ITALVIBRAS
95
Choice of the vibration method and rotation speed (and, thus, the vibration
frequency) of the electric vibrator applied to the elastically insulated machi-
ne, depending on the process
The choice of the vibration method and vibration frequency able to achieve the utmost efficiency for each type of process,
depends on the specific weight and granulometry (or piece size) of the material used in the process itself (consult the Table on
page 92).
Regardless of the selected vibration method, the electric vibrators can be mounted on the machine, elastically insulated with
its axis in a horizontal or vertical position or, if necessary, in an intermediate position between the two directrices.
The angle of incidence “i” (measured in degrees) of the line of force in relation to the horizontal plane should be taken into due
consideration when electric vibrators are applied with the “unidirectional” method.
Important
: the line of force for any angle of incidence must pass through center of gravity “G” of the elastically insulated ma-
chine (see figure below).
Determination of the angle of incidence of the line of force depends on the type of process and must be within the indicated
range.
“G”
e
i
V
TEOc
=
V
teo
+ V
i
Fα
α
Flow of material
Trajectory
Thrust
Particle of material
App
Unidirectional method
Theoretic speed of the
product V
teo
in m/h or cm/s
angle of incidence of the line of
force in relation to the horizontal plane
eccentricity (mm)
peak-to-peak (mm) = 2 x
e
Rotational method
Corrected theoretic speed of
the product V
TEOc
in m/h or cm/s
Flow of material
Calculated
according to α
(see table on right)
Processes / Uses
for special separators (e.g.: the milling industry);
for conveying, unloading, feeding, positioning and sorting;
for sifting, grading and separating;
for fluidized beds.
“i”
da 6° a 12°
da 25° a 30°
da 31° a 45°
da 45° a 80°
i
=
e
=
App
=
angle of inclination of machine in relation to horizontal plane
angle of incidence = 90 -α
speed of incidence (cm/s or m/h)
corrective factor to calculate corrected theoretic speed V
TEOC
eccentricity (mm)
α
=
i
=
Vi
=
F
α
=
e
=
corrected theoretic speed to take the
slant of the machine into account
Corrected theoretic of the product
V
TEOc
=
V
TEO
=
Established
value
Values calculated
according in α
α
i
F
α
V
i
10°
80°
0,81
80
15°
75°
0,71
75
20°
70°
0,60
70
25°
65°
0,48
65
35°
55°
0,25
55