Adjustable Center Drives
Series 21 Standard V-Belt Drives: 7M

 
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7M - 2.8:1 Speed Ratio
H.P.: 1 1/2 Motor Speed: 1800 RPM
H.P.: 1Motor Speed: 1200 RPM
series 21 dimensional drawing
A
2-19/32
B
2
C
2-3/8
D
7
E
3
L
4-21/32
Std. bore
5/8 | 3/4 | 7/8 | 1 | 1-1/8
keyway
3/16 | 3/16 | 3/16 | 1/4
bore depth
2-1/2 | 3 | 3 | 3
max bore
1-1/8
belt size
B
max. p.d.
6.75
min p.d.
2.5
weight
5.5 lb.
Driven Speeds
Driven
Sheave
Pitch
Diameter
Belt vs Minimum Center Distance
1800 RPM Motor
1200 RPM Motor
B 26
B 31
B 35
B 38
B 46
B 55
B 68
B 80
B 85
B 96
B 105
Max.
Min.
Max.
Min.
1735
619
1156
413
7.0
9.1
11.1
13.1
15.6
17.6
20.1
24.1
27.6
32.6
38.6
42.6
1518
542
1012
361
8.0
8.3
10.3
12.3
14.8
16.8
19.3
23.3
26.9
31.9
37.9
41.9
1350
482
900
321
9.0
9.5
11.5
14.0
16.0
18.5
22.5
26.1
31.1
37.1
41.1
1215
433
810
289
10.0
10.7
13.2
15.2
17.7
21.7
25.2
30.2
36.3
40.3
1104
394
736
262
11.0
9.8
12.3
14.3
16.9
20.9
24.4
29.4
35.4
39.4
1012
361
674
240
12.0
11.4
13.5
16.0
20.0
23.6
28.6
34.6
38.6
810
289
540
192
15.0
13.2
17.4
21.0
26.0
32.1
36.1
675
241
450
160
18.0
14.4
18.1
23.3
29.5
33.5

WARNING: All open belt drives must be adequately guarded for personal safety during operation.