504.114.715.306.166.447.548.859.6110.5911.5312.4313.7015.0615.6017.2018.4719.3819.89

0.090.170.430.871.732.503.233.944.635.305.966.917.238.449.8910.7311.7912.8013.7615.0916.4616.9918.4719.4819.96

0.100.190.480.961.932.773.594.375.135.876.607.657.999.3210.9011.7912.9213.9914.9816.3217.6518.1419.3819.96

0.110.210.531.062.123.053.944.805.636.447.238.378.7410.1711.8512.8013.9915.0916.0917.4018.6219.0419.89

22 24 26 28 30 32 34 36 38 40 44 48 52 56 64 72 80

102050

100200300400500600700800950

1000120014501600180020002200250028503000350040004500500055006000

Pitch Ø (mm)

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RATED POWER (kW)

56.02 61.12 66.21 71.30 76.39 81.49 86.58 91.67 96.77 101.86 112.05 122.23 132.42 142.60 162.97 183.35 203.72

0.030.050.130.260.510.771.031.281.541.802.052.442.573.083.714.094.605.105.606.357.217.588.799.9811.1312.2513.3414.39

0.030.060.150.290.580.841.121.401.681.962.242.662.803.354.054.465.015.566.106.917.858.249.5510.8212.0513.2414.3915.48

0.040.070.180.350.701.021.321.611.902.182.462.893.043.644.394.845.446.036.627.498.508.9310.3311.6812.9914.2515.4516.58

0.040.080.210.420.841.211.571.922.262.592.923.403.564.194.945.395.976.607.248.199.289.7511.2612.7214.1215.4616.7217.90

0.050.100.240.490.981.411.832.242.643.033.413.984.164.895.786.306.977.648.289.2310.2910.7312.2113.7715.2616.6717.9919.20

0.060.110.280.571.131.632.122.593.053.503.944.604.815.656.677.278.058.819.5510.6411.8612.3613.9715.4716.8518.0919.2420.49

0.060.130.320.651.291.872.422.963.494.004.515.255.506.467.628.309.1910.0610.9112.1413.5214.0915.9217.6119.1520.5521.7822.84

0.070.150.370.731.472.122.753.363.954.545.115.956.237.318.639.4010.4011.3812.3413.7315.2815.9317.9719.8621.5823.1224.4725.62

0.080.170.410.831.652.383.093.774.445.105.746.697.008.219.6910.5511.6812.7813.8515.4017.1417.8620.1322.2324.1325.8227.2828.51

0.090.180.440.891.782.583.344.084.815.526.217.737.578.8810.4711.4012.6113.8014.9516.6118.4719.2421.6723.8825.8827.6329.1230.34

0.100.190.490.971.952.813.644.455.236.006.767.868.239.6511.3712.3713.6814.9516.1817.9519.9220.7223.2425.5027.4629.1230.4431.41

0.110.210.531.052.113.043.944.815.666.497.308.498.8810.4112.2513.3314.7216.0717.3719.2421.2922.1324.7126.9628.8430.3431.4132.03

0.110.230.571.132.273.274.235.166.076.967.839.119.5211.1613.1214.2615.7317.1618.5320.4822.6023.4626.0628.2630.0031.2632.00

0.120.240.611.212.423.494.525.526.497.438.369.7110.1611.8913.9715.1716.7218.2119.6421.6723.8424.7127.3029.3930.9331.88

0.140.270.681.372.733.945.096.217.308.369.4010.9111.4013.3315.6216.9418.6320.2421.7623.8826.1026.9629.3931.1032.03

0.150.300.761.523.044.385.666.898.109.2710.4112.0712.6114.7217.2118.6320.4322.1323.7225.8828.0428.8430.9332.03

0.170.330.841.673.344.816.217.578.8810.1611.4013.2113.8016.0718.7320.2422.1323.8825.5027.6329.6430.3431.88

22 24 26 28 30 32 34 36 38 40 44 48 52 56 64 72 80

102050

100200300400500600700800950

1000120014501600180020002200250028503000350040004500500055006000

Pitch Ø (mm)

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RATED POWER (kW)

124.78 129.23 133.69 142.60 151.52 160.43 169.34 178.25 187.17 196.08 204.99 213.90 231.73 249.56 285.21 320.86 356.51

0.20.40.71.11.83.64.96.17.28.29.110.011.311.613.114.615.416.417.318.620.121.523.124.126.829.1

0.20.40.81.21.93.95.36.67.88.99.910.812.112.614.115.716.617.718.619.320.722.123.824.727.529.6

