What is a laser machine?
The laser machine is the general name of laser equipment, including laser cutting machine, laser welding machine, laser cleaning machine, laser marking machine, laser engraving machine and so on.
According to the laser source, it can be divided into the optical fiber, co2, uv, YAG, etc.
Among them, the most widely used are optical fiber and co2.
Fiber laser is used to process metal materials, such as stainless steel, carbon steel, copper, iron, aluminium and other materials;
The co2 laser is used to process non-metallic materials, such as acrylic, plastic, cloth, MDF and other materials.
Laser machine, also called laser equipment, CNC laser machine, CNC laser equipment.
What is the working principle of the laser machine?
The laser beam is a series of very high-intensity light with a single wavelength or colour. When the beam passes through the beam path of the machine from the laser resonator that generates the beam, the diameter of the beam is only 334 inches. Before it is finally focused on the plate, It may bounce in different directions through multiple mirrors or “beam benders”. The focused laser beam passes through the nozzle hole before it hits the palate, and compressed gas, such as oxygen or nitrogen, flows through the nozzle hole.
Focusing the laser beam can be done through a special lens or curved mirror, which is performed in the laser cutting head. The beam must be precisely focused so that the shape of the focus point and the energy density of the point is completely circular and consistent, and are located in the nozzle By focusing a large beam of light to a single precise point, the heat density of that point is extremely high. Consider it like using a magnifying glass to focus the sun’s rays on a leaf and how to cause a fire. Now consider concentrating 6 kilowatts of energy to one point above, you can imagine how hot the spot will become.
The high power density causes the material to rapidly heat, melt and partially or completely vaporize. When cutting mild steel, the heat of the laser beam is enough to start the typical “oxyfuel” combustion process, and the laser cutting gas will be pure oxygen like an oxygen burner When cutting stainless steel or aluminium, the laser beam will only melt the material, and high-pressure nitrogen can blow the molten metal out of the slit.
On the CNC laser cutting machine, the laser cutting head moves on the metal plate in the shape of the required part, thereby cutting the part from the metal plate. The capacitive height control system maintains a very high temperature between the end of the nozzle and the plate being cut Precise distance. This distance is important because it determines the position of the focus relative to the surface of the sheet. The cutting quality can be affected by raising or lowering the focus from directly above, directly above or directly below the board.
There are many other parameters that also affect the cutting quality, but if all parameters are properly controlled, laser cutting will be a stable, reliable and very precise cutting process.
What is the application range of laser cutting?
Essentially, laser cutting is a manufacturing process that uses a thin focused laser beam to cut and etch materials into custom designs, patterns and shapes specified by the operator. This heat-based non-contact manufacturing process is very suitable for a variety of materials, including wood, glass, paper, metal, plastic and gems. It is also capable of producing complex parts without the need for custom-designed tools.
Laser cutting has been widely used in machinery, manufacturing, electronics, medicine, aerospace, automotive and semiconductor industries. One of the most common applications is cutting metals (whether it is tungsten, steel, aluminium, brass or nickel) Because the laser can provide neat cutting and smooth surface. The laser is also used to cut ceramics, silicon and other non-metals.
What are the advantages of laser cutting?
Laser cutting does not require changing the tool for each individual cut. The same setting is suitable for cutting many different shapes within the same material thickness range. Similarly, complex cutting will not cause any problems.
- High precision
Compared with other thermal cutting methods, high precision is one of the main advantages of laser cutting.
+- 0.1 mm accuracy provides the opportunity to achieve high accuracy without any post-processing. In most cases, such a high standard means that there is no need to increase tolerances.
+- 0.05mm ensures that the parts are very similar to each other.
Laser cutting is much faster than traditional mechanical cutting methods, especially when cutting is more complicated.
When comparing it with other thermal cutting methods such as plasma cutting or flame cutting, the laser can break them up at a certain speed until they reach a certain thickness (about 10 mm). However, the exact advantage comes down to the laser cutting machine’s Powerful features.
Since modern laser cutting machines are highly automated, this work requires almost no labour. Experienced machine operators still play an important role in the final quality, but compared to other cutting methods, the cutting speed is fast and hardly required Manual labour, so costs can be reduced.
Many machines are specially equipped with automatic loading and unloading systems.
With the correct settings, the laser cutting machine will only leave small burrs. Usually, it is not even necessary to remove it. Of course, it depends on the material, its thickness and other factors.
Another privilege is to serve as a heat-affected zone for shopping malls. As the microstructure along with the heat-affected zone changes, a smaller heat-affected zone leads to greater predictability and reliability of parts.
