What are the production processes of Partially Oriented Yarn?

Partially Oriented Yarn (POY) is a crucial intermediate product in the textile industry, widely used in the production of various textile products. As a leading supplier of POY, I am delighted to share with you the detailed production processes of POY.

Raw Material Preparation

The first step in the production of POY is the preparation of raw materials. The primary raw material for POY is usually polyester chips, which are made from purified terephthalic acid (PTA) and ethylene glycol (EG) through a polymerization process. These polyester chips have specific properties such as high molecular weight, good thermal stability, and appropriate viscosity, which are essential for the subsequent spinning process.

Before being fed into the spinning machine, the polyester chips need to be dried to remove moisture. Moisture in the chips can cause problems during the spinning process, such as uneven melting and the formation of bubbles in the yarn. The drying process is typically carried out in a hopper dryer at a controlled temperature and for a specific duration to ensure that the moisture content is reduced to an acceptable level, usually less than 0.01%.

Melting and Extrusion

Once the polyester chips are properly dried, they are conveyed to the extruder. The extruder is a key piece of equipment in the POY production line, where the chips are melted and homogenized. Inside the extruder, the chips are heated to a high temperature, typically around 280 - 300°C, depending on the type of polyester and the desired properties of the POY.

As the chips are heated, they gradually melt and form a molten polymer. The molten polymer is then forced through a series of filters to remove any impurities or undissolved particles that could affect the quality of the yarn. After filtration, the molten polymer is extruded through a spinneret, which is a metal plate with numerous tiny holes. The size and shape of the holes in the spinneret determine the cross - sectional shape and fineness of the individual filaments in the POY.

Spinning and Cooling

As the molten polymer is extruded through the spinneret, it forms fine filaments. These filaments are immediately cooled by a stream of cold air in a quenching chamber. The rapid cooling process is crucial as it helps to solidify the filaments and prevent them from sticking together. The cooling rate affects the orientation and crystallization of the polymer molecules in the filaments, which in turn influences the physical and mechanical properties of the POY.

During the cooling process, the polymer molecules in the filaments start to align in a more ordered manner, but only to a partial extent. This partial orientation is what gives POY its unique properties. The filaments are then drawn down by a set of godet rolls at a specific draw ratio. The draw ratio is the ratio of the speed of the take - up godet to the speed of the extrusion. A typical draw ratio for POY production ranges from 2.5 to 3.5, which helps to further orient the polymer molecules and increase the strength and tenacity of the yarn.

Oil Application

After the filaments are cooled and drawn, they are coated with a special lubricant or oil. The oil serves several important functions. Firstly, it reduces friction between the filaments during subsequent processing, such as winding and texturing. Secondly, it helps to prevent static electricity buildup, which can cause problems in the handling and processing of the yarn. Thirdly, the oil can improve the smoothness and softness of the yarn, making it more suitable for use in various textile applications.

The oil is applied to the filaments using an oiling device, which can be a roller or a spray system. The amount of oil applied is carefully controlled to ensure that it is within the desired range, usually around 0.3 - 0.5% by weight of the yarn.

Winding

The final step in the POY production process is winding. The filaments are wound onto a bobbin or a package using a winding machine. The winding machine is designed to wind the yarn at a constant tension and speed to ensure a uniform and well - formed package. The winding process also needs to be carefully controlled to avoid problems such as yarn breakage, uneven winding, or excessive tension, which can affect the quality of the POY and its usability in downstream processes.

The wound POY packages are then inspected for quality control. They are checked for various parameters such as yarn count, strength, elongation, and appearance. Only the packages that meet the specified quality standards are approved for further processing or shipment to customers.

Applications of POY

POY has a wide range of applications in the textile industry. It is commonly used as a raw material for the production of drawn textured yarn (DTY), which is widely used in the production of clothing, home textiles, and industrial textiles. POY can also be directly used in some applications where a lower level of orientation and strength is required.

For more information about other types of yarns and textile solutions, you can visit our websites: Polyester Moisture Absorbing Quick Drying Yarn, Green Textile Solutions, and PVA Yarn.

Conclusion

As a POY supplier, we are committed to providing high - quality POY products through a well - controlled and efficient production process. Our understanding of the production processes of POY allows us to optimize the quality and performance of our products to meet the diverse needs of our customers.

If you are interested in our POY products or would like to discuss potential business opportunities, please feel free to contact us for procurement and negotiation. We look forward to working with you to achieve mutual success in the textile industry.

References

• Textile Yarn Manufacturing Handbook, Third Edition. By R. Postle, W. A. Oxenham, and P. J. Behery.
• Principles of Polymer Processing. By Z. Tadmor and C. G. Gogos.
• Handbook of Fiber Science and Technology. Volume III: High - Technology Fibers, Part A. Edited by M. Lewin and E. M. Pearce.