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 ω (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 = π
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)
27. 17Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
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
π • nω =
3019,1 • 103 • v
n = do
do • nv =
19,1 103
M • nP =
9,55 • 103
Fu • do • n=
19,1 • 106
Fu • v =
103
LB = 2 a + π • do= 2 a + z • t
t 1 (Z2 – Z1) t 2LB ≈ (Z2 + Z1) + 2 a +
2 4 a π[ ]
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
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 18
BELT LIFE: The expected belt life is between 10,000 and 15,000 hours, if installedcorrectly and not overloaded.
Technical Section
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 NM = 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 π 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.
Belt width required in cm = b Drive load capacity (with known belt width cm)
Peripheral force
Torque
Power
Speed-up drives
27. 19Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
TIMING BELT CALCULATIONS Technical Section
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 GRAPH
POWER RATING GRAPH FOR SECTIONSELECTION AND MAX. BELT SPEEDS
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 20
Technical Section
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
27. 21Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHT5 TIMING BELT/PULLEY5mm PITCHTOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITYAllowable tensile load on belt cross section Fzul in N.
MAX. BELT CAPACITYMax. power 5kwMax. speed 40000 RPMMax. recommended belt speed 80m/s
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 22
Technical Section
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
6350
10700
161260
252030
322660
504200
756370
1008610
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHAT5 TIMING BELT/PULLEY5mm PITCHTOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITY Allowable tensile load on belt cross section Fzul in N.
27. 23Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
MAX. BELT CAPACITYMax. power 15kwMax. speed 40000 RPMFlank Play 0.2mmMax. recommended belt speed 80m/s
Technical Section
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
T10 Belt Width in mmNewtons
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHT10 TIMING BELT/PULLEY10mm PITCH
Allowable tensile load on belt cross section Fzul in N.
TOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITY
MAX. BELT CAPACITYMax. power 30kwMax. speed 15000 RPMMax. recommended belt speed 60m/s
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 24
Technical Section
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
AT10 Belt Width in mmNewtons
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHAT10 TIMING BELT/PULLEY10mm PITCH
Allowable tensile load on belt cross section Fzul in N.
TOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITY
27. 25Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
MAX. BELT CAPACITYMax. power 70kwMax. speed 15000 RPMFlank Play 0.4mmMax. recommended belt speed 60m/s
Technical Section
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHT20 TIMING BELT/PULLEY20mm PITCH
TOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITY Allowable tensile load on belt cross section Fzul in N.
MAX. BELT CAPACITYMax. power 100kwMax. speed 6000 RPMMax. recommended belt speed 40m/s
T20 Belt Width in mmNewtons
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 26
Technical Section
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
AT20 Belt Width in mmNewtons
18120mm
25180mm
AT20
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHAT20 TIMING BELT/PULLEY20mm PITCH
TOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITY Allowable tensile load on belt cross section Fzul in N.
27. 27Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
MAX. BELT CAPACITYMax. power 250kwMax. speed 6000 RPMFlank Play 0.8mmMax. recommended belt speed 40m/s
Technical Section
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
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHMP, MXL TIMING BELT/PULLEY0.08” PITCH
439
665
10117
16195
MP, MXL Belt Width in mmNewtons
TOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITYAllowable tensile load on belt cross section Fzul in N.
MAX. BELT CAPACITYMax. power 0.5kwMax. speed 40,000 RPMMax. recommended belt speed 80m/s
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27. 28
Technical Section
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
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHXL TIMING BELT/PULLEY0.200” PITCH
6.35210
9.52330
12.7390
19.05630
XL Belt Width in mmNewtons
TOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITYAllowable tensile load on belt cross section Fzul in N.
MAX. BELT CAPACITYMax. power 5kwMax. speed 40,000 RPMMax. recommended belt speed 80m/s
27. 29Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
FU spezN
cm
M spezNcmcm
P spezWcm
Rpmn
min -1
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
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHL TIMING BELT/PULLEY3/8” PITCH
13840
191260
251680
382520
L Belt Width in mmNewtons
TOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITYAllowable tensile load on belt cross section Fzul in N.
