USTER AFIS PRO - Measurement Principle & Test Results

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Measurement Principle

Test Results

USTER® AFIS PROUSTERUSTER®® AFIS PROAFIS PRO

2Edas/schulungsunterlagen/AFIS

Modules• Nep Classification

• Fiber neps and seed coat neps• Count and size distribution

• Length and Maturity• Length by weight and by number• Short fiber content• Maturity ratio• Immature fiber content

• Trash• Dust• Trash• Total foreign matter

• AutoJet

Measurement Principle: Fiber Individualizer

Measurement Principle: Optical sensors/detectors

• Fiber individualizer separates the cotton sample into three main components:

Lint Trash DustFibers, shortfibers, neps,seed coat

trash, dust, fiber fragments,very large seed coats withlittle or no attached fibers

• The nep module is able to distinguish between neps and seed coat neps

• Each event (fiber, nep, SCN, ) has its own distinct electrical waveform

• Each samples waveform is compared to a standard waveform to determine which classification it most resembles

Voltage U

Nep signal

Fiber signal

Time t

0 50 100 150 200 250 300 350

THRESHOLD VOLTAGE

TIME OF FLIGHT

PEAK VOLTAGE

Measurement PrincipleLength & nep measurement• Optical system• Single fiber measurement• Measured with an opto-electronic sensor• Fiber creates signal/impulse converted to an

electrical signal analyzed and evaluated by computer

Trash & dust measurement• Separate sensor• Same measurement principle as for the length &

nep measurement

Nep Module

Measures: Fiber neps and

seed coat neps

Count and size distribution

Seed Coat Nep

Fiber Nep

Nep Module

• Fiber Neps

entanglements of several fibers

generated under mechanical treatment of the cotton fibers during harvesting, ginning, opening and cleaning in the spinning mill

amount depends on the cotton origin/variety and harvesting method

neps are mainly reduced in carding and combing

amount of reduction depends on the machinery performance and the quality the spinning mill wants to achieve

Nep Module

• Seed Coat Neps

fragments of cottonseed that still have some fibers attached

created mainly in ginning, when the fibers are separated from the seed

amount depends on the quality and the aggressiveness of the ginning process

removal in carding is very difficult, since the attached fibers tend to stick with the process

Nep results

Data Product: Nep Cnt/ g – Nep Count

Nep [m] – Nep Size

SCN Cnt/ g – Seed Coat Nep Count

SCN [m] - Size

Nep Classification Histogram

Distribution of fiber neps (dark)and seed coat neps(shaded) by size (m)

Nep Count per gramSize (m)

Nep Module

> 4131 – 4021 – 3011 – 20

Seed Coat Neps/ gram

Very high> 451High301 – 450

Medium201 – 300Low101 – 200

Very low< 100

DescriptionNeps / gram

• Ranges of Neps and Seed Coat Neps in Raw Cotton (Upland)

Length ModuleMeaning and significance of fiber length: Fiber length is one of the most important

characteristics of cotton Defines the spinnability of the fiber Basis for cotton trading AFIS length measurement targeted towards

process control of spinning mill

USTER® AFIS measurements: Length by weight and by number in [in] or

[mm] Summary table and histograms

Length Module• Difference between by number and by

weight measurement

(n) “by number” (w) “by weight”

4 fibers = 100% 4 fibers = 300 g = 100%

2 short fibers = 50% 2 short fibers = 100g = 33%

Length Module• Difference between by number and by weight

measurement

Europe USA

Johannsen-Zweigle Suter-Webb

2 Systems

by number by weight

"by number" "by weight"

Measured Calculated

Shows the true fiber lengthdistribution in the sample

Biased towards the longerfibers. Longer fibers "weigh"more than shorter fibers

Short and long fibers aretreated equally

Result is looking "better" thanthe "by number" results.

gives more accurateresults for the optimization ofthe processes in spinning

used by mills that are usedto the results of the combsorter array methods such asthe Suter-Webb-Array UQL is close to theclasser’s staple

Length ModuleComparison of the length systems

Length Measurement

Length by weight Length by number

Length Measurement: Data ProductLength distribution by weight:

L (w) Mean length (weight) of the fibers in the sampleL (w) CV [%] Variation of the fiber length around average (weight) [%]SFC (w) [%] Short Fiber Content in [%] of all fibers below 0.50 inches or

12.7 mm (weight)UQL (w) Upper Quartile Length (weight); length of the longer 5% of

all fibers in the sample

Length distribution by number:

L (n) Mean length (number) of the fibers in the sampleL (n) CV [%] Variation of the fiber length around average (number) [%]SFC (n) [%] Short Fiber Content in [%] of all fibers below 0.50 inches or

12.7 mm (number) L (n) 5% The 5% Length (number); length of the longer 5% of all

fibers (number)

Fiber length

Short fiber content SFC (n, w)

L (n,w)UQL(w)

L2,5%(n) L5%(n)

0% 25% 50%

Length Measurement• Graphic representation of the length values in the

staple diagram

Length (w) Report

Distribution of fiberlength (dark) andshort fiber content(shaded) by weight

L(n)[in]

Length (w)

Length (n) Report

Distribution of fiberlength (dark) andshort fiber content(shaded) by number

Length (w)L(n)[in]

Length Module: Short Fiber Content

• Cotton length is determined by variety• first length development, then development of the

walls initially, the fibers have more or less the same

length length is reduced with any mechanical

treatment (harvesting, ginning, opening, cleaning)

• mainly reduced at combing• control of the SFC very important for the spinning

performance and the yarn quality

Length Module

> 1512 – 149 – 116 – 8< 5

Short Fiber Content (weight)

Medium24 – 28Low19 – 23

Very low< 18

DescriptionShort Fiber Content (number)

• Ranges of Short Fiber Content (w) and (n) in Raw Cotton (Upland)

* For long staple cottons, other values apply. The differences are smaller.

