Plasma Cutting Machine

Following Companies Manufacturing Cutting Machines Machine (40 Companies)

1. Using air cylinders or nitrogen gas
2. Using air compressors

1. Plasma cutting speed is on average three or four times that of acetylene cutting (especially for cutting thin metal sheets up to 4 mm). As the thickness becomes less than 4 mm, the cutting speed increases almost exponentially.
2. Unlike acetylene cutting process in which if we do not preheat the piece or sheet, deformation will occur in that sheet or piece, there is no need for preheating in the process of plasma cutting because the plasma works in a thin line.
3. By plasma cutting you will be able to cut all ferrous and non-ferrous metals, while through acetylene cutting you will only be able to cut ferrous metals.
4. Plasma cutting accuracy is higher than that of acetylene cutting. Plasma cutting is more efficient than acetylene cutting, especially in making precise and relatively small holes.
5. By plasma cutting, you are able to chamfer relatively thick sheets, while by acetylene cutting, this is almost impossible.

1. Advantages of Plasma Cutting Machine

• It is capable of cutting all conductive materials, especially relatively thick metals

• Excellent cutting quality for thicknesses up to 50 mm

• The best way to cut stainless steel and aluminum to medium thickness

• It has the ability to be automated

• Metal loss and seam cuts are less than oxygen cutting

• Cutting speed is faster than oxyacetylene cutting

• All kinds of curves and hard shapes and cross-sections are created accurately

• It has a lower cutting cost than oxygen cutting

• Longer life of plasma equipment than other flame cutters

• Inert gas is used during cutting by plasma, which makes the process safer

2. Disadvantages of plasma cutting machines

• It is larger than HAZ laser cutting.

• In cutting thin sheets, it has a lower quality than laser cutting.

• It has less accuracy than laser cutting.

• Thickness (cutting seam) larger than laser cutting.

• Restrictions on cutting thick metals according to their material.

• Plasma cutting is noisy and produces excess and dangerous vapors.

• The cost of replacing and repairing its parts is high.

• Due to the overheating, we will see an increase in hardness in the cutting area.

1. Make the device settings such as the level of amps and air pressure exactly according to the vendor's catalog or based on the label on the case of the machine.
2. Make sure that the consumable parts of the torch are impeccable. Any fault in any of them (electrode, cap, flame spreader, etc.) can greatly affect the quality of the cut.
3. According to the device settings, especially the amp setting, use the appropriate torch head. The narrower the torch head, the smaller the width of the arc and the slightly longer its length, which makes the cuts more accurate and of better quality. It is worth noting that this is more practical for cutting relatively thin sheets.
4. If you want to have a straight or circular cut, use auxiliary equipment.
5. Before starting the cutting operation, and in case the shape of the cut has asymmetric mazes, it is better to go through that path once or twice without turning on the torch.
6. As the speed of advance of the torch is very important and low speed of progress causes the margins of the sheet to be damaged or melted, it is better to make a cut on a waste sheet (with the same thickness and the same material) once prior to the actual cutting process.
7. Use the spacer ring for long cuts. This device ensures the standard distance between the electrode and the sheet and creates the best electric arc. In addition, using the spacer ring makes the life of the consumable parts of the torch longer.
8. Do not use the torch to remove slag, because hitting the tip of the torch will greatly reduce the life of consumable parts.
9. When you want to cut the sheet, use your free hand to lean on and to guide the hand that controls the torch. This prevents vibration and the cutting edges will be of better quality.
10. After finishing the cutting operation, open the torch and thoroughly clean the torch parts. If any of the consumable parts of the torch is worn or damaged, replace it with a new one. Then open the moisture absorber filter on the back of the device and replace it if it needs to be replaced. As you know, if moisture enters the device along with gas or if the filter cannot work efficiently, you will not have a quality cut, and it will also have a great impact on the premature wear of consumable parts.
11. If you want to cut stainless steel sheets accurately and with high quality, it is recommended to use nitrogen gas instead of air. This is also true for laser cutting machines. Nitrogen is drier than air and is also less oxidized.

1. Manual plasma cutting machines
2. Portable plasma cutting machines
3. CNC plasma cutting machines

1. Manual plasma machines

These machines consist of three main parts, namely the torch, the generator, and the connecting cables. In this type of cutting process, the speed of the torch and its movement is guided and controlled by an operator. This type of machines are mostly used for workshops that do less serial work, or have long cutting processes or slightly geometrical cuts.




Miller Company: A manufacturer of plasma cutting machines in Germany

The company has managed to market a type of plasma cutting machine called Auto-line that can cover a voltage range from 190 to 630 volts. In simple terms, whether you have single-phase or three-phase electricity, or the current is 50 Hz or 60 Hz makes no difference for this type of machine.

