Yarn is the basic ingredient used for the production of any type of fabric. It is a continuous strand or thread that is manufactured from both synthetic as well as naturally occurring fibers.
The fibers or raw materials are twisted together by spinning process and turned into elongated filaments to produce the yarn.
The type of yarn that is used in the production process determines the quality and type of fabric that is produced at the end. So, a lot of importance is given to the selection and manufacturing of the best quality yarns across the world.
Yarn may be produced through different processes and methods. Some of these are highlighted in the discussion below.
The Raw Materials
Textile and fabric manufacturing requires fibers that have the appropriate length, diameter, fineness, flexibility, and strength. The yarn which is the building material for fabric requires these fibers as raw material.
Other important characteristics to analyze before selecting a fiber for yarn manufacturing include
- The waviness
- Ability to absorb moisture
- Thermal resistance and heat withstanding capability
- Reaction to various chemicals, detergents and cleaning agents
- Natural Fibers
There are certain naturally occurring fibers in the world including those that are extracted from plants and animals.
Examples of natural fibers include
- Synthetic Fibers
Fibers that are man-made are called synthetic fibers. These may include
The raw material of the yarn, the fiber, is fed into the spinners to manufacture the resultant product. It sounds like a simple process, but is quite costly and critical.
The Spinning Process
- Ring Spinning
This is one of the oldest used methods of yarn production. It involves some basic steps including
- A big mass of fiber called sliver is taken
- It is passed through the drafting process and reduced in size
- Twisting of the fibers is done to strengthen it
- The final product is spun onto the bobbin.
It is a commonly used process but is considered to be slow and time consuming as compared with latest spinning methods.
- Rotor Spinning
This is a process called the open end spinning method of yarn manufacturing. It has a spinning rotor as the main component that uses slivers to spin yarn in a direct manner.
There is a withdrawal system that creates the twisting motion leading to the production of the yarn.
As compared with ring spinning this is a less complicated process and takes very little time. However, the yarn produced by this method has lesser strengthen and smaller range.
- Air-Jet Spinning
This process involves a drafting system into which a sliver is fed into. This forwards the yarn to the vortex that is formed by air jets moving at very high velocity. A twist hence created leading to the formation of the yarn.
It is a popular form of yarn production because of its high speed and greater productivity. This process is appropriate for producing yarns of range above 24/1sizes.
In all the above mentioned processes the fibers are held together by one characteristic called twisting. It is vital for determining the strength of the yarn and its other essential properties.
The Twisting Process
It is a process that helps in the conjoining of the fibers and twisting them around each other to make a single continuous strand of thread or yarn. Threads are produced by the combination of the fibers while the twisting of the threads lead to the formation of the yarn.
The Plying Process
Once the thread has been produced by the twisting of the fibers, the threads are conjoined together to form a given range of yarn. Ply refers to the number of threads that are utilized to produce a given yarn.
Plying is done in the opposite direction of the twisting.
Different types of fabrics require different plies of yarn. A single ply yarn is used for very light weighted and thin fabric production. Common example is of organza.
The greater the ply numbers the stronger and thicker the fabric becomes.
Other types of Yarn that may not require twisting
- Filament yarn
Yarns that do not require any twisting are called filament yarns. They are already quite long and have greater amount of luster on them.
These are mostly artificial or man-made fibers. Silk is the only natural fiber that produces filament yarn.
- Spun Yarn
This type of yarn is also usable without undergoing the process of twisting. They are less lustrous than filament yarns but are softer. They do not have very high strength and are also less elastic in nature.
The Reeling Process
A silk filament or fiber is produced naturally in an insect cocoon. The process by which the filament is unwound and directly rolled on to the holder is called reeling.
The Throwing Process
If the silk strands or filaments are twisted together to produce thicker yarn, this process is known as throwing.
Final Yarn Packaging
The packaging of the yarn manufactured depends on its type and intended use. Below are some of the shapes and forms that finished yarn can be made available to the fabric manufacturers.
Bobbins are cylindrical reels or cores that are made from various materials like cardboard, metal, plastic or wood. The prepared yarn is wound around these bobbins to securely store them and avoid entangling.
They have the ability to be put on to the machine and spindles for ease of use.
These are also cylinder shaped yarn holders but they have flanges on the ends.
As the name suggests, these yarn holders are cone shaped and are widely used for storing the yarn without any entangling or loss of strength.
These are cylinder shaped yarn holders that require the yarn to be winded on tube structures. They are higher and larger than regular yarn packages.
When yarn is wound around itself without a core it is called a skein packaging.
They are large sized packs that have the shape of a barrel. They are used for holding the weft yarn during the process of weaving.
These are smaller than the pirns but are used for the same purpose of holding the weft yarn during weaving.
They are made from metal or wood and are cylindrical in shape. With a ten inch diameter the beams can be as long as five feet. They are ideal for holding the warp yarn during the weaving process.