1.What are the consequences of improper cutting?
If traditional shearing (such as ordinary shearing machine) is used, if the blade is not sharp enough and the gap adjustment is unreasonable, the edge of the plate will be squeezed and deformed, causing the coating to crack and peel off (especially for products with brittle coating or poor adhesion).
If the plate is not fixed stably during high-speed cutting, sliding friction will occur, causing the coating surface to be scratched.
2.What are the consequences of insufficient equipment accuracy?
Wear or positioning deviation of cutting equipment (such as blades and press devices) may result in uneven cutting edges, the coating being "torn" by the blade instead of being cut cleanly, resulting in coating shedding or burrs with coating debris.
3.What impact do coating performance limitations have?
When the coating has low hardness and insufficient flexibility (such as some economical polyester coatings), it is easy to crack under the pressure of cutting;
When the coating has poor adhesion to the substrate (such as improperly pre-treated products), the stress during cutting will cause the coating to separate from the substrate.
4.What are the key measures to reduce coating damage?
Choose the right cutting method
Precision shearing or laser cutting is preferred: laser cutting separates the plates by high-temperature melting, with smooth edges and almost no damage to the coating; precision shearing can achieve "cold cutting" through sharp blades and reasonable gaps, reducing coating extrusion.
Avoid using friction cutting methods such as grinding wheel cutting, which will generate high temperatures and debris, directly burning or scratching the coating.
Optimize equipment and operation ◦ Ensure that the blade is sharp and the surface is smooth, and polish or replace it regularly; fix the plate firmly through the pressing device during cutting to avoid sliding friction; control the cutting speed, especially for thick plates (such as ≥0.8mm), which can easily cause the coating to bear excessive instantaneous stress if it is too fast.
Adaptability of the coating itself ◦ Coatings with high adhesion and high flexibility (such as fluorocarbon coatings and highly weather-resistant polyester coatings) are more resistant to cutting damage, and their elasticity can buffer cutting stress and reduce the risk of cracking; ◦ The coating thickness must be uniform, and too thin coatings (such as <5μm) are more easily damaged at the edges.
5.Can damage be reduced through process control?
Laser cutting or precision shearing, combined with sharp knives and stable operation, can achieve "damage-free" cutting;
If there is slight edge coating damage (such as local burrs), it usually does not affect the overall use (the edges can be processed later, such as repainting), but large-area coating peeling should be avoided (which will affect the anti-corrosion performance).