Yarn Conditioning

Textile fibers are subjected to various physical operations to make in to a yarn. For example cotton fiber passes through opening, carding, drawing and spinning to become a yarn. During these phases the original moisture content on the fiber would have been lost and some static electricity would be carried by the fiber. The amount of static current carried by yarn changes from fiber to fiber. Similarly the strength of any fiber depends up on how close the present moisture content is to the original natural value.

Similarly some high twist yarn would tend to loose its twist as and when it is allowed freely, making a lengthwise elongation.

Some fibers would tend to shrink when exposed to hot atmosphere or any treatment that involves heat and hence higher temperature. For example polyamide, polyester etc.

Some blends like Cotton/Lycra, Viscose/Lycra require conditioning to make the width the fabric stable.

So all the above said factors, if not addressed properly would reflect badly on the final quality of yarn or fabric. A process that addresses all the above parameters is called Conditioning. Therefore the aim of Conditioning is to provide an economical device for supplying the necessary moisture in a short time, in order to achieve a lasting improvement in quality.

Conditioning Process for Various Yarns

100% Polyester yarn:

Load the yarn in the form cones wound on plastic cones, in to a beam dyeing machine. Introduce steam and raise the temperature to 100°C at 3°C per minutes. Steam for 15 minutes at 100°C followed by 15 minutes cooling = 1 cycle. Repeat the cycle for 4 times.

100% Nylon:

Load the yarn in the form cones wound on plastic cones, in to a beam dyeing machine. Introduce steam and raise the temperature to 100°C at 3°C per minutes. Steam for 15 minutes at 100°C followed by 15 minutes cooling to a temperature of 50°C = 1 cycle. Repeat the cycle for 4 times.

Silk yarn:

Load the yarn in the form cones wound on plastic cones, in to a beam dyeing machine. Introduce steam and raise the temperature to 70°C at 3°C per minutes. Steam for 15 minutes at 70°C followed by 15 minutes cooling to a temperature for 30°C = 1 cycle. Repeat the cycle for 4 times.

Cotton/Lycra (40's Lycra) or Viscose/Lycra (60's):

Load the yarn in the form cones wound on plastic cones, in to a beam dyeing machine. Introduce steam and raise the temperature to 70°C at 3°C per minutes. Steam for 15 minutes at 70°C followed by 15 minutes cooling to a temperature for 30°C = 1 cycle. Repeat the cycle for 4 times.

Benefits of Conditioning:

For Knitting:

The treatment temperature for knitting yarn is held below the melting point of the wax. Temperatures for unwaxed yarn are coordinated to the compatibility for each individual type of yarn.

• Upto 20% greater efficiency due to a reduction in the unwinding tension
• Fewer needle breaks
• Uniform moisture content and friction values
• Regular stitch formation
• No change in size of finished articles
• No extra dampening required
• Free from electrostatic
• Less fly hence less problems. It helps if the yarn is running on a closer gauge machines.

NOTE: The wax applied should be able to withstand min 60 degree centigrade. If low quality wax is used, it will result in major problem. Conditioning should be done at 55 to 60°C.

For Weaving:

• Upto 15% fewer yarn breaks due to greater elongation
• Less fly, resulting in a better weaving quality
• Increased strength
• Increased take-up of size, enhanced level of efficiency in the weaving plant
• Softer fabrics

For Twisting:

• Conditioning and fixing of the twist at the same time in a single process.

For Dyeing:

• No streaks
• Better dye affinity