Plasma Cutting Stainless Steel - Plasma Cutting Aluminum

What materials can be cut with a CNC Plasma Machine?

Because the plasma arc needs a voltage potential between the torch and the material to be cut, the material must be conductive.  Plasma cutters can cut mild steel, stainless steel, aluminum, brass, copper and other conductive metals.

What is Plasma Cutting?

Plasma cutters use a process to cut metal using super-heated gas to cut through the metal.  This super-heated gas – called a plasma gas – is directed through a small orifice in the torch nozzle and when it hits the metal to be cut, it quickly heats it and blows it out the back of the plate.  This plasma gas is VERY hot – around 30,000 degrees F.

How does Plasma Cutting work?

A plasma power supply connected to a plasma torch is connected X-Y type table so that very precise movements and speeds can be attained.

What are my operational costs?

The operational costs of running a CNC Plasma are labor, electricity, consumables and gases.  Unlike many other forms of cutting, plasma operational costs are quite low.  Plasmas generally use compressed air or oxygen as gases, and consumable costs are quite low – with the good plasma power supplies the consumable costs are about $25 for 1200 arc starts, which may be a couple weeks of operation!

What is the difference between air and oxygen plasma?

Air plasma uses (hopefully) clean, dry compressed shop air for the plasma gas.  This has a low cost, as it is usually already available at your plant.  Oxygen plasma uses oxygen as a plasma gas.  Oxygen plasma yields a much better cut surface finish with less bevel.  For cutting mild steel, since there is an exothermic reaction with mild steel and super-heated oxygen, higher speeds can be obtained with Oxygen plasma – about 10% higher.

What is Automatic Height Control?

Often, especially with gauge material, the material will not lay perfectly flat on the table.  Automatic Height Control is a device that will raise and lower the torch automatically during the cut process in order to keep constant arc height. 

What is Ohmic Sensing?

This system uses the torch tip to accurately find the top of the plate before a cut starts

What is High-Definition plasma?

High-Definition plasma uses a power supply, torch and related components to get very clean dross-free cuts.  These plasma systems accurately set and monitor gas pressures and torch current to achieve the quality cuts.

How fast does a CNC Plasma Cutter cut?

This is dependent on material type, cut current, desired cut quality, and the plasma system type.  Thick material is around 25 inches per minute and thinner material up to 200 inches per minute.

What gases should be used for plasma cutting?

There are two different gases used in plasma cutting – the plasma gas and the shield gas.  The plasma gas is the gas that is converted into plasma and does the cutting, whereas the shield gas is used to ‘contain’ the plasma inside the plasma torch.  Sometime the same gas is used for both the plasma and shield gas.  Common plasma gases for mild steel are oxygen and air, and air is used almost exclusively for the shield gas.  Aluminum and stainless steel use either nitrogen of H35 (a mix of 35% hydrogen and 65% argon) for the plasma gas and nitrogen for the shield gas.