Tamil Nadu HSE First Year Textile Technology flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Tex

Tex is the mass in grams of 1,000 metres of yarn or fibre; it is a direct count system, so a higher tex means a thicker yarn.

Cotton micronaire

Micronaire is an air-flow measure of cotton fineness and maturity, reported in micronaire units; low values indicate finer or immature cotton, high values coarser cotton.

Moisture regain

Moisture regain is the mass of water in a material expressed as a percentage of its oven-dry mass; it is calculated as (wet mass minus dry mass) divided by dry mass times 100.

Reactive dye

A reactive dye contains a reactive group that forms a covalent bond with cellulose in the presence of alkali, giving good wash fastness after unfixed dye is removed.

Silk fibre

Silk is a continuous protein filament produced by the silkworm; fibroin forms the filament core and sericin is the gum that is removed during degumming.

Draft

Draft is the ratio of the surface speed of the front delivery roller to that of the back feed roller in a drafting zone; it reduces sliver or roving linear density.

Carding

Carding opens and cleans fibre tufts, separates fibres and forms a carded sliver; it removes trash, neps and short fibres to improve yarn quality.

Combing noil

Noil is the short-fibre waste removed during combing; a higher noil percentage generally gives a cleaner, stronger yarn but lowers yarn yield.

Twist multiplier

Twist multiplier relates twist per inch to yarn count by TM = TPI divided by the square root of cotton count; it indicates the twist level for a yarn count.

Ring traveller

The ring traveller runs on a ring and inserts twist into the yarn; its mass and speed affect yarn tension, balloon size and end breakage in ring spinning.

Plain weave

Plain weave is the simplest interlacing, with each warp end passing alternately over and under each pick; it gives a firm, flat fabric with a 2×2 repeat.

Wale and course

In knitted fabric, a wale is a vertical column of intermeshed loops and a course is a horizontal row; their counts per centimetre describe stitch density.

Shuttleless loom

A shuttleless loom inserts weft by rapier, projectile, air jet or water jet instead of a shuttle; it generally runs faster and produces less weft waste.

Fabric cover factor

Woven cover factor is calculated as threads per centimetre multiplied by the square root of yarn tex; it estimates how much fabric area is covered by yarn.

Weft knitting

In weft knitting, one yarn runs across the fabric width and forms successive loops in a course; single jersey is a common weft-knitted structure.

Mercerization

Mercerization treats cotton with strong sodium hydroxide under tension, swelling the fibre and improving lustre, strength, dimensional stability and dye uptake; the alkali must be neutralised afterwards.

Singeing

Singeing passes fabric over a flame or hot plate to burn off protruding surface fibres; it gives a smooth surface before dyeing and printing.

Disperse dye

Disperse dyes are finely dispersed, water-insoluble dyes used mainly on polyester and other hydrophobic fibres; they migrate into the fibre under heat and are fixed by thermal treatment.

Screen printing

Screen printing forces print paste through open areas of a mesh screen onto fabric; one screen is used per colour and the paste contains a thickener.

Sanforizing

Sanforizing is a mechanical finishing process that compresses cotton fabric lengthwise to reduce residual shrinkage; the fabric is conditioned and passed through a rubber belt unit.

Coefficient of variation

The coefficient of variation expresses standard deviation as a percentage of the mean: CV% = (standard deviation divided by mean) × 100; it compares variability between samples.

CSP

CSP is count strength product, calculated as yarn count (Ne) multiplied by lea strength in pounds; it is a combined measure of yarn fineness and strength.

AQL

Acceptable quality level is the maximum percentage of defective units considered acceptable in a sampling inspection; it is used with lot size and inspection level to choose a sampling plan.

Martindale test

The Martindale test rubs fabric against a standard abrasive under controlled pressure and measures abrasion resistance or pilling; results are reported in cycles to a defined end point.

Preventive maintenance

Preventive maintenance is planned servicing, inspection, cleaning and lubrication carried out at set intervals to prevent breakdowns and keep textile machinery within specification.

MTBF

Mean time between failures is the average operating time between successive breakdowns of a machine or component; it is calculated from total running time divided by number of failures.

Vibration monitoring

Vibration monitoring measures machine vibration amplitude or frequency to detect unbalance, misalignment, bearing wear or looseness before failure; it is a condition-monitoring technique.

PID controller

A PID controller adjusts a control output using proportional, integral and derivative terms; it reduces steady-state error and improves response in temperature, tension or speed control.

Lockout tagout

Lockout tagout isolates hazardous energy before maintenance by locking the energy-isolating device and attaching a warning tag so the machine cannot be started accidentally.

Cotton dust

Cotton dust is fine airborne dust generated during opening, carding and cleaning; it can cause respiratory disease and must be controlled by local exhaust ventilation and enclosure.

Break-even point

The break-even point is the output at which total revenue equals total cost; it is calculated as fixed cost divided by selling price per unit minus variable cost per unit.

Zero liquid discharge

Zero liquid discharge is an effluent strategy that recovers and reuses water so no liquid waste leaves the site; it usually combines treatment, evaporation and crystallisation.