Maturity Module

Measures:

• Maturity ratio

• Fineness

• Immature Fiber Content

• Summary table and histograms

Fiber MaturityAfter length development, cellulose is deposited insidethe hollow fiber:

fiber is maturingmaturity = degree of cell wall thickness

= amount of cellulose inside the fiber

Fiber Maturity Calculation of the fiber maturity

Perimeter P

Area A1

Perimeter P

Area A2

To calculate the mean degree of thickening theta, a circular cross-section of the measured fiber having a perimeter P is calculated, and subsequently area A1 is divided by area A2.

ExampleCumulative percent Theta Frequency

Mature fibers (R)

Thinwalled fibers

Immaturefibercontent (IFC)

For this example, the following apply:

Mature fiber content R = 37.6%

Immature fiber content IFC = 10.3%

Maturity (according to Lord):

0.83 0.7200

10.337.6 0.7200

IFC-R M

Fiber Maturity Measurement

• AFIS measures the fiber shape

• Each fiber is measured from two different angles by the optical sensor

• Depending on the shape, cotton fibers are divided into:

• Fully mature - typical convolutions of a mature fiber

• Immature - less obvious convolutions, more flat• Dead - no convolutions, completely flat, “ribbon

like”

Immature Fiber Content

• IFC = Immature Fiber ContentPercent of all fibers within a cotton sample that have a cell wall thickness 25% of the full area

• Effects of immature fibers Dyestuff is deposited in the cellulose immature fibers: no cellulose for the dyestuff to remain

color differences, barré, white specs!

Fiber Maturity MeasurementConvolution of mature cotton fibers

Fiber Maturity MeasurementCross-section of mature cotton fibers

Fiber Maturity MeasurementMature and immature cotton fibers

Fiber Maturity MeasurementImmature cotton fibers

Fiber Maturity MeasurementImmature fiber nep in the fabric (shiny nep)

Fiber Fineness [mtex]

• Determined optically by analyzing the fiber shape passing the sensors

• Algorithm determines fineness based on the shape and form of the fibers and their specific weight

• Mature fibers contain more cellulose heavier

Fiber Maturity

Small perimeter &“fairly mature”

Medium perimeter &“less mature”

Medium perimeter &“fairly mature”

Large perimeter &“well mature”

Maturity Measurement

Data Product:Fine mtex Fineness [millitex]IFC [%] Immature Fiber Content [%]Mat Ratio Maturity Ratio [%]

Maturity Report

Distribution of fibercell wall thickness (dark) and immature fiber content (shaded)

[%]Maturity

Fineness Report

Distribution of fiberfineness (mtex)

[%]Fineness[mtex]

Maturity Module

> 0.950.91 – 0.950.86 – 0.900.76 – 0.85

< 0.75

Maturity Ratio

> 180171 – 180161 – 170151 – 160

Fineness (mtex)

Medium9 – 11Low6 – 8

Very low< 6

DescriptionImmature Fiber Content

• Ranges of Maturity, IFC and Fineness in Raw Cotton (Upland)

Trash ModuleMeasures:• Dust particles smaller than 500 microns• Trash particles larger than 500 microns• Summary table and histograms• Count and size distribution

Trash Module• Definition Trash: “foreign” particles, i.e. not related to any physical properties of cotton fibers.

ITMFDefinition

Particle Size [m]

RespirableDust

MicroDust Dust Trash

15 20 500

Trash Module

Data Product:Total Cnt/ g Count of all particles per gramMean Size Mean size of all particles [m]Dust Cnt/ g Dust particle count per gramTrash Cnt/ g Trash particle count per gramVFM [%] Visible Foreign Matter [% by weight]

Trash Module: Trash Report

Distribution of dust (dark)and trash (shaded)by size (m)

Size[m]

Particle Count per Gram

Trash Module

> 151111 – 15076 – 11026 – 75

< 25Trash Count/ g

> 3.012.31 – 3.001.21 – 2.300.61 – 1.20

< 0.60V.F.M.%

Medium351 – 600Low201 – 350

Very low< 200DescriptionDust Count/ g

• Ranges of Trash, Dust Content and Visible Foreign Matter in Raw Cotton (Upland)

Trash Module• The amount of trash / dust particles in raw

cotton depends highly on:• origin of the cotton• harvesting method• soil conditions

• The amount of trash / dust particles in cotton in the processes in the spinning mill depends highly on:

• the performance of the machinery• suction systems

USTER AFIS PRO - Measurement Principle & Test Results

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