How does a Plasma Cutter Work

What is a Plasma Cutter

Plasma cutters need gas, which is compressed air that enters the torch and is then distributed by the gas chamber in two ways, forming the plasma gas as well as the auxiliary gas.

Plasma Cutting Machine is a machine that processes metal materials with the help of plasma cutting technology.

Plasma cutting is a processing method that uses the heat of a high-temperature plasma arc to partially or partially melt (and evaporate) the metal at the workpiece kerf, and uses the momentum of the high-speed plasma to remove the molten metal to form the kerf.

Working principle

1. Plasma cutting machine plasma is heated to a very high temperature in the highly ionized gas, in the transfer of it from the arc power to the workpiece, the high heat makes the workpiece melted and blown off, the formation of the plasma arc cutting work.
2. The principle of plasma is to change from state to liquid (water), then heated to form a plasma, plasma with a negative charge in the proximity is also the fourth state of material existence.
3. It is possible to cut and weld metal by a very large current line and very high temperature. The temperature and running speed of the plasma will blow away the molten metal to achieve the purpose of cutting.

What is needed for a Plasma Cutter

Plasma cutting requires compressed air.
Fine plasma has a variety of gases such as oxygen, nitrogen and hydrogen to blow away the molten metal fluid for cutting purposes. Argon is used as a shielding gas for argon arc welding.

Features

1. Automatic and semi-automatic cutting dual mode selection
2. Digital precise control of cutting length
3. Easy to operate

Plasma Cutter Work

Preparation for use

1. should check and confirm that the power supply, gas source, water source without leakage of electricity, gas, water, grounding or zeroing safe and reliable.
2. Trolley, workpiece should be placed in the appropriate position, and should make the workpiece and cutting circuit positive connection, cutting work surface should be equipped with a slag pit.
3. The nozzle aperture should be selected according to the workpiece material, type and thickness, adjust the cutting power, gas flow and electrode shrinkage.
4. The automatic cutting trolley should be run by the empty car, and selected cutting speed.
5. Operators must wear protective masks, welding gloves, hats, filter film dust masks and soundproof earmuffs. Do not wear protective goggles personnel are strictly prohibited from directly observing the plasma arc, the bare skin is strictly prohibited close to the plasma arc.
   When cutting
6. When cutting, the operator should stand at the upwind to operate. Can draw air from the lower part of the table, and it is desirable to reduce the open area of the operating table.
7. When cutting, when the no-load voltage is too high, the electrical grounding, zeroing and torch handle insulation should be checked, the table should be insulated from the ground, or in the electrical control system installed no-load circuit breaker.
8. High-frequency generator should be equipped with shielding shield, with high-frequency arcing, should immediately cut off the high-frequency circuit.

Cutting operations and with the protection of personnel

1. Site use of plasma cutting machine, should be equipped with rain, moisture, sun protection machine shed, and should be equipped with the appropriate fire-fighting equipment.
2. When cutting at height, you must fasten the safety belt, cut around and below the cutting fire prevention measures should be taken, and should be supervised by a person.
3. When the need to cut pressurized containers, sealed containers, oil barrels, pipelines, stained with combustible gases and solutions of the workpiece, should first eliminate the pressure in the container and pipeline, eliminate combustible gases and solutions, and then flush toxic, hazardous, flammable substances; residual grease container, should first be flushed with steam, alkaline water, and open the cover, to confirm that the container is clean, and then filled with water before cutting. Welding and cutting in the container should be taken to prevent electrocution, poisoning and asphyxiation measures. Cut sealed containers should be left out of the air holes, if necessary, at the inlet and outlet equipment ventilation equipment; lighting voltage in the container shall not exceed 12 V, welders and workpiece should be insulated between; outside the container should be set up to monitor. It is strictly forbidden to cut in the container that has been painted and plastic.
4. Pressure vessels and pipelines, electrically charged equipment, bearing structure of the stress parts and containers with flammable and explosive substances are strictly prohibited to cut.
5. No welding and cutting in the open on rainy days. When working in wet areas, the operator should stand in a place where insulated items are laid, and should wear insulated shoes.
6. After the operation, the power should be cut off and the gas source and water source should be shut off.

Operation procedure

Manual non-contact cutting

(1) The torch roller touches the workpiece, and the distance between the nozzle and the workpiece plane is adjusted to 3~5mm. (The “cut thickness selection” switch is set to high grade when the main machine is cutting).
(2) turn on the torch switch, ignite the plasma arc, cut through the workpiece, moving to the cutting direction at an even speed, the cutting speed is: to cut through the premise, should be fast rather than slow. Too slow will affect the quality of the incision, and even break the arc.
(3) cutting is completed, close the torch switch, the plasma arc extinguished, at this time, the compressed air delayed spray to cool the torch. After a few seconds, the spraying will stop automatically. Remove the torch to complete the whole cutting process.

Manual contact cutting

(1) The “cut thickness selection” switch is set to low gear, which is used when cutting thin boards by single machine.
(2) Place the torch nozzle at the starting point of the workpiece to be cut, turn on the torch switch, ignite the plasma arc and cut through the workpiece, and then move at an even speed along the cutting direction.
(3) After cutting, open and close the torch switch, at this time, the compressed air is still spraying out, after a few seconds, the automatic stop spraying. Remove the torch to complete the whole cutting process.

Automatic cutting

(1) Automatic cutting is mainly suitable for cutting thicker workpieces. Selected “cut thickness selection” switch position.
(2) remove the torch roller, the torch and semi-automatic cutting machine coupling solid, random accessories available in the coupling.
(3) connected to the semi-automatic cutting machine power supply, according to the shape of the workpiece, install a good guide or radius bar (for linear cutting with guide, if cutting round or arc, you should choose the radius bar).
(4) If the torch switch plug set off, replace the remote control switch plug (available in the random accessories).
(5) According to the thickness of the workpiece, adjust the appropriate travel speed. And the “reverse” and “down” switch on the semi-automatic cutting machine to the cutting direction.
(6) Adjust the distance between the nozzle and the workpiece to 3-8mm, and adjust the nozzle center position to the start of the workpiece cutting slit on the strip.
(7) turn on the remote control switch, cut through the workpiece, turn on the semi-automatic cutting machine power switch, you can cut. In the initial stage of cutting, you should always pay attention to the cutting seam and adjust to the appropriate cutting speed. And always pay attention to whether the two machines work properly.
(8) cutting is complete, close the remote control switch and semi-automatic cutting machine power switch. So far, the completion of the whole process of cutting.

Manual cutting round

According to the material and thickness of the workpiece, select the single or parallel cutting method, and select the corresponding cutting method, the random accessories in the crossbar tightened in the torch cage screw hole, if a length is not enough, can be connected one by one to the required radius length and tighten, then, according to the radius length of the workpiece, adjust the distance between the top to the torch nozzle (must take into account the factors of the width of the cut). After adjustment, tighten the top fastening screw to prevent loosening, and relax the cage fastening knurled screw. At this point, the workpiece can be cut round work.