70
F L E X S T E E L
®
Belt Tension Rating
Minimum Recommended Pulley Diameters (Percent of Rated Tension)
PIW
>100% - 125%
75 - 100%
50 - 75%
<50%
Snubs
600 - 1000
36
30
24
16
16
1001 - 2250
48
42
30
24
16
2251 - 3200
60
54
42
36
30
3201 - 3500
72
60
54
42
36
3501 - 4200
78
72
54
42
36
4201 - 4650
84
72
54
48
36
4651 - 6420
90
78
66
54
42
6421 - 6800
96
84
66
54
42
6801 - 8561
120
102
78
60
54
Belt Tension Rating
Minimum Ultimate
Tension
Operating Tension
Cable Diameter
(
nominal)
Cable Pitch
(
Approximate)
Belt Modulus
PIW
PIW
inches
inches
PIW
ST800
4568
685
0.142
0.688
329000
ST1000
5710
856
0.142
0.547
411000
ST1250
7138
1070
0.205
0.855
514000
ST1600
9137
1370
0.205
0.667
658000
ST2000
11421
1712
0.205
0.533
822000
ST2500
14276
2140
0.205
0.428
1027000
ST3150
17988
2697
0.315
0.729
1294000
ST3500
19987
2997
0.315
0.655
1438000
ST4000
22842
3425
0.362
0.753
1644000
ST4500
25697
3853
0.394
0.806
1849000
ST5000
28552
4281
0.433
0.820
2055000
ST5400
30836
4623
0.433
0.764
2219000
ST6000
34263
5137
0.488
0.850
2466000
ST6500
37118
5565
0.488
0.790
2671000
ST7000
39973
5993
0.488
0.738
2877000
ST7500
42828
6421
CONTACT VEYANCE
3082000
ST8000
45683
6849
3288000
ST8500
48539
7277
3493000
ST9000
51394
7705
3699000
ST9500
54249
8133
3904000
ST10000
57104
8561
4109000
Belt Tension Rating
PIW 685
856
1070
1370
1712
2140
2697
2996
Carcass Weight
lb/ft
2
1.4
1.5
2.1
2.3
2.6
2.9
4.2
4.4
Belt Tension Rating
PIW 3424
3852
4280
4623
5137
5565
5993
Carcass Weight
lb/ft
2
5.0
5.5
6.3
6.7
7.5
7.8
8.2
Cover Compound
Stacker
Style BII
ARMA SBR
Compound P
Cover Weight per 1/32" (lb/ft2)
0.18
0.19
0.20
0.19
FLEXSTEEL BELT WEIGHT - Imperial
Approximate belt weight = carcass weight + cover weight. Minimum pulley cover requirements for belts with Sensor Guard® 3/16". Contact VTI Rep for minimum pulley cover that applies to your application. Minimum cover gauge
is dependent on the belt rating.
RECOMMENDED PULLEY DIAMETERS - Imperial
Snubs are defined as having 6" or less belt contact and tension less than 50% of belt rating. Pulley sizes for Flexsteel belts are determined by face pressure on the pulley and/or the pulley-to-cable diameter ratio. All pulleys must be flat
as crowned pulleys will cause excessive center tension in the high modulus steel cable product.
FLEXSTEEL STANDARD SPECIFICATIONS - Imperial
Tension ratings are available in addition to those shown above. Other cable diameters may be substituted according to individual requirements.Operating tensions are based on a 6.67:1 safety factor. Cable pitch based on 48" wide belts.
Minimum transition distance (W = Belt Width) by Idler Angle
Percent of rated tension
20
deg
35
deg
45
deg
More than 90%
2.0
W
3.4
W
4.0
W
60%
to 90%
1.6
W
2.6
W
3.2
W
Less than 60%
1.0
W
1.8
W
2.2
W
recommended minimum transition distance at HALF trough depth
Belt Tension Rating
PIW 600-1000
1001-2250 2251-3200 3201-3500 3501-4200 4201-4650 4651-6420
Cable Diameter
Inches
0.15
0.21
0.32
0.37
0.40
0.44
0.49
FLEXSTEEL BELT THICKNESS - Imperial
Approximate belt thickness = cable diameter + cover guages.