|
How to calculate film usage
The number of bales that can be wrapped
from a single roll of stretchfilm can be
accurately calculated, provided the following
points are adhered to:
-
THE BALE SIZE ARE OF 1.2m X 1.2m AND
OF UNIFORM SHAPE
-
THE WRAPPER IS CALIBRATED FOR THE
CORRECT NUMBER OF TURNS
4 film layers 24 turns (500mm)
or 16 turns (750mm)
6 film layers 36 turns (500mm)
or 24 turns (750mm)
-
THE FILM IS ACCURATELY AND CORRECTLY
STRETCHED TO 70%
If all the parameters are correct (bale
size, film stretch of 70% and correct number of
bale revolutions) then the following figures
will always be achieved.
Any variation to the above parameters will
cause numbers to differ
Given a standard bale size of 1.2m x 1.2m,
applying film at 70% stretch using the correct
number of turns for the film width used (24
turns for 500mm and 16 turns for 750mm for 4
layers of film) the calculations are as
follows:
|
A
|
BALE CIRCUMFERENCE
( sum length of all four sides of the
bale)
|
|
B
|
TURNS OF THE BALE
|
|
C
|
FILM LENGTH AFTER STRETCH
(film roll length plus 70%)
|
|
Multiply A x B and divide into
C
|
|
FILM WIDTH
|
A
|
B
|
C
|
BALES PER ROLL
|
|
500mm
|
4.8m
(1.2m x 4 sides)
|
24
|
3,060m
(1,800m + 70%)
|
26.5
|
|
750mm
|
4.8m
(1.2m x 4 sides)
|
16
|
2,550m
(1,500m +70%)
|
33.2
|
|