- Non-contact cutting
If laser cutting is performed, only the beam will come into contact with the material. Therefore, there is no mechanical friction that will wear the tool.
Large Asher cutting is suitable for many different materials. They are different metals, acrylic resins, MDF, wood, paper, etc. A machine can be configured to perform different jobs. Of course, cutting some of these materials The capacity depends on the power of your machine.
Many laser cutting machines are not suitable for cutting. Laser marking is another way to use these machines. In the production of everyday products, marking has many applications.
Finally, the technology is suitable for various profiles. Tube laser cutting can process anything from the box to the open channel.
What are the disadvantages of laser cutting?
- Need professional knowledge
As we have already said, to fully utilize the potential of a laser cutting machine, a professional operator must be available. The correct settings can ensure that the cutting quality meets the standards that people expect from technology.
- Limitation of metal thickness
Comparing laser cutting to other thermal cutting methods, it is not suitable for cutting very thick sheets. The maximum suitable thickness depends on the available machinery and knowledge at hand. On average, metal manufacturing companies tend to laser cut up to 15 or 20 mm Metal.
- Upfront costs
The price of a laser cutting machine can be as high as £1 million. The cost of a laser is twice that of a waterjet or plasma cutting machine. Although the operating costs and efficiency can be compensated for in the long run, the initial investment is still large.
- Dangerous smoke
One of the advantages of laser cutting is that it is suitable for cutting different materials. At the same time, the thermal cutting method will melt the material, thereby generating emitted gas and dangerous smoke.
This is especially true when cutting plastic. Therefore, a good ventilation system is usually expensive and a requirement for a safe working environment.
How to choose the right fiber laser?
Lasers are one of the indispensable core components in modern laser processing systems. With the development of laser processing technology, lasers are also developing, and many new types of lasers have emerged.
Early laser processing lasers were mainly high-power CO2 gas lasers and lamp-pumped solid-state YAG lasers. The growing trend was to promote laser power. However, when the laser power reached a certain requirement, the beam quality of the laser began to receive attention. The development of the company has shifted to improving the quality of the beam. Semiconductor lasers, fiber lasers and disc lasers have been developed one after another, which has made rapid development in the fields of material processing, medical treatment, aerospace, and automobile manufacturing.
CO2 lasers, Nd: YAG lasers, semiconductor lasers, disc lasers and fiber lasers are the five most common types of lasers currently on the market. What are their characteristics and application ranges?
Application: CO2 laser has a laser wavelength of 10.6um and has a low absorption coefficient for metals. It is generally suitable for cutting non-metallic materials and can be used for welding metal materials. It can be widely used in aviation, electronic instruments, machinery, automobiles and other fields Welding application.
2.Nd: YAG laser
Application: The YAG laser has a high absorption coefficient for metals and can be used for metal cutting, welding, marking and other applications. Because of its large energy, high peak power, compact structure, robustness, and reliable performance, it is widely used Industry, national defence, medical, scientific research and other fields.
- Semiconductor laser
Application: The semiconductor laser is limited by the high uniformity of the laser beam and its poor penetration, so it is not suitable for metal cutting applications, but its light spot characteristics are suitable for metal surface treatment, such as cladding, hardening, 3d printing, etc. It can be widely used in aerospace, medical, automotive and other fields.
- Disc laser
Application: The disc laser is a spatial optical path coupling structure, so the beam quality is very high. It is suitable for laser material applications such as metal cutting, welding, marking, laser cladding, hardening and 3D printing, and it is widely used in automobile manufacturing, aerospace, precision machinery, 3c electronics and other fields.
- Fiber laser
Application: Because fiber laser has high electro-optical conversion efficiency, good metal absorption coefficient, and high beam quality, it can be used for metal cutting, welding, marking, metal surface treatment and other applications. It is widely used in aerospace, automobile manufacturing, 3c electronics, medical, etc. field.
Compared with traditional co2 lasers and YAG solid-state lasers, semiconductor lasers have obvious technical advantages, such as small size, lightweight, high efficiency, low energy consumption, long life, and high absorption of semiconductor lasers by metals. With semiconductor lasers With the continuous development of technology, other solid-state lasers based on semiconductor lasers, such as fiber lasers, direct output fiber semiconductor lasers and disc lasers, have also developed rapidly. Among them, fiber lasers have developed rapidly, especially rare-earth-doped fibers. Lasers have been widely used in the fields of optical fiber communications, optical fiber sensing, and laser material processing.
How to maintain the laser?
