Heat-setting is a process that takes place during the yarn spinning before weaving the machine-made carpet on the fibers. In this process, the texture of yarns changes by heat and vapor, which eventually stabilizes and increases their quality.

Heat-set acrylic yarn
​The heat-setting process can apply to various fibers, including acrylic, polyester, polypropylene, and among the various types of yarns, the acrylic heat-set yarn has the highest quality. part of the heat-setting process involves giving water vapor to the yarn, which leads to an increase in the strength of the yarn, a decrease in the yarn fuzzing (acrylic yarn), and an increase in the dye ability, uniformity and softness of the yarn. The internal texture of the acrylic yarn heat-set during the spinning is stabilized by heat and vapor and, therefore, has less fuzz, more strength, and better quality. Also, the heat-set acrylic yarns are more durable due to the stability of the internal texture; as a result the carpets which weave with heat-set acrylic yarn have higher quality.

Advantages of machine-made carpet with heat-set acrylic yarn

Considering the higher quality of heat-set acrylic yarn than other yarns and also the high demand for this yarn in the Iranian machine-made carpet industry, the advantages of using heat-set acrylic yarn are examined. Increasing the quality of acrylic yarn through the heat-setting process causes the weaving of carpets that have the following distinctive features:

* By improving the quality of acrylic fibers due to heat setting, the fuzzing of acrylic carpet is greatly reduced.

* In the carpets weave with heat-set yarn, the yarn is seen separated, known as pomegranate seeds.

* The heat-set carpets have higher reversibility features and the so-called carpet traffic resistance is higher.

* The carpets which are woven with heat-set yarn have very low absorption of dust and contamination.

* The carpet becomes more uniform and the pattern and design of the carpet becomes more prominent.

* The color stability of the carpet is higher than others and the possibility of discoloration after washing the carpet (washing according to the instructions) is minimized.
* The heat-set yarns make the carpet more stable against indirect heat.

Ekbatan Carpet Company (A brand as valuable as machine-made carpet) an experienced manufacturer in the machine-made carpet industry uses 100% heat-set acrylic yarn in all products to produce high-quality carpets.