Thanks to this special technology, increasing or decreasing the voltage will not have an effect on creating an electric arc, and there will be a uniform arc in the cutting process. If there is oscillation of the electric current in your workshop, it is recommended that you use Auto-line, because the instability of the electric current will damage plasma cutting machines and will have a negative effect on the cutting quality.

The environment of many factories and workshops is relatively polluted. This pollution includes particulate matter, which can be metal chips, dust mites and fine burrs. Due to the fact that the structure of plasma cutting machines is electrical, and that electronic components must be kept cool during operation, these pollutants enter the case by the suction of the fan on the back of the machine, settle on the electronic components, and play an insulating role for those components, which will greatly reduce the life of the machine. By installing a special tunnel system called wind tunnel technology, Miller Company has been able to direct the air that is drawn into the case in such a way so that pollutants do not sit on sensitive electronic components such as diodes, capacitors and transistors, and the air has only a cooling role.








2. Portable plasma cutting machines

If we want to cut a relatively large number of sheets with the same specifications and design on a daily basis, it will no longer be cost-effective to use a manual plasma cutting machine. In this case, to create quality cuts and save time, it is smart to use a portable plasma cutting machine. The important advantages of this type of device are as follows:

• Ability to cut geometric, non-geometric, and straight shapes with high quality
• Faster cutting speed compared with manual plasma cutting machines
• Reduction of human errors during cutting
• Cost-effectiveness
• Occupying less space compared with desktop plasma cutting machines
• CNC plasma cutting machines






3. CNC plasma cutting machines

CNC plasma cutting machines are divided into different types, each of which has suction applications according to the production needs and the shape of the workpiece. Also, various forms of CNC plasma cutting machines are derived from the type of part or parts that are specially designed and manufactured. In the following articles, we will review examples of table and gate plasma cutting machines, and CNC profile and pipe cutting machines.

1. Advantages of CNC Plasma Cutting Machine

• Excellent versatility in cutting a variety of sheets and relatively thin and thick metal thickness

• Precise adjustment, high speed, and reduced production costs

• Suitable for cutting all kinds of metals, especially carbon steels, stainless steels, aluminum, copper, and brass

• Good productivity and performance in creating a variety of relatively complex and artistic shapes

• Cutting accuracy due to the use of a numerical control system

• Ability to store a variety of production programs for ease and reduce production time

• The results obtained using a CNC plasma cutting machine are much better than the size of the cutting processes. If properly adjusted and programmed, it leaves no debris and chips.

• Another benefit is increased safety due to automation. Because all the process and equipment is done automatically, the risks of cutting are reduced.

• It is easy to use and train and reduces the cost of hiring a specialist operator




2. Disadvantages of CNC plasma cutting machine

• Plasma cutting is typically suitable for thicknesses up to 20 mm

• Noise is generated when cutting thick plates

• If the thickness of the piece is more than 20 mm, the cross-sectional area tends to be V-shaped.

• The purchase cost is higher than other plasma cutting machines

1. What material do you want to cut?
2. What is the size and shape of your material and part?
3. What is the amount of cutting in each work shift or per hour?
4. What should be the desired cutting accuracy?
5. Do you want to automate the cutting process?
6. Do you have any restrictions on budgeting for the cutting machine?

• Torch
• The device
• Connecting cables

1. Contact torches:

As a well-known fact, there are two electric poles (positive and negative) in welding and cutting processes. Normally, for welding and cutting, one pole is attached to the workpiece and the other to the torch. In direct contact torches, whenever the torch is brought close to the workpiece or the sheet (which is connected to a negative pole), an electrical discharge occurs, which can bring about the welding or cutting depending on the type of machine. These types of torches are called direct plasma contact torches. The structure of this type of torches is simpler than that of non-contact torches and their consumable parts are cheaper than those of indirect torches. One of the disadvantages of this type of torch is that if the workpiece or sheet has impurities such as rust, oil, or paint, the cutting will not take place or the cutting quality will be poor. This is because there is an interface between the two connections. These types of torches are also known as high frequency torches.








2. Non-contact torches:

These types of torches are structurally different from contact torches because an extra wire (negative pole) is inserted into the torch and the initial combustion takes place within the torch. This type of torch is equipped with a trigger and whenever the trigger is pulled, electricity is discharged. Therefore, there is no longer a need to bring the torch close to the piece or sheet in order to light the torch. One of the important advantages of this type of torches is that in the process of cutting painted, rusty, or oily parts, the cutting process is done easily. Of course, another advantage of this type of torch is that it can be mounted on other devices such as robots and CNC machines, because this type of torch can start cutting or turning off by receiving command from PLC. Non-contact torches act like spark plugs inside a car cylinder. Upon starting these torches, an electrical discharge is created inside the cylinder filled with compressed gas. These types of torches are also known as pilot torches.