3.6 Alignment
The fan is aligned at the factory before shipping, but should be realigned after installation.
Warning
To carry out this alignment work, the inspection door of the silencer
box must be opened. However, be sure to close the door before
starting the fan.
If you run the fan with the door open, the door may close suddenly or
part of your body may get sucked in the machinery, thus causing
injury.
Caution
Incorrect alignment may damage the equipment, or cause vibrations
and noise. Align the fan correctly.
(1) Place a ruler or a piano wire onto the outer surfaces
of the V-belt pulleys on both the fan and motor sides,
and check and adjust it so that the surfaces of the
pulleys are on a straight line (i.e. the axes of the
pulleys are in parallel to each other).
(2) Since V-belts tend to stretch at the early stages of
its use, ensure to readjust it in several days of use.
Use the slide base of the motor to adjust the tension
of the V-belt.
[Procedure]
- Determine the standard deflection
į
: 0.016
Ɛ
.
(
Ɛ
: Distance between pulleys)
- Then use a tension meter to give the standard deflection (
į
mm) in the middle of the V-belt.
Re-tension the belt (or adjust the tension) so that the deflection load at that time becomes the
corresponding value in the following table.
Ruler or piano wire
Make them parallel
V-belt pulley
Motor
Fan
Note
A too loose V-belt may slip or come off.
A too tight V-belt may reduce the service life of the bearings of the
fan and motor.
Deflection load Td for each V-belt type and small pulley OD
V-belt
type
Range of small
pulley outside
diameter (mm)
Deflection load of new
belt
N/belt (kgf/belt)
Deflection load after
re-tension
N/belt (kgf/belt)
A
65
81
91
106
-
-
-
-
80
90
105
9.8 (1.0)
11.8 (1.2)
13.7 (1.4)
15.7 (1.6)
7.8 (0.8)
8.8 (0.9)
10.8 (1.1)
11.8 (1.2)
B
115
136
161
-
-
-
135
160
17.7 (1.8)
22.6 (2.3)
24.5 (2.5)
13.7 (1.4)
17.7 (1.8)
18.6 (1.9)
C
175
206
256
-
-
-
205
255
35.3 (3.6)
42.2 (4.3)
50.0 (5.1)
27.5 (2.8)
32.4 (3.3)
38.2 (3.9)
3V
67
91
116
151
-
-
-
-
90
115
150
300
21.6 (2.2)
25.5 (2.6)
29.4 (3.0)
33.3 (3.4)
17.7 (1.8)
19.6 (2.0)
22.6 (2.3)
25.5 (2.6)
5V
180
231
311
-
-
-
230
310
400
74.5 (7.6)
90.2 (9.2)
105.9 (10.8)
57.9 (5.9)
69.6 (7.1)
82.4 (8.4)
The values in ( ) are expressed in the traditional unit system and shown for
reference only.
Tension meter
3-5
