In traditional textiles a tenter frame would carry woven fabric through an oven to heat set
the fabric or keep it from shrinking during drying. In nonwovens, the primary use for a
tenter frame is to stretch the fabric in the cross machine direction and/or hold the fabric
while it is heated with an infrared heater to keep the polypropylene and/or polyester fibers
in the fabric from shrinking the fabric under heat. Stretching the fabric in the cross ma-
chine direction enables the production of wider fabric. For instance, fabric on a 5 meter
production line could be stretched to 6 meters wide. Stretching the fabric in the cross ma-
chine direction also affects the cross machine tensiles, elongation, trap tears, and other
characteristics of the fabric.
The fabric is carried through the tenter frame by a chain on the sides. There are pin plates
attached to the chain. The pin plates have 1/2 to 3/4 inch long pins that stick up vertically
and pierce through the edges of the fabric. An automatic guide system at the entrance to
the tenter frame tracks the edges of the fabric and makes sure the fabric and pin plates are
in a proper position for the pins to catch the edges of the fabric.