Doubling (textiles)

Doubling is a textile term that synonomous with combining. It can be used for various processes in spinning process. During the carding stage, several source of roving are doubled together and drawn, to remove variations in thickness. After spinning, yarn is doubled for many reasons. Yarn may be double to produce warp for weaving, to make cotton for lace, crochet and knitting. It is used for embroidery threads and sewing threads, for example: sewing thread is usually 6-cable thread. Two threads of spun 60s cotton are twisted together, and three of these double threads ate twisted into a cable, of what is now 5s yarn. This is mercerised, gassed and wound onto a bobbin.

Processing of cotton

Cotton manufacturing processes Bale breaker Blowing room Willowing Breaker scutcher Batting Finishing scutcher Lapping Teasing Carding Carding room Sliver lap Combing Drawing Slubbing Intermediate Roving Fine roving Mule spinning Ring spinning Spinning Reeling Doubling Winding Bundling Bleaching Weaving shed Winding Beaming Cabling Warping Gassing Sizing/slashing/dressing Spooling Weaving Cloth Yarn (cheese) Bundle Sewing thread

The carding process

In a wider sense carding can refer to the four processes of willowing, lapping, carding and drawing. During willowing the fibers are loosened, in lapping the dust is removed to create a flat sheet or lap of fibers. Carding combs the tangled lap into a thick rope or sliver of 1/2 inch in diameter, and removes the shorter fibers creating a stronger yarn.

During the carding process the staples are separated and then assembled into a loose strand (sliver or tow). The carders line up the staples to prepare them for spinning. The carding machine consists mainly of one big roller with smaller ones surrounding it. All of the rollers are covered in small teeth, and as the cotton progresses further on the teeth get finer (i.e. closer together). The cotton leaves the carding machine in the form of a sliver; a large rope of fibres.

In drawing, 4 slivers are combined into one. Repeated drawing increases the quality of the sliver allowing for finer counts to be spun. Each sliver will have thin and thick spots. By combining, or doubling several slivers together a more consistent size can be reached. The slivers are separated into rovings. These rovings (or slubbings) are then what are used in the spinning process.

For machine processing, a roving is about the width of a pencil. The rovings are collected in a drum and proceed to the slubbing frame which adds twist, and winds onto bobbins. Intermediate Frames are used to repeat the slubbing process to produce a finer yarn, and then the roving frames reduces it to a finer thread, gives more twist, makes more regular and even in thickness, and winds onto a smaller tube.

Masson Mills

Over time the processes were refined. At Masson Mill and at Helmshore, there are Derby Doublers. The Masson machine, built by Platts of Oldham in 1902, doubled rovings from the breaker cards into card lap. This was then passed through the finisher card to produce the rovings This process was known as double carding. The Derby Doubler was patented by Evan Leigh of Ashton-underline ( 21 December 1810 - 2 February 1876) and though superceded still continued in service in condensing coarse counts.

The doubling process

Doubling of yarn where two or more stands or ends of yarn are twisted together. The spun yarn is wound onto a bobbin using a doubling winding machine, and two or more of these bobbins are placed on doubling frame (doubling winding machine). The ends pass through a series of rollers, as would be found in one of Arkwrights Water frames and twisted together onto one a bobbin using a spindle and flyer. (p=558)

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References

Notes

Bibliography

• Collier, Ann M (1970), A Handbook of Textiles, Pergamon Press, p. 258, ISBN 0-08-018057-4
• Nasmith, Joseph (1896), The Students'Cotton Spinning (3 ed.), Manchester: John Heywood, p. 638 {{citation}}: Invalid |ref=harv (help)
• Hills, Richard Leslie (1993), Power from Steam: A History of the Stationary Steam Engine, Cambridge University Press, p. 244, ISBN 978-0-521-45834-4, retrieved January 2009 {{citation}}: Check date values in: |accessdate= (help)CS1 maint: extra punctuation (link)