1.What are the consequences if burred strips are used directly for stamping?
Causes cracking: Micro-cracks exist at the root of the burr; these cracks propagate during stamping and stretching, leading to direct breakage of the part.
Die damage: Hard burrs accelerate die wear, potentially causing chipping.
Impact on positioning: Edge burrs cause uneven feeding of the strip, resulting in inaccurate positioning.
Therefore, burr removal for cold-rolled coils used in stamping must be addressed at the slitting stage.
2.How to prevent it in the early stages?
Check for continuity: If the burrs are continuous and uniform along the entire edge, the direct cause is a dull tool; immediately replace the tool or resharpen it.
Check for periodicity: If the burrs are intermittent or have bright spots, the cause is chipped cutting edge; the machine must be stopped for resharpening or the blade must be replaced.
Gap adjustment: During adjustment, at least four points must be checked along the circumference of the tool shaft to ensure uniform gap.
3.How can the accuracy of the equipment be guaranteed?
Cutter shaft radial runout: Must be <0.01mm; otherwise, runout will cause momentary deviations in overlap, resulting in large localized burrs.
Pressure plate/guide device: The movable pressure plate must extend to the shearing edge. Uneven wear on the pressure plate will directly cause deformation of the material before shearing, resulting in burrs even with perfect cutters. Timely repair is necessary.
4.How to adjust dynamically?
Initial Inspection: After threading the tape, cut 1-2 meters, stop the machine, and measure using a 100x magnifying glass with a light source or a dedicated deburr tester. Only increase speed if it passes inspection.
Mid-Process Monitoring: Check the cutting edge condition every 50-100 kilometers or when changing the steel coil grade.
Tension Control: Tension fluctuation during slitting should be <±5%. Uncontrolled tension will cause severe compression and deformation of the strip on the burr side during winding, producing "secondary false burrs."
5.What are some recommendations for stamping applications?
Source Control: Clearly define the acceptance standard with slitting suppliers as "burr height ≤ 0.02mm, and visually inspected for no flanging or bright spots." This standard exceeds general national requirements, but is necessary for automated stamping.
Incoming Material Inspection: Use a 20x magnifying glass to randomly inspect the edges of each batch of incoming materials. If the burrs detected are > 0.05mm, reject the entire batch.
Die Protection: If, due to objective conditions, materials with slight burrs must be used, it is recommended to add TD treatment or PVD coating to the stripper plate inserts or die cutting edges of the stamping die to improve wear resistance and act as a buffer.