1.What are the standards for compliance?
National/Industry Standards: Such as Chinese standards GB/T and YB/T, or international standards and customer standards.
Internal Company Standards: Usually stricter than national standards.
Customer-Specific Requirements: This is the most important standard; requirements vary greatly depending on the application of the strip (e.g., precision electronic components, general structural parts).
The method for measuring the camber is usually to place the strip on a platform and use a ruler to measure the maximum distance between its side edge and the straight edge of the platform.
2.How does the "amplification" effect of striping on the sickle curve occur?
Stress Release and Redistribution: Cold-rolled coils retain internal residual stress during rolling and coiling. When wide coils are longitudinally cut into narrow strips, this stress is released and redistributed, potentially causing the strips to bend to one side.
Slitting Machine Equipment Accuracy:
Disc Blade Accuracy: Excessive radial runout, axial clearance, or uneven blade wear can generate uneven lateral forces on the strip during cutting, directly "pushing" out a camber.
Guiding Device: Poor parallelism and alignment of the pressure plate and guide rollers can force the strip to bend during travel.
Tension Control: Unstable or uneven tension during slitting can cause the strip to deviate and bend during shearing and winding.
Process Settings:
Improper Overlap Setting: The overlap and gap between the upper and lower disc blades are unsuitable for the current material and thickness.
Slitting Position: If the master coil itself has shape defects such as "edge waviness" or "center waviness," different slitting positions will result in different camber patterns in the strips. Strips separated from the wavy area exhibit more pronounced camber.
Rewinding quality: Uneven winding (towering, overflowing edges) will cause new bends during subsequent unwinding.
3.How can we control it at the source?
Use a master roll with a camber and a qualified sheet shape. This is the most important prerequisite.
4.How can the process be optimized?
Optimize blade clearance, overlap, and slitting speed based on material thickness and hardness.
Set appropriate and stable front and rear tension.
For products requiring high precision, consider using a precision slitting machine with an online camber correction device (such as a side camber roller).
5.What practical suggestions do you have?
First, confirm the exact standard you are applying (customer standard or internal standard).
Measure and record the camber data of the master coil before slitting.
Compare the camber data of the sliver after slitting.
If the camber deteriorates significantly after slitting, the problem is likely with the slitting equipment's accuracy or process parameters, requiring investigation and adjustment in both areas.