Transport Frequency
Fluid transport rates in dyeing machinery determine the frequency at which the dye bath makes contact with the substrate surface. The liquor circulation velocity governs the exchange rate between the bulk solution and the boundary layer surrounding the yarn or fabric. High speeds reduce the risk of unlevel results by maintaining a constant concentration gradient across the entire batch.
Kinetic Transfer
Movement of the dye molecules toward the fibre is accelerated by the mechanical force of the pump. A higher liquor circulation velocity ensures that the temperature remains uniform throughout the vessel. This prevents cold spots where the dye would fix more slowly than in the rest of the machine.
Pump Displacement
Mechanical settings on the dyeing machine control the volume of water pushed through the fabric every minute. Adjusting the liquor circulation velocity is necessary when changing from a heavy cotton to a delicate silk to avoid damaging the textile. The speed must be high enough to ensure penetration but low enough to prevent pilling or abrasion.
Levelness Result
Assessment of the finished garment often reveals whether the flow was sufficient during the heating cycle. If the liquor circulation velocity was too low, the dye may appear deeper on the outer layers of a yarn package than on the inside. Correct flow settings are the primary defense against internal shading variations.