0.20.40.81.32.14.25.77.18.49.510.611.613.113.515.116.917.818.919.820.621.322.724.425.328.030.1

0.20.51.01.52.44.86.68.29.611.012.213.414.915.417.319.220.321.522.523.324.024.425.626.529.130.8

0.30.61.11.72.85.57.59.311.012.513.915.116.917.519.521.722.824.125.226.126.727.222.427.530.831.4

0.30.61.21.93.16.28.510.512.314.015.617.019.019.621.824.225.526.828.028.929.529.930.030.130.731.6

0.30.71.42.03.46.89.211.413.315.116.818.320.421.023.425.927.128.529.730.531.131.431.331.031.231.6

0.40.71.42.23.67.29.712.014.115.917.719.321.422.124.527.128.329.730.831.532.032.131.831.631.531.4

0.40.81.52.33.87.610.312.714.816.818.620.322.523.525.728.329.530.931.932.532.832.732.131.531.730.8

0.40.81.62.44.08.010.813.315.617.719.521.323.624.326.829.430.732.032.933.433.533.232.331.531.6

0.40.81.72.54.28.411.414.016.418.520.522.324.625.428.030.631.833.033.834.234.233.732.431.431.3

0.40.91.82.74.48.912.014.717.219.421.423.225.726.529.131.732.934.034.735.034.733.932.331.630.8

0.51.01.92.94.99.713.116.118.721.123.225.227.728.531.233.834.935.836.236.135.334.031.731.5

0.51.02.13.15.210.514.217.420.222.725.027.029.730.533.235.736.637.337.436.735.433.431.430.8

0.61.22.43.66.012.016.520.123.326.128.630.833.634.437.139.239.839.838.937.034.230.9

0.71.32.74.06.713.518.922.926.429.532.234.537.438.240.742.342.341.339.135.6

0.71.53.04.57.515.021.325.829.632.935.838.241.141.944.144.844.141.838.0

28 29 30 32 34 36 38 40 42 44 46 48 52 56 64 72 80

10204060

100200300400500600700800950

1000120014501600180020002200240026002850300035004000

Pitch Ø (mm)

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RATED POWER (kW)

124.78 129.23 133.69 142.60 151.52 160.43 169.34 178.25 187.17 196.08 204.99 213.90 231.73 249.56 285.21 320.86 356.51

0.30.51.11.62.75.47.39.110.712.213.715.016.817.419.521.923.124.625.927.930.132.334.836.240.644.2

0.30.61.21.72.95.87.99.911.613.214.716.218.118.721.023.524.926.427.829.031.033.235.837.241.645.1

0.30.61.31.93.16.38.610.612.514.315.917.419.520.122.625.226.628.329.730.932.034.136.738.242.545.8

0.40.71.42.23.67.29.912.214.416.418.219.922.323.125.828.830.332.233.735.036.036.838.640.044.247.2

0.40.81.62.54.18.211.213.916.418.620.722.625.326.129.232.434.136.137.839.140.240.941.441.745.748.2

0.50.91.92.84.79.312.715.718.420.923.225.428.429.332.636.238.140.242.043.444.445.145.445.646.948.9

0.51.02.03.05.010.113.716.919.922.525.027.330.431.435.038.740.642.844.545.946.847.147.247.347.949.2

0.51.12.13.25.310.714.517.921.023.826.428.832.033.036.740.542.444.646.247.448.248.548.347.848.649.1

0.61.12.33.45.711.315.318.922.125.127.830.333.634.738.442.344.246.347.948.949.549.648.948.149.148.6

0.61.22.43.66.011.916.219.923.326.429.231.735.236.340.144.045.948.049.450.350.750.549.448.349.2

0.61.32.53.86.312.617.020.924.527.630.633.236.837.941.845.847.649.650.951.651.751.249.648.449.1

0.71.32.64.06.613.217.922.025.628.932.034.738.439.543.547.549.351.252.352.852.651.749.648.948.6

0.71.42.94.37.214.519.524.027.931.534.737.641.542.646.750.652.353.954.754.653.852.149.149.2

0.81.63.14.77.815.721.225.930.233.937.340.444.445.649.853.555.156.356.655.954.251.549.148.6

0.91.83.65.48.917.924.630.034.839.042.746.050.351.555.658.960.060.259.256.853.148.8

