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Technologies
WHAT IS IL PLASMA
PLASMA CUTTING
What is plasma ?
Plasma was discovered by chance in 1879 following a series of experiments conducted by Sir William Crookes. The new chemical element, which had the property of emitting a green beam in the electromagnetic spectrum, was named Thallium, from the Greek Thallos (green shoot). Cathode-ray tubes and neon lights were subsequently developed based on this discovery. We see natural phenomena associated with Plasma in the shape of the northern and southern lights, lightning and the sun, the stars and nubulae.
The first practical application of Plasma cutting was made in 1955 thanks to Robert Gage, the patent holder and Union Carbide employee. The application, already known as plasma transfer in welding applications, was modified by using a nozzle that could channel the Plasma flux.
The term Plasma is used to identify an ionized gas comprising a series of electrons and ions whose electrical charge is zero. In the case of the application of Plasma cutting, the ionized gas is the cutting gas (Air, Oxygen, Nitrogen), which changes depending on the type of generator used and depending on the process due to be adopted. In this case, Plasma forms as a result of the gas passing through an electrical arc, which provides the force required to form electrons and ions. Plasma as such is called the fourth state of matter, the first state being the Solid phase, the second the Liquid phase and the third the Gas phase. The fourth state, namely the Plasma phase, is a state in which the electrons or part of them have been removed from the atoms making up the Gas that they come from. These electrical charges, mainly made up of electrons and ions, are by their very nature great conductors of electrical energy and hence capable of producing large magnetic fields. These magnetic fields can cause interference or damage to the electrical components that make up the machinery on which the Plasma generator is installed. Consequently, all the cutting machine's component equipment must be suitably shielded and, whatever the case, the system's earth must have as low an impedance as possible, and should certainly not exceed 20 ohms (5 ohms recommended). As a result, users of said systems are required to exercise special care when earthing the electrical system to which both the Plasma generator and cutting machine will be connected. It is not unusual to encounter problems, especially with the electric motors' encoders. The critical stage is when the Plasma arc is initiated with voltages usually ranging from 8,000 to 10,000 volts.
Plasma can form on the surface of a vehicle going through a gas at high speed, like a spacecraft re-entering the atmosphere. Plasma technology as we know it today stems from research into said phenomena.
In the practical application of cutting, Plasma forms out of a Gas called the Plasma Gas, which goes through a high-intensity magnetic field. The Plasma or Plasma jet is thus directed through the flow generated by the gas stream. The magnetic field that forms as a result of the electrical discharge of the electrode (which is housed inside the Plasma torch, negatively charged) and the material (positively charged), which has to be conductive to allow the arc to strike, causes the ionizing Plasma effect in the gas. This highly exothermic reaction produces enough heat to melt any material. The temperature reached as a result of the Plasma effect ranges from 22,000 to 25,000 degrees Centigrade depending on the Plasma gas used. The directing of this energy, which is suitably channelled through the Plasma cutting torch, is what makes it possible to cut sheet metal.
Plasma was discovered by chance in 1879 following a series of experiments conducted by Sir William Crookes. The new chemical element, which had the property of emitting a green beam in the electromagnetic spectrum, was named Thallium, from the Greek Thallos (green shoot). Cathode-ray tubes and neon lights were subsequently developed based on this discovery. We see natural phenomena associated with Plasma in the shape of the northern and southern lights, lightning and the sun, the stars and nubulae.
The first practical application of Plasma cutting was made in 1955 thanks to Robert Gage, the patent holder and Union Carbide employee. The application, already known as plasma transfer in welding applications, was modified by using a nozzle that could channel the Plasma flux.
The term Plasma is used to identify an ionized gas comprising a series of electrons and ions whose electrical charge is zero. In the case of the application of Plasma cutting, the ionized gas is the cutting gas (Air, Oxygen, Nitrogen), which changes depending on the type of generator used and depending on the process due to be adopted. In this case, Plasma forms as a result of the gas passing through an electrical arc, which provides the force required to form electrons and ions. Plasma as such is called the fourth state of matter, the first state being the Solid phase, the second the Liquid phase and the third the Gas phase. The fourth state, namely the Plasma phase, is a state in which the electrons or part of them have been removed from the atoms making up the Gas that they come from. These electrical charges, mainly made up of electrons and ions, are by their very nature great conductors of electrical energy and hence capable of producing large magnetic fields. These magnetic fields can cause interference or damage to the electrical components that make up the machinery on which the Plasma generator is installed. Consequently, all the cutting machine's component equipment must be suitably shielded and, whatever the case, the system's earth must have as low an impedance as possible, and should certainly not exceed 20 ohms (5 ohms recommended). As a result, users of said systems are required to exercise special care when earthing the electrical system to which both the Plasma generator and cutting machine will be connected. It is not unusual to encounter problems, especially with the electric motors' encoders. The critical stage is when the Plasma arc is initiated with voltages usually ranging from 8,000 to 10,000 volts.
Plasma can form on the surface of a vehicle going through a gas at high speed, like a spacecraft re-entering the atmosphere. Plasma technology as we know it today stems from research into said phenomena.
In the practical application of cutting, Plasma forms out of a Gas called the Plasma Gas, which goes through a high-intensity magnetic field. The Plasma or Plasma jet is thus directed through the flow generated by the gas stream. The magnetic field that forms as a result of the electrical discharge of the electrode (which is housed inside the Plasma torch, negatively charged) and the material (positively charged), which has to be conductive to allow the arc to strike, causes the ionizing Plasma effect in the gas. This highly exothermic reaction produces enough heat to melt any material. The temperature reached as a result of the Plasma effect ranges from 22,000 to 25,000 degrees Centigrade depending on the Plasma gas used. The directing of this energy, which is suitably channelled through the Plasma cutting torch, is what makes it possible to cut sheet metal.