Why Does The Ultrasonic Lace Machine Wrinkle The Fabric When Welding It?

1. Mismatch in material properties
Reason: When the fabric is too thin, elastic (such as needle woven fabric, stretch fabric), or contains synthetic fibers, high-frequency vibration can easily cause fiber shrinkage or displacement.
solve:
Choose fabrics suitable for ultrasonic welding, such as thermoplastic fibers like polyester and nylon.
Pre heat set the elastic fabric or reinforce it with lining fabric.

2. Uneven or excessive pressure
Reason:
Excessive pressure on the welding head (mold) causes deformation by squeezing the fabric.
Uneven pressure distribution (such as non parallel welding head and bottom mold).
solve:
Adjust the pressure to a moderate level (balancing welding strength and fabric deformation).
Check the parallelism between the welding head and the bottom mold to ensure even contact.

3. Improper vibration frequency or energy
Reason:
Excessive energy: Overheating causes fabric to shrink or melt excessively.
Insufficient energy: The welding is not firm and requires repeated processing, which exacerbates wrinkling.
solve:
Adjust the ultrasonic amplitude (usually 20-35kHz) and welding time (0.1-1 second) according to the thickness of the fabric.
Test parameters (energy, pressure, time) on the sample first.