Plasma cutter how does it work

Precision plasma systems high current density are designed and engineered to produce the sharpest, highest quality cuts that are achievable with plasma.

The torch and consumable designs are more complex, and additional pieces are included to further constrict and shape the arc. A precision plasma arc is approximately K amps per square inch. Handheld Operation. When the trigger is squeezed, the power supply produces a DC current that flows through this connection, and also initiates the plasma gas flow. Once the plasma gas compressed air builds up enough pressure, the electrode and nozzle are forced apart, which causes an electrical spark that converts the air into a plasma jet.

The DC current flow then switches from electrode to nozzle, to a path between the electrode and work piece. This current and airflow continues until the trigger is released. When a start command is issued to the power supply, it generates up to VDC of open circuit voltage and initiates the preflow gas through a hose lead set to the torch.

The nozzle is temporarily connected to the positive potential of the power supply through a pilot arc circuit, and the electrode is at a negative. Next, a high frequency spark is generated from the Arc Starting Console which causes the plasma gas to become ionized and electrically conductive, resulting in a current path from electrode to nozzle, and a pilot arc of plasma is created.

The following is the same as in the previous method. That is bringing the arc into contact with the work piece. Making your choice between different cutting methods comes down to the material, its thickness and application of the parts.

The recommended upper limit of material thickness for a plasma cutting service is about 50 mm for carbon and stainless steel. Aluminium should no go past 40 mm.

Laser cutting services should be the preferred option for sheet metal and thinner plates because of its greater cutting quality and speed. Also, plasma cutting is quicker and therefore cheaper with plates starting from around 15 mm.

Then again, the question comes down to the required quality. It is, though, always possible to get a nice and smooth result with post processing. Get Instant Quote. Get instant quote. Knowledge base. Receive engineering articles to your inbox monthly. This field is for validation purposes and should be left unchanged.

Subscribe to newsletter. Table of Contents hide. I What Is Plasma? IV Choosing a Cutting Method. How plasma cutting works. Get your manufacturing quote in seconds Quote in seconds Short lead times Delivery by Fractory Get quote.

Simply put, these are computer programs that allow users to create 3D models and 2D drawings of products in the design phase. We can see it everywhere - from cars and machinery to house facades and furniture. To utilise sheet metal to its…. Let us ease your workload!

Online sheet metal fabrication gives you an instant price. Savage A TD Cutmaster ESAB Prime. You can also think of it as an electrically heated gas stream. I like to think of it as a condition where all of the electrons from every atom are flowing from atom-to-atom, instead of just orbiting. Take that stream of electricity flowing through a gas, and constrict it through a small orifice. Now that stream is really dense and moving very fast. The resulting stream can melt and blow through most metals quite easily.

Plasma cutting torches usually use a copper nozzle to constrict the gas stream with the arc flowing through it. That arc jumps from an electrode in the torch to something else — usually the conductive material being cut.

So that means that plasma cutting is only used for materials that are conductive, primarily mild steel, stainless steel, and aluminum. But lots of other metals and alloys are conductive too, such as copper, brass, titanium, monel, inconel, cast iron, etc. The problem is that the melting temperature of some of those metals makes them difficult to cut with a good quality edge. The electrode is usually made of copper, but with a metal insert at the point where the arc attaches.

Tungsten makes a great electrode material, so lots of electrodes have a tungsten insert. The problem with tungsten is that it burns up in the presence of Oxygen. So when using Oxygen or compressed air as the cut gas, the insert is made of a material called Hafnium. Hafnium lasts a lot longer in the presence of Oxygen, but it still wears a little bit with each start of the arc.

So why use Oxygen in a plasma torch? The same reason you use Oxygen in an acetylene torch — the Oxygen in the plasma stream reacts with mild steel. That chemical reaction between the Oxygen in the plasma gas and the base metal helps to speed up the cutting process and improve the edge quality.

Other specialty gases are sometimes used for other purposes. Argon gas is used when plasma marking a whole other subject. So those are some of the basics of plasma cutting — an arc carried in a stream of gas from an electrode through an orifice and then into the conductive metal that is being cut.

There are lots of other considerations that I will address later, such as swirling gases, kerf, height control, arc starting, shield gas, etc.

Posted in Cutting Systems , Tagged with Plasma. ESAB Knowledge center. What is Plasma Arc Cutting?