Reasons for Measuring Wool
Generally, it is difficult and expensive to provide customers and clients with raw materials and products that have flawless quality traits. This is because of certain amount of variability inherent in any raw material or product. Wool is an extremely variable product. The heterogeneity of wool is indicated by its attributes that are signifi-cantly different from each other; which makes it difficult to substitute. Wool varies along the fibres, between fibres, between staples, between animals, between flocks, between bloodlines and regions. The wool industry was therefore compelled to improve quality and reduce overall costs in handling, processing and other operations down the woollen and wor-sted pipelines the woollen and wor-sted pipelines.This was approached by controlling and reducing the mentioned inherent quality variability of fibre and on finished textile products. Wool metrologists (metrology engineers & technicians) have pro-vided means and tools to do this. International Wool Textile Organisation (IWTO) sets the testing standards to be followed by the Licensed and Accredited Testing Houses located in Africa (Port Elizabeth), Argentina (Rawson-Chubut), Australia (North Melbourne), Europe (North Wales), New Zealand (Ahuriri Napier) and Uruguay (Montevido). Code of Wool Handling follows the brought principles of IWTO and they are interpreted by authority figures in the industry or marketing organisations in order to endorse classing and grading regulations that help to;
Designate names and standards to different grades
Discourage deceptive presentation of the fibre
Facilitate satisfactory legal marketing transactions
Ensure an accurate price in the market
Facilitate marketing communication
This does not exist for bast and synthetic fibres, producers and individuals have their own estimates of standards and convenience; samples are submitted to the buyers.
Advancement of Objective Measurement (OM)
Since1970 the world (the wool industry) has moved away from subjective appraisal of raw (greasy) wool characteristics and entered into an era of objective measurement and specifications. Ever since the raw wool trade is rapidly moving towards sale by total description which necessitates the accurate rapid and cost effective measurement of all the greasy wool traits important in determining market price, textile performance and end-use. The development and availability of new technologies and equipment have enabled the OM of many more characteristics than was possible. OM on farms has generally involved testing of mid-side samples of wool send to central and subsidiary laboratories. This is for the purpose of measuring the basic traits on fibre diameter, staple length and strength for breeding objectives. In wool handling and grading in the shearing sheds subjective measurement is now used concurrently with the Optical Fibre Diameter Analyser (OFDA). This equipment is used for the quest for on farm objective measurements on wool quality and related properties notably on the mid-side staple(s).
Lesotho and few sheds
In other wool producer countries are not moving towards the OM on farms which has advanced significantly to a large extent. This is due to lack of financing this important process and heavy reliance on the market subsidiaries. In the past two decades the on-farm measurement has increased attention and various instruments have been developed. These among others are the WoolView 20/20, Sirolan-FleeceScan and FibreLux. The wool tests of these equipment are not intended for certification purposes of wool consignments to be sold. It is however projected that with advancement in technology farmers will accurately measure and verify important properties of wool in each bale on farms for the purpose of enhancing wool grading and winning confidence of brokers and clients. Which developed for measuring wool traits but have never progressed beyond the research laboratories stages are;
The entanglement of scoured wool and slivers
Detection and removal of different types of contaminants
Dark and coloured fibres detection in bales
Detection of skirtings, frelies and oddments
A number of institutions around the world have contributed in advancement of OM. Australia took the lead through its universities, research organisations and wool bodies by conducting research studies, trials and experiments to strengthen the OM to the additional measurements; increased in technology and automatic testers is done to quantify the effects of fibre and processing parameters on processing behaviour and performance on the properties of the top, yarn and the fabric. The OM contributes on improving the processing of wool and its productivity and cost effectiveness of the various processing stages. This advancements and developments lead to identification and better understanding of raw wool characteristics influence on textile processing behaviour and performance, as well as the product quality and end-use performance and ultimate greasy wool price. In order to achieve OM wool handling and preparation activities on farms sheds have to be carried out by qualified and experienced classers. The mentioned personnel appraise each wool trait and group it in similar lines. The classers are obliged to follow Code of Practice for Wool Handling and Clip Preparation. The mentioned code consists of set standards guidelines to ensure consistency to meet needs of processors, maximise returns to the growers and create continuous quality assurance.