Different structures

Wheel tolerances
Belt wheel pitch tolerance
Outer diameter
|
Allowed tolerance
|
Between each tooth
|
90 degree arc tolerance
|
≤25.40
|
0.03
|
0.05
|
25.40~50.80
|
0.03
|
0.08
|
50.80~101.60
|
0.03
|
0.10
|
101.60~117.80
|
0.03
|
0.13
|
117.80~304.80
|
0.03
|
0.15
|
304.80~508.00
|
0.03
|
0.18
|
>508.00
|
0.03
|
0.20
|
Belt wheel outer diameter tolerance
|
|
Belt wheel face run-out tolerance
|
Outer diameter
|
Tolerance
|
Outer diameter
|
Tolerance
|
≤25.40
|
+0.05
|
≤101.61
|
0.10
|
25.40~50.80
|
+0.08
|
101.61~254.00
|
outer dia.×0.001
|
50.80~101.60
|
+0.10
|
>254.00
|
0.25+[(o.d.-254)×0.005]
|
101.60~117.80
|
+0.13
|
Radical run-out tolerance
|
117.80~304.80
|
+0.15
|
≤203.20
|
0.13
|
304.80~508.00
|
+0.18
|
>203.20
|
0.13+[(o.d.-203.2)×0.005]
|
Tooth tolerances
 |
Belt wheel with straight edge tooth size and tolerances |
Code
|
bw
|
hg
|
y+1.5°
|
rb
|
rt
|
2k
|
MXL
|
0.84±0.05
|
0.69
|
20
|
0.35
|
0.13
|
0.508
|
XXL
|
1.14±0.05
|
0.84
|
25
|
0.35
|
0.30
|
0.508
|
XL
|
1.32±0.05
|
1.65
|
20
|
0.41
|
0.64
|
0.508
|
L
|
3.05±0.10
|
2.67
|
20
|
1.19
|
1.17
|
0.762
|
H
|
4.19±0.13
|
3.05
|
20
|
1.60
|
1.6
|
1.372
|
XH
|
7.90±0.15
|
7.14
|
20
|
1.98
|
2.39
|
2.794
|
XXH
|
12.17±0.18
|
10.31
|
20
|
3.96
|
3.18
|
3.048
|
 |
HTD belt wheel size and tolerances |
Code
|
Pitch
|
Tooth height hg
|
Bottom circle radius R
|
Tooth space width S
|
Top circle radius r
|
Angle
|
3M
|
3
|
1.28
|
0.91
|
1.90
|
0.3
|
≈14°
|
5M
|
5
|
2.16
|
1.56
|
3.25
|
0.48
|
≈14°
|
8M
|
8
|
3.54
|
2.57
|
5.35
|
0.8
|
≈14°
|
14M
|
14
|
6.20
|
4.65
|
9.80
|
1.4
|
≈14°
|
 |
Belt wheel with T type tooth size and tolerances |
Code
|
Shape
|
y Grade
|
rt
|
rb
|
2k
|
SE br≤20 teeth
|
N br≤20 teeth
|
SE hg≤20 teeth
|
N hg≤20 teeth min
|
±1.5°
|
max
|
T2.5
|
1.75+0.05
|
1.83+0.05
|
0.75+0.05
|
1
|
25
|
0.2
|
0.3+0.05
|
0.6
|
T5
|
2.96+0.05
|
3.32+0.05
|
1.25+0.05
|
1.95
|
25
|
0.4
|
0.6+0.05
|
0.85
|
T10
|
6.02+0.10
|
6.57+0.10
|
2.6+0.10
|
3.4
|
25
|
0.6
|
0.8+0.10
|
1.85
|
T20
|
11.65+0.15
|
12.6+0.15
|
5.2+0.13
|
6
|
25
|
0.8
|
1.2+0.10
|
2.83
|
 |
STPD/STS belt wheel size and tolerances |
Code
|
Pitch
|
Tooth height hg
|
Bottom circle radius R
|
Tooth space width S
|
2k
|
S2M
|
2
|
0.76
|
1.325
|
1.30
|
0.508
|
S3M
|
3
|
1.11
|
1.975
|
1.95
|
0.762
|
S4.5M
|
4.5
|
1.59
|
2.98
|
2.93
|
0.762
|
S5M
|
5
|
1.89
|
3.275
|
3.25
|
0.96
|
S8M
|
8
|
2.83
|
5.30
|
5.20
|
1.372
|
S14M
|
14
|
4.95
|
9.28
|
9.10
|
2.794
|
 |
Representation gear with trapezium tooth |
 |
Representation of gear with circular arc tooth |
 |
Representation of gear with Germany T shape tooth |