How to select polypropylene POY yarn? Before purchasing, make sure to clarify these two issues first. 

 polypropylene POY yarn (pre-tensioned yarn) is a semi-finished form of polypropylene filament yarn, mainly used for subsequent processing to produce DTY (stretch and deformation yarn) or for specific weaving. Many purchasers often encounter confusion when selecting types: What are the differences between POY yarn and FDY yarn? What indicators should be focused on during the purchasing process? Below, starting from two common questions, we will help you clarify your thinking. 

1. POY filament and FDY filament: Different purposes, cannot be directly substituted 

This is a point that is relatively easy to get confused in procurement. Although both are polypropylene filament, they differ in the production stage and application purpose. 

POY filament is a semi-finished product: After being spun at high speed, it is wound into a form. It has moderate orientation and a relatively low crystallinity. It cannot be directly used for weaving and needs to undergo reeling (false twisting deformation) or stretching processing to obtain usable DTY filament or stretched filament. It is suitable for products that require a fluffy feel, such as carpet yarn, decorative fabrics, and some textile and clothing fabrics. 

FDY yarn is a finished yarn: After spinning, FDY yarn undergoes stretching and shaping directly, and already has high strength and stable elongation rate. It can be directly used for weaving luggage straps, industrial fabrics, etc. When purchasing, please judge according to your downstream equipment: if there is only a loom but no beam winding machine, choose FDY yarn or stretched yarn; if there is a beam winding machine, you can choose POY yarn for post-processing. 

It should be noted that there will be significant differences in feel, strength, and elongation between POY filament of the same specification and DTY filament obtained through post-processing. When purchasing POY filament, it is recommended to clearly specify the final product's purpose at the same time, so that the supplier can recommend the appropriate raw material specification. 

II. Quality of POY Silk: Focus on these aspects 

The quality of POY filament directly affects the smoothness of the subsequent drawing process and the performance of the finished DTY. When purchasing, you can pay attention to the following aspects: 

Thread uniformity (CV value): This refers to the uniformity of the thickness of POY yarn in the length direction, which is the core indicator for measuring its quality. Thread unevenness can lead to significant tension fluctuations during the subsequent drawing process, potentially resulting in fuzziness or uneven dyeing. Whether the supplier has the capability to test thread uniformity is a reference for evaluating their quality control level. 

Winding forming quality: The hardness, end face flatness, and unwinding property of the POY filament rolls. Poorly formed POY filaments will frequently break off when unwound on the drawing machine, affecting production efficiency. When purchasing, it is recommended to request samples for on-machine trial use to observe whether the unwinding is smooth. 

Elongation and elongation CV value: The elongation of POY filament is usually around 120% - 150%. Excessive elongation or too low elongation will affect the subsequent stretching matching. The elongation CV value reflects the amplitude of elongation fluctuations within the same batch, and the smaller the value, the more stable it is. 

Oil content: The oil content on the surface of POY filament affects its bunching property and anti-static performance. A too low oil content is likely to cause static electricity and frayed fibers, while an excessively high oil content may cause smoke and coking during the subsequent drawing process. The supplier can adjust the oil formulation and content according to your drawing process. 

Summary and Selection Suggestions 

When purchasing  polypropylene POY yarn, it is recommended to follow the steps below for confirmation: 

Confirmed post-processing steps: Is there a beam winding machine? What is the final product - carpet yarn, decorative fabric or something else? Different applications correspond to different POY filament specifications (filament count, elongation range). 

Focus on quality indicators: Request the test reports for the fineness uniformity and elongation CV value of the recent batches. If possible, take samples to test on the loom to observe the breakage rate and the amount of fuzz. 

Clarify the color requirements: If you need to color the POY filament with the original liquid color, please provide a color chart or Pantone number, and confirm the supplier's control standard for color variations between batches. 

Ningbo Dazhong Industrial Fibre Co., Ltd. was founded in 1984. It produces 15,000 tons of products such as polypropylene POY yarn, polypropylene FDY yarn, polypropylene stretching yarn, and polypropylene coloured yarn annually. It has the right to handle import and export business. Please feel free to send samples for testing and communicate your specific requirements. 

Official website: http://www.dzfibre.cn 

Contact Information:

Contact person: Mr. Chen  Mobile phone: 13805815865 

Fax: 0574 - 6355073 

Email: dz@dzfibre.cn 

Address: Industrial Development Zone, Qiaotou Town, Cixi City, Zhejiang Province