Select the laser cutting machine’s power based on the thickest material you cut regularly (not based on rare, oversized workpieces): 1000W cuts carbon steel 5–10mm / stainless steel 3–5mm; 3000W cuts carbon steel 16mm (18mm with oxygen) / stainless steel 8–10mm; 6000W cuts carbon steel 20mm / stainless steel 18mm / aluminum 14mm; 12000W cuts carbon steel 30–35mm; 20000W cuts carbon steel 40mm+—purchasing power buys you maximum thickness capacity, speed, and operational headroom, not edge quality.
I. Power vs. Thickness Reference (Key Data)
1000W: Carbon steel 0.8–10mm / Stainless steel 0.8–5mm / Aluminum 0.8–3mm (Entry-level for thin sheets); 1500–2000W: Carbon steel 1–20mm / Stainless steel 1–8mm / Aluminum 1–6mm (Sufficient for standard sheet metal work); 3000W: Carbon steel 16mm (18mm with oxygen) / Stainless steel 10mm / Aluminum 6mm (Mainstream for small-to-medium factories); 6000W: Carbon steel 20mm (with oxygen) / Stainless steel 18mm / Aluminum 14mm (Workhorse for medium-to-thick plates); 12000W: Carbon steel 30–35mm (Heavy-duty work on thick plates); 20000W+: Carbon steel 40mm+ (Ultra-thick plates)—Industry consensus: choose 6kW for frequent cutting under 16mm, and 20kW for cutting under 30mm.
II. Material Differences
Carbon steel: Easiest to cut (low cost with oxygen assist);
Stainless steel: Requires more power than carbon steel (step up at least one power level for the same thickness; nitrogen cutting); Aluminum: Hardest to cut (high reflectivity makes piercing difficult; requires higher power); Copper/Brass: 1–2kW models only cut up to 2mm (high reflectivity requires special configuration); Galvanized sheet: 3000W is sufficient for thin sheets—determine power based on the primary material (step up the power level if stainless steel or aluminum is the main material).
III. Speed and Batch Size
Speed Reference: Cutting 20mm carbon steel takes approx. 1.5 min/m at 6kW and 0.8 min/m at 12kW (a twofold difference in daily output); Small Batches: 6000W is sufficient (slower speed is acceptable); Large Batches: 12000W+ (easily exceeds 100 tons/day); Edge Quality: Cutting 10mm carbon steel at 3kW results in rough edges with dross, whereas 6kW yields smoother edges—choose based on daily output (opt for high power to boost speed for large batches).
IV.
Gas Selection
Oxygen: For thick carbon steel plates (oxidation aids combustion; cut surface turns blue); Nitrogen: For stainless steel/aluminum (bright finish without oxidation; high gas cost); Air: For thin carbon steel plates (lowest cost); Higher Power: Allows for a wider range of air-cutting applications (saves money)—gas costs are a major operating expense (air cutting at 6kW+ is incredibly cheap).
V.
Selection Recommendations
First, analyze common thicknesses (the thickness range for 80% of orders); second, determine power (refer to the table above and allow for some headroom); third, calculate daily output (choose 12000W+ for large batches); fourth, select bed size (3015/4015/6m large beds based on workpiece dimensions); fifth, verify via test cuts (use actual material to check speed and edge quality)—Laser cutter power: start at 3kW for thin sheets, 6kW for up to 16mm, and 20kW for up to 30mm;
analyze thickness → select power → test cut → place order.
