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Title / Demonstrate knowledge of semi-worsted and worsted yarn making technology
Level / 5 / Credits / 20
Purpose / This unit standard is for people who require knowledge of the top making process. People credited with this unit standard will be able to demonstrate knowledge of: semi-worsted and worsted fibre blends, semi-worsted and worsted carding, gilling, combing, roving, semi-worsted and worsted spinning mechanisms, and sliver, top and yarn testing.
Classification / Textiles Manufacture > Top Making, Semi-Worsted and Worsted Processing
Available grade / Achieved
Explanatory notes
None.
Outcomes and evidence requirements
Outcome 1
Demonstrate knowledge of semi-worsted and worsted fibre blends.
Evidence requirements
1.1Fibre requirement for semi-worsted and worsted processing is described in terms of fibre properties, processing performance and blend formulation.
Rangefibre properties – fineness, length, strength, cost, handle, lustre;
processing performance – yield, fibre breakage, neps, spinning end breakage.
1.2Blend composition and blending process are described in terms of blend formulation for semi-worsted and worsted processing.
1.3Fibre processing additives that are applied in semi-worsted and worsted processing are described in terms of their function and effect during processing.
Rangeprocessing lubricant, anti-stats, water.
Outcome 2
Demonstrate knowledge of semi-worsted and worsted carding.
Evidence requirements
2.1Carding is described in terms of process objectives.
Rangefibre mixing, fibre disentanglement, fibre parallelisation, maintenance of fibre length, vegetable matter removal, web formation.
2.2Card sections and components are described in terms of function, setting and operation.
Rangefeed section, breast, swift, doffer, coiler, feed control, web monitoring.
2.3Card clothing used in semi-worsted or worsted carding is described in terms of type and reasons for selection.
Rangetype – fillet, metallic;
reasons – card performance, sliver quality.
2.4Fettling process is described in terms of reasons for fettling and methods used.
Rangemethod – hand, vacuum;
reasons – carding performance, product quality, contamination.
2.5Carding actions are described and diagrams used to illustrate relationship between roller direction and speed.
Rangepoint to point, point to back, back to back.
2.6Vegetable matter removal methods are described and compared to demonstrate knowledge of operation and performance.
Rangeburr rollers, Morel rollers, Harmel rollers, twin burr, peralta.
2.7Carded sliver faults are described in terms of cause, significance and corrective action.
Rangeneps, excessive vegetable matter, fibre breakage, short and long term unevenness.
Outcome 3
Demonstrate knowledge of gilling.
Evidence requirements
3.1Gilling process is described in terms of principles and reasons.
Rangepreparer gill, finisher gill, fibre alignment, short fibre control, draft, doubling, sliver package.
3.2Gill box components and sections are described in terms of function and operation.
Rangecreel, front rollers, back rollers, faller bars, faller pins, front ratch, back ratch, autoleveller, coiler, chain gill, intersector gill, rotary gill, porcupine roller.
3.3Gilled sliver faults are described in terms of cause, significance, and corrective action.
Rangeuneven sliver, fibre breakage.
Outcome 4
Demonstrate knowledge of combing and top package formation.
Evidence requirements
4.1Combing process is described in terms of principles and reasons.
RangeFrench or rectilinear comb, noble comb, noils, neps, tare, tare calculation, recombing.
4.2Comb components and sections are described in terms of function and operation, and diagrams produced to show inter-relationship.
Rangefeed gill, shovel plate, nip, intersector comb, draw-off rollers, apron, comb cylinder, noil brush, fillet roller, doffing comb.
4.3Combing actions of French or rectilinear comb are described and diagrams produced to show relationship of machine parts during each action.
Rangeform fringe, comb fringe, draw-off, comb tail, piece sliver together.
4.4Combing faults are described in terms of cause, significance, and corrective action.
Rangeexcessive noil, uneven sliver.
4.5Top package formation methods are described and compared in terms of method and advantages and disadvantages of each method.
Rangeball, bump.
4.6Balled top building mechanism is described in terms of function and operation.
Rangefront roller, calendar roller, traverse motion.
Outcome 5
Demonstrate knowledge of the roving process.
Evidence requirements
5.1Objectives of roving are described in terms of product properties.
Rangereduction of sliver thickness, sliver uniformity, fibre length distribution, fibre alignment.
5.2Principles of roving are described according to industry definitions.
Rangedraft, ratch, fibre control, bobbin lead, flyer lead, twist.
5.3Factors that affect draft are described.
Rangecondition, fibre strength, roving type, fibre control mechanism.
5.4Fibre control mechanisms used in roving are described and compared in terms of function and operation.
Rangepin drafting, roller drafting, apron drafting, porcupine drafting.
5.5Roving systems are described and compared in terms of their function and operation.
Rangecone drawing, rubbing finisher.
Outcome 6
Demonstrate knowledge of the semi-worsted and worsted spinning mechanisms.
Evidence requirements
6.1Fibre control mechanisms used in spinning are described in terms of their function and operation.
Rangedouble apron, Ambler Superdraft, conductors, roller drafting.
6.2Semi-worsted and worsted spinning systems are described and compared in terms of their processing sequence and machine mechanisms.
Rangering spinning, self twist, Siro Spun, Siro Fil, hollow spindle.
Outcome 7
Demonstrate knowledge of sliver, top and yarn testing.
Rangeregain, fatty matter and extractable matter, micron, vegetable content, nep count, fibre diagram, evenness, colour, yarn strength and extension.
Evidence requirements
7.1Tests are described in terms of principles, method and reason for each test.
Replacement information / This unit standard replaced unit standard 3127, unit standard 3128, and unit standard 3137.This unit standard is expiring. Assessment against the standard must take place by the last date for assessment set out below.
Status information and last date for assessment for superseded versions
Process / Version / Date / Last Date for AssessmentRegistration / 1 / 24 November 2005 / 31 December 2019
Rollover / 2 / 21 May 2010 / 31 December 2019
Review / 3 / 19 May 2016 / 31 December 2019
Consent and Moderation Requirements (CMR) reference / 0030
This CMR can be accessed at
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and which are assessing against unit standards must engage with the moderation system that applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies to this standard are outlined in the Consent and Moderation Requirements (CMR). The CMR also includes useful information about special requirements for organisations wishing to develop education and training programmes, such as minimum qualifications for tutors and assessors, and special resource requirements.
CompetenzSSB Code 101571 / New Zealand Qualifications Authority 2018 / / New Zealand Qualifications Aut