MAX. BELT CAPACITYMax. power 12kwMax. speed 15000 RPMMax. recommended belt speed 60m/s
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27. 30
Technical Section
FU spezN
cm
M spezNcmcm
P spezWcm
Rpmn
min -1
FU spezN
cm
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
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
without contraflexure
with contraflexure
TOOTH SHEAR STRENGTHH TIMING BELT/PULLEY1/2” PITCH
191600
252000
383200
514200
H Belt Width in mmNewtons
TOOTH SHEAR STRENGTH
TENSION MEMBER TENSILE STRENGTH
FLEXIBILITYAllowable tensile load on belt cross section Fzul in N.
MAX. BELT CAPACITYMax. power 30kwMax. speed 15000 RPMMax. recommended belt speed 60m/s
27. 31Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
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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27. 32
Technical Section
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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Technical Section
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
ulle
y (m
in-1)
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27. 34
Technical Section
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
TYPE 14MPitch Length (mm) C7
≤ 1190 0.80> 1190 ≤ 1610 0.90> 1610 ≤ 1890 0.95> 1890 ≤ 2450 1.00> 2450 ≤ 3150 1.05> 3150 1.10
TYPE 20MPitch Length (mm) C7
≤ 3000 0.90> 3000 ≤ 3400 0.95> 3400 ≤ 4600 1.00> 4600 ≤ 5400 1.05> 5400 ≤ 1.10
TYPE 5MPitch Length (mm) C7
≤ 440 0.8> 440 ≤ 555 0.9> 555 ≤ 800 1.0> 800 ≤ 1100 1.1> 1100 1.2
TYPE 8MPitch Length (mm) C7
≤ 600 0.8> 600 ≤ 880 0.9> 880 ≤ 1200 1.0> 1200 ≤ 1760 1.1> 1760 1.2
27. 35Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 36
Technical Section
Recommended Drive Centre Distance
0.5 (dpg + dpk) + 15 < a < 2 x (dpg + dpk)Theoretical and standard pitch length Lpth, LpSt
π (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 π 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.
LEaEa
f
βa
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, where LpSt is Standard Pitch Length of timing belt.
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
27. 37Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
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
12248111316182023252627313536394246536066737994
108121134159182204
1235101316192225283032333843444752566573818896114131147163192220245
123611161923273033363839455152566267778696
105113134154173191226257286
13471318232731353942444652596165727789100111121131155178200221259295327
235815212631354044485052606869758289102114126138150177202227250293332366
2359172430354045505557596876788492100115129142155168198227254279326368404
2471122303744505662687173849497104114123141158175191206243277309339393438476
3581327364553606875828588101113116125136148169189209227246288327364398457505541
3610163243536271808896100104119133137147160173197221243265285334378419456519566596
4913214358718395
106117127132137156175179192209226257287315342368427481528569631666670
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
allP
ulle
y R
PM
When using these pulleys/speeds reduced service life must be expected
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27. 38
Technical Section
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
1336131821262932374042445057596368758698108119129154177198219260298334
134816212631364045495254627072778591106119132144157186214241267314360401
13491826313744495459626373838591101109126141157172185219252283313370421469
14611212937445057636872758596100106118126145163182198214254291327362424482536
348132434425057657278818598111113122134145167186206226245290331372406480544600
3481427394957657381909396
111124127137150163188211232254275324372416457534603662
361118364960728191
101111116119137154159170186201231259286313337398454506555644718780
4813214459738698
111122134139144165185190204223243277309342372401472536596652749828887
491626527086101116131144157163170195218224241262283323362398434467547619687747851928977
61421347095116136155173191208216224255286293314342370421470516560603700788865933
103410921098
918274590121147173196219242262273283323359367395428460523582637690739854952
10341103118711951120
11213254108142175204232260285309323334380423432464503542614682746806862988
109311771236128012111010
