• Determination of trash and dust particles in the Yarn Evenness Tester
• Determination of the diameter, roundness, density and the surface structure of the yarn
• Determination of the yarn hairiness
• Measuring unit for heavy sliver, wool tops in the range 12-80 ktex
• Determination of the unevenness and imperfections (thin and thick places plus neps)
• Determination of foreign matter. Read about Yarn Evenness Tester

High Volume Instrument

• Can test the length, strength, fineness, color and moisture, color characteristics and trash particle content in cotton ,able to determine fineness and maturity properties of fiber
• Determine fiber length and tensile properties
• Automatic Color Tray or increased sampling for higher throughput
• Dual Sampler for increased sampling for higher throughput
• Data acquistion system
• ust include Standard Calibration Materials
• Micronaire Measured by relating airflow resistance  Maturity, Calculated using algorithm
• itl’I
• Length, Upper Halt Mean Length, Uniformity Index, Short Fiber Index Measured optically in a tapered fiber beard which is automatically prepared, Strength and elongation, measured physically by clamping a fiber bundle between 2 pairs of clamps at known distance  Moisture content, using conductive moisture probe  (Color, Rd (Whiteness), +b (Yellowness), color grade, measured optically by different color
• Trash, Particle count. % surface area covered by trash, measured optically by utilizing a digital camera  ;Calculation of spinnability of cotton

Fabric Defect Manual

Introduction

Controlling fabric’s quality in large scale Fabric production facilities has always been a challenging task. Throughout the production process, there are always new and re-occurring defects that can unexpectedly appear on the fabric causing production loss and delays.

It is important to realize, however, that most of the defects can be prevented and/or corrected.

The first and the most important step in taking preventive or remedial actions is to determine the nature and the cause of the problem.

The ability to make this determination quickly and to take the appropriate action is an integral part of any Fabric quality control set-up and can be a great tool for minimizing production loss time and maximizing productivity.

The following is a summarized review of the most common defects/problems associated with each area of fabric production process from yarns to printing.

For each, a brief description, preventive suggestions and corrective measures are offered.

Additional detailed description and related technical information are available if required.

General Descriptions, Guidelines, and Recommendations

Knitting Related Defects/Problems

Torque-

Definition and Causes:

This problem which predominantly occurs with single Jersey fabrics can not easily be seen in the fabric form. However, if the fabric is constructed with an inherent Torque, once sewn in to garments and after the first wash a distortion in the side seams position appears.

This is mainly attributed to yarn twist, and the knitting machine diameter size.

Higher twist levels, finer yarns (36/1, 40/1, 50/1, etc.), and large diameters normally produce more Torque.

Preventive Suggestions:

With lighter weight fabrics, in order to completely eliminate Torque, the use of alternate S and Z twist yarn cones on the knitting machine is recommended.

This, however, is a costly method. The more practical way would be to use yarns with minimum workable twist levels; to use smaller diameter machines and finally to knit the fabric with a cut line.

Corrective Measures:

With fabrics having higher measures of Torque an adjustment in the marker may be the only solution.

Barre Lines-

See yarn Barre in section 1- G

Needle Lines-

Definition and Causes:

The open vertical lines along the Wales lines in a double knit structure is normally caused by the mal-function of the needle’s latch, accumulation of oil-soaked lint and the incorrect alignment of the cam tracks.

Preventive Suggestions:

Regular maintenance and upkeep of the machine elements, and in particular, replacing the needles on a regular basis, are essential.

Corrective Measures:

For this problem, no corrective measures are available.

Sinker Lines-

Definition and Causes:

The open vertical lines along the Wales lines in a single knit structure is normally caused by the miss-timing of the Sinker elements, broken Sinker tips, accumulation of oil-soaked lint and the incorrect alignment of the cam tracks.

Preventive Suggestions:

Regular maintenance and upkeep of all machine elements is essential.

Corrective Measures:

For this problem no corrective measures are available.

Loop and Stitch Length Variations-

Definition and Causes:

Certain plain single knit structures, especially those with looser stitches and at lower tension levels, are more susceptible to stitch length variation. This can be seen on the fabric as a cluster of irregularly shaped loops where loops appear to have different lengths.

This is usually caused by the variation in the bending properties of the yarns.

It could also be due to the variation in the coefficient of friction between the yarns and the elements with which they come into contact with.

Preventive Suggestions:

The use of Yarn Evenness Tester and yarn with sufficient non-silicone lubricants is strongly recommended.

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