Slitting burr control: clearance, knife condition and tension
Burr on slit stainless strip mostly comes from knife clearance, knife wear and tension variation. Start with 5%–8% of thickness, then check knives, tension and incoming strip.
Burr height after slitting directly affects downstream stamping, welding and appearance. Three factors dominate:
1) Knife clearance: typically set at 5%–8% of strip thickness — smaller for hard or thick material, larger for soft or thin material. Uneven clearance produces a heavier burr on one side.
2) Knife condition: worn or chipped edges amplify burr; change or regrind knives on a schedule based on output and material, and record edge condition.
3) Tension and alignment: tension fluctuation and strip misalignment cause wavy edges and uneven burr. Check centring and coiling tension before winding.
Other influences:
• Incoming strip shape and thickness tolerance: wedge and edge waves change the effective clearance.
• Grade and hardness: soft 304 and hard-tempered 301 need different settings.
• Line speed: too high accelerates wear and burr.
Acceptance advice: agree a maximum burr height (for example ≤5% of thickness), the measurement positions and frequency, and tighten inspection at first piece and after knife changes.
When burr appears, check clearance and knife edges first, then tension and incoming strip — this usually locates the cause quickly.
