link no. 59 customer magazine spun yarn systems - Rieter

22 LINK 59 . 1 /2012
TECHNOLOGY
Processing of Indian Cotton
How can 1 1/16" cotton with a high short fiber content best be processed?
Tests on the Rieter rotor spinning and ring spinning systems provide
indications. The possibilities and the potential of processing 100 %
cotton on a rotor spinning machine are today in the Asian countries still
far from being exhausted.
You can obtain further
details on this test in
the 20-page special
print “Processing
Indian Raw Cotton”
which you can download
in Internet using
the printed code.
http://bit.ly/ItN4Lm
Fig. 1 Areas of application
of the spinning
systems.
[1 0 0 0 0 0 0 tons]
(mm)
(inch)
RANGE OF APPLICATION OF THE SPINNING SYSTEMS FOR 100 % COTTON
5 . 0
4 . 5
4 . 0
3 . 5
3 . 0
2 . 5
2 . 0
1 . 5
1 . 0
0 . 5
0
2 3 . 0-2 5 . 4 2 6 . 1 9 2 6 . 9 9 2 7 . 7 8 2 8 . 5 8 2 9 . 3 7 3 0 . 1 6 3 0 . 9 6 3 1 . 7 5 3 2 . 5 4 3 3 . 3 4 3 4 . 1 3 3 4 . 9 3 3 5 . 7 -4 4 . 4 1
2 9 /3 2 -1 1 1 /3 2 1 1 /1 6 1 3 /3 2 1 1 /8 1 5 /3 2 1 3 /1 6 1 7 /3 2 1 1 /4 1 9 /3 2 1 5 /1 6 1 1 1 /3 2 1 3 /8 1 3 /3 2 -1 3 /4
short
AFIS Autojet; commercial staple; UQL (w) (mm)
In the processing of 100 % cotton with the rotor
spinning system, the appropriate field of application
based on economic and quality aspects lies in a staple
length range from 1" to 1 1/8" cotton. According
to the short fiber percentage and trash content of the
cotton, the rotor technology is often the only option
to produce yarn economically – and simultaneously
in the quality demanded. Depending on the staple
length of the cotton, the areas of application for the
various end spinning processes can thereby be allocated
(Fig. 1).
Up to 2010 already 7.8 million rotor spinning units
worldwide have been installed. In comparison to
the installed ring spindles, this number is small.
As, however, the productivity of a rotor unit compared
to a ring spinning unit is higher by the factor
Ring spinning
Rotor spinning Air-jet spinning
medium long extra long
SPINNING UNITS INSTALLED WORLDWIDE 2010
Total installed spinning units [million]
1 6 0
1 4 0
1 2 0
1 0 0
8 0
6 0
4 0
2 0
0
71
162
Fig. 2 Installed spinning units worldwide.
7,8
1,5
Ring carded Ring combed Rotor Air-Jet
6, this corresponds to a percentage of approx. 30 %
of the yarn production. Worldwide, rotor spinning is
an established technology that fulfils the presently
demanded high requirements for the yarn in downstream
processing (Fig. 2).
The yarn fineness with rotor technology lies in the
range from Ne 3 – 40, whereby the typical and mostly
produced yarn count is Ne 30. Yarns in this count
are primarily used in circular knitting but are also
processed in weaving (Fig. 3).
With rotor spinning, various process stages can be
selected for the processing of the fibers (Fig. 4). The
choice of the process operation with rotor spinning
depends on the yarn count to be produced and the
required yarn quality. With the processing of 100 %
cotton and a yarn count of Ne 30, a process using a
card without drafting module and 1 or 2 subsequent
drafting passages is most practical.
Test structures
To be able to show how the two spinning systems
– ring and rotor – react to an increased percentage
of short fibers, Indian Shankar 6 cotton with a relatively
high short fiber percentage was used and processed
to 8 various yarns. The yarn values of these
8 yarns were subsequently compared, so as to define
the optimal procedure for short staple cotton.