Influence of Warp Cover Factor on Dye Circulation in Jet Processing
High warp cover factors reduce fabric liquid permeability, requiring wider rectangular nozzles and slower heating ramps to prevent surface shade unlevelness.
Airflow Jet
Nozzle Technology
Pneumatic dyeing equipment utilizes high-velocity gas streams to transport rope-form fabrics through processing chambers without relying on large volumes of liquid carrier. Within this machinery, an airflow jet accelerates the gas through a venturi tube to generate the force required to move the textile rope at speeds up to six hundred meters per minute. The dye liquor is introduced as a highly dispersed aerosol directly into the high-velocity air stream, coating the passing textile evenly.
This pneumatic system replaces the traditional hydraulic drive, which reduces the total water consumption of the dye cycle by more than fifty percent and lowers the overall discharge of saline effluent to treatment plants.
Transport Mechanism
Liquid dye is atomized directly into the gas stream before it meets the moving fabric rope. An airflow jet relies on the rapid expansion of gas to distribute these fine droplets evenly across the yarn surfaces, ensuring rapid diffusion without soaking the material in a continuous bath. This gas-driven circulation prevents surface abrasions that can occur when heavy fabrics are dragged through traditional liquid-filled tubes.
Aerosol Delivery
Mist injection requires highly controlled nozzle diameters to maintain a stable gas velocity and prevent premature droplet coalescence. When the airflow jet operates at peak pressure, the micro-droplets penetrate the yarn core quickly, achieving high color yield with minimal mechanical agitation. The flow velocity is modulated based on the fabric weight to prevent filament breakage in delicate synthetic yarns.
Fabric Application
High-performance synthetics and dense cotton knits represent the primary substrates treated with this technique. Because the airflow jet does not submerge the fabric, it cannot be used for materials that require heavy lubrication to prevent creasing. The process is also unsuitable for very open structures that allow the gas stream to pass through without generating sufficient drag to move the rope.