1.Why is waterjet cutting the preferred method?
Key Advantages: Waterjet cutting is a purely physical cold cutting method, relying on the kinetic energy of high-pressure water (and abrasive) to erode the material. It does not generate heat.
Avoids Zinc Layer Damage: The high temperatures generated by thermal cutting methods (such as laser, plasma, and flame cutting) can ablate and vaporize the zinc layer near the cut, leading to:
Zinc layer damage: The cut edge loses its corrosion protection.
Generation of toxic zinc oxide fumes: Harmful to operator health, requiring a powerful ventilation system.
Slag buildup and recast layer: Rough cut, requiring secondary processing and cleaning.
Waterjet cutting perfectly preserves the intact zinc layer at the cut edge, with corrosion resistance unaffected.
2.How is the cutting quality of waterjet cutting?
The cut is smooth and even, without slag or burrs.
It enables high-precision cutting with small tolerances.
3.What are the suitable applications for pure water cutting?
Applications: Only suitable for very thin zinc layers or pure zinc sheets. Pure water cutting is insufficient for galvanized coils with a steel substrate.
Principle: Cuts using extremely high-pressure water jets (up to 6000 bar or more).
4.How suitable is abrasive waterjet cutting?
Applications: Used for cutting galvanized steel coils, i.e., materials with a steel substrate. This is the standard and most efficient method.
Principle: Hard abrasive particles (usually garnet sand) are mixed into a high-pressure water stream. These abrasive particles act like countless tiny blades, working together to cut the metal.
Capabilities: Can easily cut galvanized steel sheets with thicknesses ranging from a few tenths of a millimeter to over 100 millimeters.
5.What precautions should be taken during operation?
Corrosion Protection of the Cut Area (Most Important!)
Although waterjet cutting is a cold cut, it removes material, leaving the steel substrate 100% exposed at the cut. This is the most vulnerable part of the entire sheet metal and the most prone to rusting.
Post-treatment is essential: Immediately after cutting, the cut edges need rust protection. Common methods include:
Spraying with zinc-rich paint: This is the most effective and commonly used method, restoring the cut's corrosion resistance.
Using rust-preventive wax or anti-corrosion coating.
The Effect of Water on the Cut Surface
Using water during the cutting process will leave the cut area damp afterward.
Remedies: After cutting, the cut and surrounding area should be wiped or blown dry promptly to prevent flash rusting before it dries completely. Maintain good ventilation in the working environment to accelerate moisture evaporation.