1.What are the measures to prevent deformation of galvanized steel processing?
Optimize blanking and layout
Laser/plasma cutting: Use micro-connection points to prevent small panels from falling off and deforming.
Add stress relief grooves (width ≥ 2 times the thickness of the plate) when nesting layout.
Punching: The mold gap is controlled at 8%~12% of the plate thickness.
Bending process adjustment
Mold compensation design: Lower mold V-mouth width = 6~8 times the material thickness.
Upper mold R angle = plate thickness × 1.2.
Protect zinc layer: Mold is hard chrome plated to reduce friction
Apply PE protective film to prevent scratches
2.What are the methods for correcting deformation?
Mechanical correction
Roller leveling machine: Applicable: thin plate (0.5~3mm) wave deformation
Roller spacing ≈ plate thickness × 20, multi-pass progressive leveling
Hydraulic shaping: thick plate (＞4mm) uses a press of more than 200T, with a three-dimensional adjustable mold
Local heat correction
Flame correction: Oxyacetylene neutral flame (temperature ≤ 250℃)
Triangle heating method: side length 30~50mm, interval 100mm
Vibration Stress Relief (VSR)
Applicable to large welded structural parts
Frequency range: 50~150Hz, amplitude 0.5~1mm, treatment time 10~20 minutes
3.How to deal with special processing scenarios?
Drilling/tapping deformation:
Solution: Pre-punch the pilot hole (hole diameter = 60% of the final hole); Coated drill (TiAlN) speed ↓30%, feed ↑20%; Spray water-soluble cutting fluid (chlorine is prohibited).
Process chain optimization: Pre-straightening force = 120% of final deformation
Aging treatment: Baking at 80℃ for 2 hours to release stress
4.What are the key points of zinc layer protection?
Temperature red line: Processing area temperature <150℃ (to prevent zinc from oxidizing and turning black)
When the welding heat affected zone is >300℃, apply zinc repair paint (containing 96% zinc powder)
Surface protection: Spray epoxy zinc-rich primer (80μm) within 48 hours after processing
5.What are the key considerations?
Do not hammer the zinc layer: it will cause the zinc layer to peel off and lose its corrosion resistance.
Post-treatment of thermal correction: Wipe the heating area with 10% citric acid solution to remove zinc oxide white ash
Re-spray zinc spray (such as ZRC cold galvanizing)
Test standard: Flatness ≤1mm/m²; Zinc layer damage rate <5%.