As one of the core parts of the laser cutting machine, the importance of the laser is self-evident. We need to formulate a more detailed maintenance plan for it, and regularly maintain the equipment according to the “maintenance manual” every day, week, and month.
part 1. Daily maintenance of the laser
1) Before starting up every day, carefully check the pressure of the laser working gas and cutting auxiliary gas. If the gas pressure is not enough, it should be replaced in time.
2) Check that the cooling water pressure is maintained between 3.5~5Bar.
3) Check the temperature of the cooling water, the temperature of the water required by the selected laser is better.
4) Check the oil level of the laser vacuum pump. If it is not enough, add it. 5) Check whether the laser oil circuit, water circuit, and gas circuit are leaking and whether the vacuum pump, resonant cavity, pneumatic components, and pipe joints are leaking.
part 2. Weekly maintenance of the laser
1) Check whether there is oil or water in the gas mixing unit of the laser, and clean it if there is any; check the gas drying filter of the laser, if the colour of more than 114 becomes red or white, it needs to be replaced, and its normal colour is blue.
2) Check the filter of the chiller for impurities.
3) Check the cooling water loop for impurities.
4) Check the condensate water level in the compressed air separator (located in the air source unit). Check the vacuum pump oil level (located under the air source unit). When the pump is cold, the oil level should be at the middle line of the oil window +5mm— Between 0mm, add oil when needed.
5) Check the oil level of the Roots pump. The oil level in the gearbox of the Roots pump can be seen through the oil window on the end of the gearbox. When the pump is turned off and in a cold state, the oil level should be +5mm-0mm of the glass middle line In between, add HTCL2100 oil if necessary.
part 3. Semi-annual maintenance of the laser
1) Check whether there is any corrosion in the cooling water pipeline of the laser head of the laser.
2) Check whether the excitation power oil tank is leaking.
3) Check whether the high-voltage cable is damaged.
4) Check and clean the interior of the laser cavity and all lenses, including front window mirrors, tail mirrors, reflectors, etc.
5) After the internal lens of the laser is cleaned, the laser light output mode should be readjusted until the correct mode is reached.
6) Replace the vacuum pump oil.
7) Replace the Roots pump oil.
8) Tighten all screw plugs carefully to ensure the airtightness of the Roots pump.
9) There is a white plastic plug on the gas diversion row at the gas outlet of the Roots pump. Clean the plug, coat the inside with silicone grease. The purpose of this silicone grease is to absorb and capture physical impurities in the circulating gas of the laser. Silicone-free high vacuum grease can be used, and the coating should be very thin).
At the same time as the daily maintenance of the laser, the machine tool, air cooler, etc. must be maintained. If any parts are damaged during the use of the machine, they must be replaced in time to fundamentally ensure the normal production of the machine. , It is not only a kind of protection for the machine itself but also can ensure that the laser cutting machine always maintains an ideal cutting effect.
Precautions for laser machine operation.
- Observe the general safety operating procedures of the cutting machine. Start the laser strictly in accordance with the laser start procedure.
- Wear labour protection equipment according to the regulations, and wear protective glasses that meet the regulations near the laser beam.
- The operator must be trained, familiar with the structure and performance of the equipment, and master the relevant knowledge of the operating system.
- When the equipment is started, the operator shall not leave the post or be taken care of without authorization. If it is necessary to leave, stop or cut off the power switch.
- Do not process material before it is clear whether it can be irradiated or heated by laser to avoid the potential hazards of smoke and steam.
- Take the fire extinguisher where is easy to reach; turn off the laser when not processing; keep away from cloth, paper, or other flammable material When an abnormality is found during the processing, the machine should be shut down immediately, and the fault should be eliminated or reported to the supervisor in time.
- Keep the laser, the bed and the surrounding area clean, orderly, and free of oil, and stack the workpieces, plates, and waste materials as required.
- When using gas cylinders, avoid crushing the welding wires to avoid electric leakage accidents. The use and transportation of gas cylinders should comply with gas cylinder supervision regulations. It is forbidden to expose gas cylinders to the sun or close to heat sources.
- Observe the high-pressure safety regulations when repairing. When operating every 40 hours or weekly maintenance, every 1000 hours of operation or every six months of maintenance, follow the regulations and procedures.
- After turning on the machine, the machine should be manually started in the x and y directions at low speed, and check to confirm whether there is any abnormality.
- After inputting the new part program, you should first test run and check its operation.
- When working, pay attention to the operation of the machine tool to avoid accidents caused by the cutting machine going out of the effective stroke range or two collisions.