High-quality polyester (PET) chips are primarily used. Vacuum drying prevents hydrolysis during high-temperature melting, ensuring the mechanical strength of the filaments.
Ingredients and extrusion SOP
2
Melt Extrusion Screw Extruder
The dried chips enter the screw extruder, where high temperature and mechanical shearing melt the solid chips into a uniform polymer melt.
Precision stamping SOP
3
Spinning and Drawing
This is the key step that distinguishes filament geotextiles from staple filament geotextiles: spinning.
Lateral stretching SOP
Longitudinal stretching SOP
4
Yarn Spinning and Web Formation
The drawn filaments vibrate and disperse under the action of airflow.
Roll forming and testing SOP
5
Mechanical Reinforcement (Needle Punching)
Pre-needle punching and main needle punching: The loose fiber web enters the needle punching machine, causing the fibers to intertwine and lock together.
Roll forming and testing SOP
6
Edge Trimming, Rolling, and Inspection
Heat Setting/Singeing (Optional): Depending on customer requirements, surface heat rolling or singeing may be performed to improve fabric smoothness or control thickness.