I. Understanding the Core Principle of Taper Tension
Taper tension refers to a control method where, during the winding process, the tension gradually decreases according to a set ratio as the roll diameter increases. Its purpose is to compensate for the accumulation of interlayer pressure caused by the increase in roll diameter, preventing damage to the inner layer material or loosening of the outer layer.
Typical Control Mode: Uses the "initial tension + taper coefficient" method. For example, if the initial tension is 100N, the tension decreases by 5% for every 10cm increase in roll diameter.
Mathematical Expression: Taper Tension = Tension Setpoint × (1 - Taper Coefficient × (1 - Minimum Roll Diameter / Current Roll Diameter)).
Control Type Selection: When the tension controller is used for winding, it should be set to taper tension control mode; when used for unwinding, it is usually set to constant tension mode.
II. Setup Steps and Key Parameter Configuration
1. Confirm Basic Parameters
Set the initial tension: This can be estimated using the formula Tension (N) = Material Width (m) × Setting Coefficient (N/m). The specific coefficient needs to be determined based on the material's tensile strength.
Determine the minimum roll diameter (e.g., 76mm or 152mm) and the maximum roll diameter (generally 90% of the mechanical limit).
2. Configure the Taper Coefficient
The larger the taper coefficient, the faster the tension decreases with increasing roll diameter. The industry standard for straight taper settings is a decrease of 3%~5% per layer.
Curved tapers are suitable for more precise applications, gradually reducing tension under near-constant torque conditions for a smoother transition.
3. Calibrate the Roll Diameter Detection Device
Ensure the proximity switch is correctly installed and functioning properly for real-time measurement of roll diameter changes.
Manually run the system to verify the accuracy of the roll diameter readings. If abnormalities are found, return to check the sensor wiring or location.
4. Enable Taper Control
Select the "Taper Tension Control" mode in the tension controller, input the initial and final values, and the system will automatically calculate the attenuation curve.
Use a controller that supports 0-10V or 0-24V output, compatible with frequency converters, servo systems, or magnetic powder clutches.
5. Dynamic Monitoring and Adjustment
Install a floating roller at the pre-lamination station to monitor tension fluctuations. If the fluctuation exceeds ±5mm, adjust the parameters immediately.
Enable the "Soft Start" function; the tension will be reduced to 70% of normal during roll change, and restored after 2 seconds to prevent film breakage.
III. Material Compatibility and Practical Recommendations
1. Film Materials (e.g., EVA, PO, PET): Recommended tension range 2~5kg. Excessive tension will cause translucency, while insufficient tension may cause bubbles or loose winding.
2. Fabric Materials (e.g., non-woven fabric, fleece): Control tension ≤3kg to avoid fiber deformation. During adjustment, use the absence of wavy wrinkles at the edges as a benchmark.
3. Sensitive materials (such as optical films and aluminum foil): A closed-loop tension control system is recommended, combined with stable ambient temperature and humidity control, to reduce the impact of tension fluctuations.
4. Paper materials: A linear setting of 0.1~0.5 kg/cm can be used, combined with paper width and basis weight calculations to determine power requirements, ensuring tight winding without crushing.
