How Thick Can a 20kW Gantry Laser Cutting Machine Cut?

Key takeaways

• In the ideal situation, a 20kW gantry fiber laser is able to cut approximately 40-60 mm of carbon steel, 30-40 mm of stainless steel, and 25-30 mm of aluminum.
• However, the actual cutting limits are determined more by parameters other than power alone (like assist gases, grade of the materials being cut, and most importantly, the focus adjustment).
• In practice, production thicknesses are usually far less than maximum values due to the need for good cutting edges as well as fast speeds of production.
• Hence, for making a sound decision about supplier choice, it is highly recommended to do test cuts on your own material and get a clear service contract from the supplier.

How thick can a 20kW gantry laser cut?

A 20kW gantry laser cutter will be used for 40- 60 mm carbon steel and 30- 40 mm stainless steel with oxygen assist, and 25- 30 mm aluminum with nitrogen assist. These numbers represent the maximum capabilities, but normal production is typically thinner.

The range is created due to physics limitations, which are set by laser power (max), and quality decisions (practical thickness). A machine with a lower working limit than a shop expects for smooth, dross-free edges will need to establish a lower working limit.

Thickness limits by material

These are indicative sector ranges and not guarantees. Actual results will vary with grade of alloy, plate condition, and machine set-up.

If you're new to this technology, our beginner's guide to the gantry-type laser cutting machine will teach you the basics before you start making comparisons of thicknesses!

What is a gantry-type laser cutting machine?

A gantry-type laser cutting machine uses a bridge that travels across a fixed cutting table on rails, carrying the laser head along the X and Y axes. Heavy material remains stable during cutting because the sheet or plate is not moved, while the cutting head is in motion.

The design is appropriate for large sheets and thick plates and does not require compactness. Typical uses range from structural steel to heavy machine parts and large industrial parts.

The range of CNC fiber laser cutting machines from Besttechno Dynamics comes in various setups. The extra-long model is available for longer material, which provides an additional working length, but without altering the cutting principle.

What factors change maximum cutting thickness?

The thickness limits are not set for any particular wattage. The answer depends on a few factors, and here are a few to keep in mind to set your expectations accordingly.

Assist gas choice

Assisted gas can have a significant influence on the depth of cutting. Key differences include:

• Oxygen reacts with carbon steel, adding energy to the cut and helping reach greater thickness.
• Nitrogen protects the cut edge, avoiding oxide, making it appropriate for stainless steel and aluminum.
• The size of the nozzle, gas pressure, and material are all dependent on each other; otherwise, the cut quality will decrease rapidly.

Material grade and surface condition

Steel comes in different forms and has different properties. Beam energy absorption will vary due to rust, mill scale, coatings, and alloy composition. Generally, a clean, uniform plate will cut deeper and more predictably than a corroded one.

Beam quality, focus, and nozzle setup

Efficiency of the beam reaching the bottom of the plate depends on the position and alignment of the focus. The results are not great from a powerful source if the focus shifts or the nozzle wears out.

Edge quality vs maximum thickness

When the machine is strained to its breaking point, the edges are typically rough, the taper is more pronounced, and excessive dross is present on the bottom.

To understand more, read our article on understanding edge quality in fiber laser cutting, and see how fiber laser cutting eliminates dross and burr on steel plates.

Why do gantry machines suit thick plate work?

When processing thick plate cutting, the demands on the machine frame, drive system, and table are very high. A gantry design meets these requirements quite nicely, for a variety of reasons.

Rigidity and accuracy on heavy plates

Across a greater distance, the cutting head is supported by a gantry frame which deflects less than many lighter structures. This rigidity contributes to the positional accuracy in heavy plate cutting for long cutting paths. The manufacturer of a well-built Gantry Type Laser Cutting Machine in India must be able to build the frame, rails, and drive system specifically for this type of load.

Large work envelope and plate handling

The machine can accept a large and heavy plate without the workpiece having to move, as the table does not move and the bridge moves. It minimizes the handling risk and facilitates the loading and unloading using overhead cranes.

If you want to find out how to select the right laser power for metal cutting, check out the information on choosing the correct laser power for metal cutting. For comparison, we have also included a materials guide for 12kW fiber lasers available.

How should you choose a supplier?

The purchase of a high-power cutter is a long-term commitment. The right supplier will impact uptime, service responsiveness, and value derived from the machine over its lifetime.

Working with laser cutting machine manufacturers

Many businesses in Gujarat are established in the industrial fabrication sector, making many buyers prefer to buy from laser cutting machine manufacturers in Gujarat for timely access to service engineers and spare parts. When cutting plates are dependent on a machine that needs to operate smoothly, proximity is the most important factor.

Using CNC laser machine dealers for local support

Local CNC laser machine dealers in Gujarat will also provide installation, operator training, and quick on-site visits. When considering suppliers, ask them about the following before signing:

• Written warranty conditions were included for the laser source, controller, and drive parts.
• Average response time for your area.
• Availability of spares for the gas system, nozzles, and lenses.
• Use samples of your own work, rather than pictures from a brochure.

These are explained in greater detail in our guide to the selection of the proper fiber laser cutting machine supplier. Additionally, you can also learn more about Besttechno Dynamics or ask for a thick plate cutting quote.

How can you test thick plate cutting performance?

The best way to determine what a 20kW gantry machine is going to do for the material is to test it. Follow these steps:

• Take a representative sample of plates at the size that you see the most in your thickest area of the plate.
• Specify the exact alloy grade and surface condition, including any coating or rust.
• Ask for test cuts using the assist gas that you will use while producing your material.
• You should check for the straightness of edges, tapering, height of dross, and cutting speed on the provided samples.
• All results must be compared against your quality standard and not against the maximum thickness.
• You should find out the machine’s recommended working range and set production parameters a little below the maximum.

Closing line

The 20KW gantry machine has major thick plate cutting potential, with actual cut thickness being determined by inputs like materials used, cutting gas, and quality requirements being adhered to. Always test cut before settling on the expectations based on the manufacturer’s figures.

Once you decide which option to go with, get in touch with a reputed Gantry Type Laser Cutting Machine manufacturer in India. Additionally, do check the reputation of laser cutting machine suppliers in Gujarat. A little evaluation now can pay off by preventing losses later.

Frequently asked questions