What cutting speed should I expect per thickness on a fiber laser?

Updated:

Short answer

Speed falls sharply with thickness and depends on the gas: a 6 kW fiber cuts 1 mm stainless with nitrogen at 30–40 m/min, 6 mm at around 5 m/min, and 10 mm at 2–3 m/min. Mild steel with oxygen is slower on thin sheet but keeps cutting into 20 mm plate where nitrogen becomes impractical.

Why your machine is slower than the datasheet

Symptom Likely cause First action
Small parts and many corners; the head never reaches programmed feed. Geometry, not the laser Judge productivity by parts per hour on a real nest, not by maximum linear speed.
Long straight cuts hit target speed, everything else does not. Acceleration limits Compare machines on acceleration as well as top speed; it dominates on typical fabrication nests.
The same program runs slower reliably as the week goes on. Consumable condition Track nozzle and protective glass life; degraded consumables force operators to reduce feed.
Bottom edge roughness
Bottom edge roughness

Typical cutting speed, m/min

Material and gas1 mm3 mm6 mm10 mm20 mm
Stainless, nitrogen, 3 kW20–255–71.8–2.40.7–1.0
Stainless, nitrogen, 6 kW30–4010–144.5–62–2.8
Mild steel, oxygen, 3 kW7–93.5–4.52.4–31.6–2.00.7–0.9
Mild steel, oxygen, 6 kW9–114.5–63–42.2–2.81.0–1.3

Shop speeds sit below datasheet maxima: acceleration, part geometry, nesting and sheet quality all take their share.

Related questions

Does doubling the power double the speed?
No. On thin sheet, gains are large; on thick plate the limit shifts to melt removal and gas dynamics, so doubling power gives far less than double the speed.
Is cutting faster always cheaper?
Not when it costs edge quality that needs deburring, or when gas consumption rises. Cost per part includes assist gas, consumables and rework, not just machine minutes.

Next questions operators ask

Ranges are given for a typical 3–6 kW fiber machine with a clean beam path. Always verify against your machine manufacturer’s table before production.

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