Fiber laser pipe cutting machines can cut thicker pipes than CO2 laser pipe cutting machines.

Fiber lasers have a shorter wavelength (around 1.06 - 1.08μm), which is more readily absorbed by metals. This allows for a higher energy density to be concentrated on the material being cut. As a result, the fiber laser can more effectively penetrate and cut through thicker metal pipes. The energy of the fiber laser can be focused more precisely, enabling it to handle greater thicknesses. For example, fiber laser pipe - cutting machines can often cut steel pipes with a thickness of up to 25 - 30 mm or more, depending on the power of the laser.

CO2 lasers have a longer wavelength (around 10.6μm), and their absorption rate by metals is lower. They tend to scatter or reflect more when dealing with thick metal surfaces. The energy density that can be effectively utilized for cutting thick metals is relatively limited. As a result, CO2 lasers are generally less efficient at cutting thick metal pipes and are more suitable for thinner materials or non - metallic materials.

Fiber laser generators can achieve high - power outputs more efficiently. Higher - power fiber lasers (e.g., 3 - 12 kW or more) can be used to cut thicker pipes. The conversion efficiency from electrical energy to laser energy is relatively high (around 30% or more), allowing for more of the input energy to be used for cutting.

CO2 lasers have a lower conversion efficiency (usually around 10 - 20%) from electrical energy to laser energy. To achieve the same cutting effect on thick pipes as a fiber laser, a much higher power input is required, and even then, the cutting efficiency may still be lower due to the aforementioned absorption and energy - density issues.