Twisting

from Wikipedia, the free encyclopedia

As twisting , the twisting together yarns or twisted yarns to a yarn, the twisting referred to twisting machines.

According to the intended use, one can distinguish between two broad groups: plain threads , which are mainly produced to improve tear resistance and evenness, and fancy threads, which are intended to beautify a textile or liven up a pattern in the end use.

Both staple yarns and filaments of the same material, fineness and color as well as different types of yarn are suitable for twisting together.

history

The oldest remnant of a rope or cord, 30 centimeters long and a total thickness of 6 to 8 millimeters, found so far was discovered in 1953 by André Glory in the Lascaux cave and dates back to 15,000 BC. Chr., Already consists of three yarns made of plant fibers, each twisted simply in the Z-direction, which in turn were twisted together in the S-direction.

Twist

Twist twist: S-wire and Z-wire

The direction and number of twists are important for the character of the thread , both in terms of the template (i.e. the single thread) and of the twisted yarn . If the direction of the spiral is the same as the slash in the letter "Z", it is called a Z-twist or Z-wire. Twists that follow the direction of the middle part of the letter "S" are threads with an S twist or S wire.

Single yarns are usually made in Z-wire and twisted threads in S-wire .

If the direction of the twist is the same as the twist, the result is a very hard twist (suitable for tire cords, for example ).

With an increasing number of twists, the tensile strength of the thread increases to a certain extent (around 20%).

Smooth threads

The main purpose of twisting is to improve tear strength and evenness. Twisting is essential for yarns for many warps (especially made of pure wool ), sewing yarns and chains for tire cord.

Preparatory process

  • Staple yarns tend to loop. To avoid this, yarns are steamed at 60–80 ° C for 15–30 minutes before being twisted .
  • Blasting with emulsion (approx. 0.5% of the yarn weight) made of fatty acid.
Purpose: to reduce yarn wear during further processing
  • The template for the twisting machine usually consists of plied yarn, that is, 2–6 threads are wound onto a bobbin as one strand.
Two-for-one twisting machine, built around 1975

The twisting

The best known are the following four processes: two-for-one, ring and step twine and, for special purposes, cabling , whereby the two-for-one process is used to produce most of the smooth twines.

Function of the double wire machine:

The template is placed on the hollow spindle (1) in the fixed pot (2). The yarn runs from above through the spindle down, on the outer wall of the pot to the thread guide (3) and on to the winder (4). With each revolution of the spindle, the yarn receives one rotation between the supply package and the tip of the hollow spindle and a second between the lower spindle exit and the thread guide.

The two-for-one machines can achieve around 12,000 spindle revolutions per minute.

Ring or step twisting machines are better suited for twisting smaller lots and for some special uses.

Fancy threads

As a rule, a fancy thread is formed from

Fancy threads
  • Basic thread (single thread or twisted thread)
  • Effect thread or fiber sliver (tied in regularly or irregularly)
  • (possibly) fixing thread (single or twisted)

The effects will be

  • wrapped around the basic thread, resulting in bouclé , loop , frottée , onde, etc. Ä.
  • tied between two basic threads in chenille , knobs , flame, etc. Ä.

The picture on the right shows (from left to right): bouclé , loop , knobs and onde .

Crepe threads are sometimes assigned to fancy threads. These are smooth threads with excessive twist, which, when used in the fabric, produce a particularly robust surface ( chiffon , crepe de chine , crepe georgette, etc.).

PAN decorative fabric made of filament in the warp and chenille (360 tex ) in the weft

Use of fancy threads: decorative fabrics, hand embroidery threads, fashionable woven and knitted fabrics and as single threads for fashionable effects in all kinds of textiles.

Manufacturing

Most of the fancy yarns are produced on ring twisting and hollow spindle machines.

The feed rollers are adapted for continuously variable speed. A drafting system is also installed on some machines, which can deliver fiber slivers of different strengths.

Twisting on ring twisting machines is often carried out in 2–3 passages, and the finished yarn is usually wound on packages.

On modern hollow spindle machines, the fed thread (or threads) is passed through the hollow space of the spindle and twisted with a twist hook. The rotation is fixed at the same time with a thread from the cop placed on the spindle. The rotations of the spindle can differ from the speed of the twist element and thereby significantly influence the look and feel of the thread.

Combinations of the hollow spindle and ring twisting process are also known. Manufacturers of special machines for fancy twisting offer systems that allow patterning in up to 2000 variants.

literature

  • Anton Schenek: Lexicon of yarns and twisted threads . Deutscher Fachverlag, Frankfurt am Main 2005, ISBN 3-87150-810-1 .
  • Fabia Denninger, Elke Giese, Herbert Ostertag: Textile and fashion dictionary. Deutscher Fachverlag, Frankfurt am Main 2006, ISBN 3-87150-848-9 .

Individual evidence

  1. ^ Alois Kießling, Max Matthes: Textile - specialist dictionary. Fachverlag Schiele & Schön, Berlin 1993, ISBN 3-7949-0546-6 , p. 428.
  2. ^ Elizabeth W. Barber: Women's work. The first 20,000 years. Women, cloth and society in early times . Norton & Comp., New York / London 1994, ISBN 0-393-03506-9 , pp. 51-52.
  3. ^ Elizabeth W. Barber: Prehistoric textiles. The evolution of cloth in the neolithic and bronze ages with special reference to the Aegean . Princeton 1992, ISBN 0-691-00224-X , p. 40.

Web links