Recycling of polyester textiles

Mechanical and chemical routes for recycling polyester are outlined. To be able to make high-quality goods from recycled polyester, pure-grade waste is needed. Hoechst has developed carpets made entirely of polyester which can be successfully regranulated to be spun into fibres again. A pure-grade anorak has also been developed.

Spinning of microfibre yarns

Problems associated with the spinning of microfibres are outlined. Because of their lower breaking strength and bending rigidity, microfibres should be opened carefully. The ring, rotor and air-jet spinning of microfibres are discussed. Viscose rayon, polyester and acrylic microfibres are examined. The ring and rotor yarns are shown to ha..

Effects of various treatments on cots to reduce roller lappings

Several measures are tested in an attempt to find the best way to reduce roller lapping, which increases waste and reduces productivity. Treatment with sulphur monochloride or with 90％ concentrated sulphuric acid reduces roller lapping greatly but sulphur monochloride treatment is not favoured because of the precautions which need to be ..

On-line control of the ratch setting on a drawframe

A drawframe with an automatically controlled ratch setting was constructed which responded to variations in fibre length. The machine reacted to step changes in fibre length and settled into positions close to those recommended by the machine manufacturer for the particular fibres. An expert-system type of control was used. It involved in..

Design of asymmetrical cam profile for improved performance at flyer spinning

The variation of the transmitted yarn tension within and between the layers and cross-layers of the bobbin build-up is assumed to be one of the important causes for end breakage in the flyer spinning system. Since the existing cam of symmetrical profile produces equal traverse rate to the bobbin rail in both its upward and downward moveme..

An analysis of neps due to ramie processing

the composition and causes of formation of neps during the carding, combing and drafting of ramie fibres are discussed. The relationship between fibre length, fibre diameter and nep count is explored. Ball-like and snowflake-type neps are formed. About 80％ of the neps are formed by short fibres with a length shorter than 4cm. About 75％ ..

Simulation technique for analysing and optimizing the operation of a cotton spinning mill

In an analysis of the production stages in ring spinning the materials flow from bale opening to yarn store is analysed and a flow model is developed. The study is made with a view to reducing the operating costs per kg/yarn. It is shown that the final spinning process, consisting of a roving frame, ringframes and a winder, determines abo..

Production and uses of wrap-spun yarns

The production and properties of wrap-spun knitting yarns are considered. It is shown that these yarns need to have fewer fibres in the cross-section than ring-spun yarns and are more uniform than rotor-spun yarns from similar raw materials. Fabrics knitted from these yarns have a uniform loop structure and a soft handle.

Topical treatment of weathered cottons for better processing. III. Initial pilot plant trials

An evaluation of the treatment of weather-damaged cottons with topical lubricants and softeners at the pilot plant scale has been made. Lubricants were applied to about a 0.5％ add-on to damaged cotton in a blending hopper using an atomizing nozzle assembly. In all cases, treated cotton fibres processed more efficiently through carding, d..

Spinning Russian and Turkmenian cotton with high 'starfish' contnet

The object of this study was to investigate the spinnability of Russian and Turkmenian long-staple cotton with the familiar high content of so-called 'starfish', i.e. fimly intertwined fibre bunches with several ends. Ways were to be found for eliminating these starfish, up to and including the card. As the work reveals, this quite possib..