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Step 4. Tension adjustment
Adjust the tension of the belt in such a manner that the read value of the deflection load
matches that shown in the following table.
Table of deflection load
Types of
belts
Range of small
pulley diameter
(mm)
Deflection load P (N/belt)
Minimum value
When a new belt
is stretched
When a belt is
stretched again
M type
38 to 50
4.9
6.9
6.9
A type
65 to 80
81 to 90
91 to 105
106 or more
7.8
8.8
10.8
11.8
11.8
13.7
16.7
17.6
9.8
11.8
13.7
15.7
B type
115 to 135
136 to 160
161 or more
13.7
17.6
18.6
20.6
26.5
28.4
17.6
22.5
24.5
3V type
67 to 90
91 to 115
116 to 150
151 to 300
17.6
19.6
22.5
25.5
24.5
28.4
33.3
38.2
21.6
25.5
29.4
33.3
5V type
180 to 230
231 to 310
311 to 400
57.8
69.6
82.3
85.3
103.9
121.5
74.5
90.2
105.8
(Note) The range of small diameter of 3V/5V type is indicated in nominal diameter.
•
A lack or excess of belt tension causes abnormal phenomena. The following table
indicates how to distinguish a lack of belt tension and an excess of belt tension from each
other.
Abnormal phenomena of belt
Phenomena caused by a lack of tension
Phenomena caused by an excess of tension
•
Slip
•
Heat generation
•
Overturn
•
Vibration
•
Aging of rubber resulting in cracks
•
Wear of side face
•
Reduction of lifetime due to deformation of
the belt on the pulley
•
Heat generation
•
Heat generation of bearing
•
When a belt gets used to the pulley 20 to 30 hours after it enters the field operation phase,
perform a fine adjustment of the belt once again.
•
When using multiple belts stretched, make them matched set for the number of belts to be
used (make the belts the same length).
•
When the tension of the belts has completely been adjusted, make sure to attach the belt
guard to ensure the safety.
Correct
Deformation