1.02.04.06.010.120.128.134.239.444.048.151.656.057.361.263.764.062.960.055.5

1.12.24.56.711.222.331.838.544.249.253.557.261.662.866.367.767.064.159.0

28 29 30 32 34 36 38 40 42 44 46 48 52 56 64 72 80

10204060

100200300400500600700800950

1000120014501600180020002200240026002850300035004000

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Belt Types

Max Speedrpm

TT22..55 40000 10 18 15 ( 15 (

TT55 40000 10 15 30 ( 30 (

AATT55 40000 15 20 25 ( 60 (

TT1100 15000 12 20 60 ( 60 (

AATT1100 15000 15 25 50 ( 120 (

TT2200 6000 15 25 120 ( 120 (

AATT2200 6000 18 25 120 ( 180 (

MMXXLL 40000 10 18 15 ( 15 (

MMPP 40000 10 18 15 ( 15 (

XXLL 40000 10 15 30 ( 30 (

LL 15000 15 20 60 ( 60 (

HH 15000 14 20 60 ( 80 (

BBeellttTTyyppeess

Speed of SmallPulley (rpm)

Min. Pitch Diameter(mm)

Min. Number ofTeeth

Min Diameter ofOutside Idler (mm)

33MM

55MM

88MM

1144MM

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The use of pulleys below the recommended minimums should, if possible,

be avoided as otherwise reduced belt life must be expected.

MINIMUM TIMING HTD BELT PULLEY DIAMETERS

20.0020.0020.0050.0050.0050.00

120.00120.00120.00180.00180.00180.00

201816322822343028363028

19.1017.1915.2850.9344.5635.0186.5876.3971.30

160.43133.69124.78

300015001000 300015001000300015001000300015001000

Minimum Number of TeethNormal use Reverse Bending

MINIMUM TIMING BELTS PULLEY DIAMETERSMinimum Roller Diameter

Normal use Reverse Bending

Belt length (mm) Length Tolerance (mm) Center Distance (mm) Allowance for Take up (mm)

250 Under ± 0.41 ± 0.21 3250 to 380 Under ± 0.46 ± 0.23 5380 to 500 Under ± 0.51 ± 0.26 10500 to 750 Under ± 0.60 ± 0.30 10750 to 1000 Under ± 0.66 ± 0.33 151000 to 1250 Under ± 0.76 ± 0.38 151250 to 1500 Under ± 0.82 ± 0.41 251250 to 1750 Under ± 0.86 ± 0.43 251750 to 2000 Under ± 0.92 ± 0.46 30Over 2000 add 0.05mm for each 250mm increase in belt length.

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Length tolerances of Synchroflex® timing belts and ClassicConditions: z=20, i=1, measuring load as per table (not applicable for double-sided belts)

Belt length mm

from to

Length tolerancemeasured over centre

distance mm

Allowable longitudinaltolerance

mm

320630

100019603500

320630

1000196035004500

± 0.15± 0.18± 0.25± 0.40± 0.50±0.80

0.100.120.150.200.250.30

Belt length Tolerances on Center Distance MXL & Classic

TolerancesCONTI SYNCHROBELT® HTD synchronous drive belts areprecision products.They are manufactured with maximum care and accuracy.The tolerances for length, width and thickness areextremely narrow.

Length Tolerances for Synchronous Drive Belts

! 150> 150- 255> 255- 400> 400- 560> 560- 800> 800-1000> 1000-1270> 1270-1500> 1500-1800> 1800-2000> 2000-2250> 2250

± 0.15± 0.20± 0.23± 0.25± 0.30± 0.33± 0.38± 0.40± 0.43± 0.45± 0.48

The tolerance value increases by afurther 0.05 mm per 500 mmincrease in length.

Pitch length Lwmm

Tolerance of centre distancedeviation mm

BELTLENGTH

(mm)

TOLERANCE ONBELT LENGTH

(mm)

TOLERANCEON CENTREDISTANCE

(mm)91 - 254

255 - 381382 - 508509 - 762763 - 990991 -12191220-15241525-17781779-20322033-22862287-25402541-28432884-30483049-36003601-4956

± 0.40± 0.46± 0.50± 0.60± 0.66± 0.76± 0.80± 0.86± 0.90± 0.97± 1.00± 1.06± 1.10± 1.20± 1.40

± 0.200± 0.230± 0.250± 0.300± 0.330± 0.380± 0.400± 0.430± 0.450± 0.480± 0.500± 0.530± 0.550± 0.600± 0.700

TOLERANCES ON BELT LENGTH RPP(HTD)

Documents

Technical Timing