In view of the breakage, burr and other problems of the slitting machine in the process of hot stamping foil processing, the following is the troubleshooting and solution of the system:
First, the problem of bronzing foil breakage
Possible causes and solutions:
1. Improper tension control
◦ Cause: Excessive tension leads to excessive stretching of the foil, and too little tension makes it easy to loosen.
◦ Resolution:
▪ Check whether the tension control system of the slitting machine (such as magnetic powder brake, tension sensor) is normal.
▪ Adjust the tension parameters according to the thickness of the foil, usually the recommended tension of hot stamping foil is 1.5~3N/mm² (refer to the material supplier data).
▪ Ensure that the unwinding and rewinding tensions match, and the transition tension gradient should not be too large.
2. Worn or misaligned tools
◦ Cause: Blunt knife or tool holder offset can lead to uneven cutting and local stress concentration.
◦ Resolution:
▪ Replace sharp round or flat knives and check the shaft parallelism.
▪ Adjust the tool clearance (usually 10%~15% of the foil thickness).
3. Foil quality problems
◦ Cause: Insufficient toughness of the substrate or poor adhesion of the coating.
◦ Resolution:
▪ Replace the high-quality foil and check the batch for moisture or expiration.
▪ Test the breaking point at different speeds to see if it is a material limit issue.
4. The running speed is too high
◦ Reason: Tension fluctuations increase during high-speed slitting.
◦ Solution: Gradually reduce the slitting speed (e.g. from 200m/min to 150m/min) and observe whether it improves.
Second, the problem of burrs
Possible causes and solutions:
1. Insufficient sharpness of the knife
◦ Phenomenon: The cut is jagged or brushed.
◦ Resolution:
▪ Replace the tool immediately and choose a coated tool (e.g. diamond coating) to increase the life.
▪ Check the knife edge angle (usually 20°~30° is appropriate).
2. Slitting angle deviation
◦ Cause: The tool is not perpendicular to the direction of travel of the material.
◦ Resolution:
▪ Use the dial gauge to calibrate the tool holder to ensure that the verticality error < 0.02mm.
▪ For thin foils (<0.05mm), it is recommended to add guide rollers to stabilize the material path.
3. Auxiliary system failure
◦ Cause: Insufficient electrostatic adsorption or dust removal causes the foil to shake.
◦ Resolution:
▪ Install an ionizing air bar to eliminate static electricity.
▪ Clean the guide and pressure rollers to ensure that there is no dust or glue stains.
4. Temperature effects
◦ Cause: The foil softens due to high ambient temperature.
◦ Solution: Control the temperature of the workshop at 20~25°C and the humidity at 50%~60%.
Third, other frequently asked questions
1. Curling/warping
◦ Check whether the winding pressure is uniform, use taper tension control (reduce the starting tension by 10%~15%).
2. Horizontal stripes
◦ Check whether the guide rollers are eccentric or bearing wear, and make dynamic balance correction if necessary.
Fourth, maintenance suggestions
1. Daily inspection: tool status, tension parameters, guide roller cleaning.
2. Monthly maintenance: lubricate the knife shaft bearing, calibrate the sensor.
3. Record analysis: take photos and archive the fault phenomenon and establish a corresponding database of materials, parameters and quality.
Through the above steps, more than 90% of the hot stamping foil slitting problems can be systematically solved. If the problem persists, it is recommended to contact the equipment manufacturer for in-depth debugging of the servo system or PLC program.