Conveyor Assembly
Mechanical guidance systems in long drying or curing ovens secure the fabric margins using rows of sharp needles mounted on moving belts. This mechanism is pin chain transport, and it maintains fabric width and alignment during thermal treatment on a stenter frame. It prevents the fabric from curling or shrinking during high-temperature air circulation.
Lateral Tension
Retractable pins penetrate the selvages of the fabric as it enters the drying chamber to hold the material under tension. The distance between the parallel chains can be adjusted along the length of the oven to stretch or relax the fabric. This control is necessary to achieve the correct finished width of the cloth.
Drying Run
Air nozzles blow hot air onto the suspended fabric as it moves through the drying compartments on the conveyor. Because the fabric is secured along both margins, it remains flat and uniform. In synthetic blends, this controlled environment allows the polymers to achieve heat-setting temperatures without uncontrolled dimensional distortion.
Feed Rate
Overfeed devices feed the fabric onto the pins at a speed slightly faster than the chain speed to allow for relaxation in the warp direction. This overfeed reduces the length shrinkage of the finished fabric. If the overfeed is too low, the fabric will be under tension in both directions, which leads to high residual shrinkage when the garment is subsequently washed.
Correct overfeed settings on the pin chains ensure that the knit loops are allowed to relax, resulting in a stable and high-quality finished garment.
