Basic HTML Version
The Textile Magazine
DECEMBER 2011
|
117
The mean value re-
flects the grade (how
short are the hairs in
general), the standard
deviation reflects the
quality (the consisten-
cy of the hair length)
of the hairiness.
We define hairi-
ness as the sum of the
mean value and the
standard deviation.
The picture on the
left shows the screen
of the PC where the
signal coming from
the camera is evaluated. The im-
portant values are Hn (mean value)
and Sn (standard deviation). The top
right is the camera picture, below is
a histogram showing the distribu-
tion of the hair lengths. The above
example shows hairs between ap-
prox. 0.15 mm and 1.8 mm length,
the major part of them being approx.
0.3 mm long.
The other picture shows the oper-
ating panel of a singeing unit (our
laboratory machine) consisting of
a centre unwinding device, dedust-
ing unit, singeing machine (for wo-
ven fabrics and knitware), two more
dedusting units and a big batching
device with centre winding. The
hairiness tester is located behind the
dedusting unit following the singer.
The right-hand side shows a preset
hairiness value of 205, the actual
value being 2188.
By means of the company hairi-
ness tester, we are, for the first time,
able to measure and influence the
important variable, i.e., the hairi-
ness, directly. The measured value
is used to control the process param-
eters in more detail. The intensity of
the burners is adjusted depending on
a preselected hairiness value.
The advantages are:
l
It ensures that the
whole batch has the
same hairiness value.
l
In the future simi-
lar articles will be
singed with the same
parameters (repeat-
ability)
l
The gas consump-
tion is only as high
as necessary. If the
desired hairiness is
achieved with a lower
intensity, the settings
are adjusted accord-
ingly.
The improvement that can be
achieved with the use of the hairi-
ness tester is depicted in the follow-
ing images, wherein the fabric has
been perfectly singed with very little
hairiness appearing on the surface.
We have supplied Osthoff senge
hairiness tester to Oswal Hammerle,
Kolhapur, and Ruby Mills, Mumbai.
This underlines the importance of
the online hairiness tester in ensur-
ing perfectly singed fabric quality
online.
w
Osthoff Senge hairiness tester
technology