chapter 05 - count variations

1Edalasa/schulungsunterlagen/QUANTUM

USTERUSTER®® QUANTUM CLEARERQUANTUM CLEARER

Count variationsCount variations


USTERUSTER®® QUANTUM CLEARERQUANTUM CLEARERC- & CC - Channel C- & CC - Channel

Cp

Cm

CCp

CCm


Reasons for count variations:

Deviations by mixing in wrong bobbins Peeled-off or uneven rovings can lead to varying

counts within a bobbin Missing of a fiber component



There are two clearing channels for the detection of count variations:

C-Channel monitors yarn count variations only in the start-up phase after the splicing process. Bobbins with wrong counts are detected and the winding position must be stopped with the corresponding alarm functions

CC-Channel monitors the yarn count over the whole winding process



C - Channel:

Important to detect count variations very quickly, before too much yarn is wound on the cone

The choice of the thresholds (Cp, Cm, length) must be adjusted to the conditions of the mill: the produced yarn count of the spinning mill the evenness of the yarn the possibilities of the winding machine regarding the

suction length



CC - Channel:

Long thick/thin places, which are mainly disturbing due to their length, not so much due to their increase/decrease of mass/diameter

Real deviations from the yarn count (several reasons)

Several short, successive events, which are disturbing as a whole in the end product



CC - Channel function: USTERUSTER®® QUANTUM CLEARERQUANTUM CLEARER

0%

+40%

-40%

+20%

-20%

CC-reference length (m)

Yarn mean value abovethe CC-refernce length

CC-channel "window" moves over the yarn signal

0%

+20%

-20%

CCp (%) threshold

CCm (%) threshold

Yarn mean value above the threshold leads to a cut

0%

+40%

-40%

+20%

-20%

CC-reference length (m)

Yarn mean value abovethe CC-refernce length

CC-channel "window" moves over the yarn signal

0%

+20%

-20%

CCp (%) threshold

CCm (%) threshold

Yarn mean value above the threshold leads to a cut


Yarn suction after a CC-cut:

Machines with fault-related yarn suction The winding position gets the information from the yarn clearer, how much yarn has to be removed before the splice is carried out

Machines without fault-related yarn suction The reference length must be adjusted to the machine conditions, i.e. it must be set to less than 2 m in order to remove the yarn pieces with count variation completely



Calculation of yarn count deviations:

Determination of count variation with the clearer installation (ADMV)

Calculation of the count variations with formulas

Determination of count variations with a diagram

Determination of count variations with the USTER® Calculator



Determination of count variation with the clearer installation

The ADMV (Analog Digital Mean Value) presents the 100%-value of the yarn

It can be used for the calculation of deviations between bobbins

The ADMV of other yarn counts, which are likely to be mixed up in the yarn lot, have to be known

The ADMV takes factors like the material or the relative humidity into account



Determination of count variation with the clearer installation

Formula 1:


%100)ADMV(Ayarn

)ADMV(Ayarn)ADMV(ByarnWrong(%)deviationMass


Calculation of the count variations with formulas

Formula 2:


%100)tex(Ayarn

)tex(Ayarn)tex(ByarnWrong(%)deviationMass

Formula 3*:

%100factorA

)factorAyarn(Byarnofvalue(%)deviationMass

* Factors for different yarn materials can be found in the application handbook


Determination of count variations with a diagram


Nm/NecB

-50 -45 -40 -35 -30 -25 -20 -15 -10 -5

130

120

110

100

90

80

70

60

50

40

30

20

10

10 20 30 40 50 60 70 80 90 100 110 120 130 140

+5

+10

+25+20+15

+50+45+40+35+30

1

2

%

%

Nm/NecA


Determination of count variations with the USTER® Calculator


-Diameter -Mass


Determination of count variations with the USTER® Calculator - Example


1. The correct yarn count must be set. Here: Nm 20 (50 tex)

2. The sliding tongue in the middle must be set on the “0” mark


Determination of count variations with the USTER® Calculator - Example


3. If a yarn with the count Nm 18.5 (54 tex) should be detected, the sliding tongue must be set on this count.

4. In the middle, the corresponding deviation can be read on the scale.

chapter 05 - count variations

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