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
d of
Sm
allP
ulle
y R
PM
HTD TIMING BELTSRATED POWER PN 3mm PITCH, 9mm Wide Belt
When using these pulleys/speeds reduced service life must be expected
27. 39Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
HTD TIMING BELTSRATED POWER PN 5mm PITCH, 9mm Wide Belt
Number of Teeth in Pulley
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
d of
Sm
allP
ulle
y R
PM
When using these pulleys/speeds reduced service life must be expected
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 40
Technical Section
HTD TIMING BELTSRATED POWER PN 5mm PITCH, 15mm Wide Belt
Number of Teeth in Pulley
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
When using these pulleys/speeds reduced service life must be expected
27. 41Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 42
Technical SectionHTD TIMING BELTSRATED POWER PN 8mm PITCH, 20mm Wide Belt
Number of Teeth in Pulley
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
0.040.070.180.360.721.041.341.641.932.222.502.913.053.584.234.615.105.586.056.747.517.828.849.78
10.6411.4112.1212.89
0.040.080.210.410.821.191.541.882.212.542.863.333.484.094.835.265.826.376.917.698.568.92
10.0711.1312.0912.9613.7214.36
0.050.090.230.470.931.341.742.132.512.883.243.773.954.635.475.966.597.217.828.698.67
10.0811.3712.5513.6214.5815.4116.10
0.050.100.260.521.051.511.962.392.823.233.644.244.445.216.146.697.408.098.779.75
10.8511.3012.7314.0415.2316.2717.1717.91
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
0.070.140.360.721.442.072.683.273.854.414.975.776.047.078.319.039.96
10.8611.7312.9514.2914.8216.4417.7918.8419.5719.95
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)
Spee
d of
Sm
allP
ulle
y R
PM
When using these pulleys/speeds reduced service life must be expected
HTD TIMING BELTSRATED POWER PN 8mm PITCH, 30mm Wide Belt
Number of Teeth in Pulley
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
0.030.060.150.290.580.841.121.401.681.962.242.662.803.354.054.465.015.566.106.917.858.249.55
10.8212.0513.2414.3915.48
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
0.050.100.240.490.981.411.832.242.643.033.413.984.164.895.786.306.977.648.289.23
10.2910.7312.2113.7715.2616.6717.9919.20
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)
Spee
d of
Sm
allP
ulle
y R
PM
When using these pulleys/speeds reduced service life must be expected
27. 43Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
HTD TIMING BELTSRATED POWER PN 14mm PITCH, 40mm Wide Belt
Number of Teeth in Pulley
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)
Spee
d of
Sm
all P
ulle
y R
PM
When using these pulleys/speeds reduced service life must be expected
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 44
Technical Section
HTD TIMING BELTSRATED POWER PN 14mm PITCH, 55mm Wide Belt
Number of Teeth in Pulley
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
Pitch Ø (mm)
Spee
d of
Sm
all P
ulle
y R
PM
When using these pulleys/speeds reduced service life must be expected
27. 45Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
Technical Section
Belt Types
Max Speedrpm
T2.5 40000 10 18 15 ∆ 15 ∆
T5 40000 10 15 30 ∆ 30 ∆
AT5 40000 15 20 25 ∆ 60 ∆
T10 15000 12 20 60 ∆ 60 ∆
AT10 15000 15 25 50 ∆ 120 ∆
T20 6000 15 25 120 ∆ 120 ∆
AT20 6000 18 25 120 ∆ 180 ∆
MXL 40000 10 18 15 ∆ 15 ∆
MP 40000 10 18 15 ∆ 15 ∆
XL 40000 10 15 30 ∆ 30 ∆
L 15000 15 20 60 ∆ 60 ∆
H 15000 14 20 60 ∆ 80 ∆
Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
27. 46
The use of pulleys below the recommended minimums should, if possible,be avoided as otherwise reduced belt life must be expected.
MINIMUM TIMING HTD BELTPULLEY DIAMETERS
Minimum Number of TeethNormal use Reverse Bending
MINIMUM TIMING BELTS PULLEY DIAMETERSMinimum Roller Diameter
Normal use Reverse Bending
Technical Section
BeltTypes
Speed of SmallPulley (rpm)
Min. Pitch Diameter(mm)
Min. Number ofTeeth
Min Diameter ofOutside Idler (mm)
3M
5M
8M
14M
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
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.
27. 47Telephone+44(0)1246268080 Fax +44(0)1246260003Unit 14, Foxwood Ind. Park, Foxwood Rd. Chesterfield, Derbyshire S41 9RN
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)
Technical Section