What is laser?
A laser is a type of light that, like other light-emitting entities in nature, is generated through the transition of atoms, molecules, or ions via spontaneous emission.
However, lasers differ significantly from ordinary light as they rely only on spontaneous emission for a very brief period at first, and their subsequent processes are entirely determined by laser radiation.
This unique characteristic of lasers results in their pure color, almost no divergence directivity, and extremely high luminous intensity.
Characteristics of 3D fiber laser cutting robot
1. Main characteristics of fiber laser
(1) The fiber laser has a high electric-optical conversion efficiency, with a conversion efficiency of over 25%. Additionally, low-power fiber lasers do not require a water cooler and can use air cooling to save power consumption during operation, reduce operation costs, and achieve maximum production efficiency.
(2) The laser only needs electric energy to operate, without requiring the generation of additional laser gas. This results in the lowest possible operation and maintenance costs.
(3) The fiber laser employs a semiconductor modular and redundant design. There are no optical lenses in the resonant cavity, and it does not require start-up time. These advantages include no adjustment, maintenance, high stability, and reduced accessory and maintenance costs, which are unmatched by traditional lasers.
(4) The fiber laser has an output wavelength of 1.06 μm, which is one-tenth the wavelength of CO2. With high precision, excellent output beam quality, and high power density, it is highly effective for metal material absorption. The fiber laser also offers excellent cutting and welding capabilities, thus minimizing processing costs.
(5) The entire machine’s optical path is through fiber transmission, eliminating the need for complex light guide systems such as reflectors. The optical path is simple and stable, with a maintenance-free external optical path.
(6) The cutting head includes protective lenses, resulting in minimal consumption of valuable consumables such as reflectors and focusing lenses.
(7) Light is exported through the optical fiber, making the mechanical system’s design simple and easy to integrate with robots or multi-dimensional workbenches.
(8) By adding a shutter, the laser can be divided into multiple machines with one device. Through optical fiber splitting, it can be divided into multiple channels and work simultaneously. This feature allows for easy function expansion and convenient and straightforward upgrades.
(9) The fiber laser is small in size, light in weight, movable in working position, and has a small floor area.
2. The biggest feature of 3D laser cutting is high flexibility
Three-dimensional laser cutting is especially suitable for cutting small quantities of sheet metal materials that have a three-dimensional structure.
The high flexibility of this cutting method is evident in two aspects:
(1) The laser cutting machine can adapt to different types of materials and can cut any plate using a numerical control program.
(2) The processing path is determined by the program, and modifications can be made easily if the processing object changes. This is particularly useful for trimming and hole cutting of parts.
Compared to trimming and punching dies, which are unable to process different parts and are expensive to produce, three-dimensional laser cutting has become an increasingly popular alternative.
Although the fixture design and use of three-dimensional machining can be complex, laser processing does not add any machining force to the plate being processed, making fixture manufacturing relatively simple.
Moreover, by equipping a laser device with different hardware and software, a variety of functions can be achieved.
3. Advantages and disadvantages of robot + fiber laser combination
(1) By replacing the five-axis machine tool with an industrial robot, which can describe the spatial trajectory and achieve three-dimensional cutting, the accuracy requirements of the automotive sheet metal panel and chassis parts industry can still be fully met, despite the industrial robot having slightly lower repeated positioning accuracy of about ±100 μm compared to the five-axis machine tool.
The use of industrial robots significantly reduces the cost of the system, including the power consumption system costs, system operation and maintenance costs, and floor area of the system.
(2) Replacing CO2 with fiber laser technology has become popular due to its rapid development in recent years. Compared to traditional lasers, fiber laser technology offers better cutting quality, longer service life, lower maintenance costs, lower power consumption, and lower system cost.
A key advantage of fiber laser technology is that the laser can be transmitted through the fiber, which makes it easy to connect with the industrial robot and achieve flexible processing.
(3) The combination of industrial robot and fiber laser technology is ideal for processing and can complete processes such as trimming and cleaning in a single operation. The neat incision achieved eliminates the need for subsequent process reprocessing, significantly shortening the process flow, reducing labor and mold costs, and improving the product grade and added value.
The company’s offline programming software is selected to generate the cutting track through digital simulation, which eliminates the need for complicated manual teaching and is more suitable for personalized cutting needs, such as small batch and multi-batch maintenance market, new product trial production, and non-standard customization.
Investing in highly flexible and efficient laser cutting equipment to replace expensive stamping equipment and cutting equipment can allow for more flexible product changes and better market opportunities.
(4) The perfect integration of cutting-edge fiber laser technology and digital control technology represents the most advanced level of laser cutting.
The professional laser cutting machine control system and computer operation can ensure cutting quality, make the cutting work more convenient, and the operation simpler.
Equipped with an intelligent manipulator, it can realize three-dimensional cutting with convenient operation and a high degree of intelligence, ensuring high speed, high precision, and high reliability of the equipment.
The laser cutting head is equipped with an imported laser cutting head that is sensitive and accurate, and can effectively cooperate with the manipulator to avoid collision between the cutting head and the processed plate, ensuring cutting focus position and cutting quality stability.
The laser cutting head can withstand 1.0MPa gas pressure, and the high-pressure gas circuit equipment improves cutting ability on stainless steel and other difficult cutting materials.
(5) The only limitation of the system is that it can only process metal workpieces, not non-metallic ones.
Introduction of 3D fiber laser cutting machine technology
The 3D fiber laser cutting machine is an advanced laser cutting equipment that is composed of a special fiber laser cutting head, a high-precision capacitive tracking system, a fiber laser, and an industrial robot system. It can perform multi-angle and multi-directional flexible cutting of metal plates with different thicknesses.
Related reading: 3D Laser Cutting Machines: Exploring the Latest Trends and Future
Three-dimensional laser cutting utilizes the flexible and fast action performance of industrial robots. Depending on the size of the workpiece being cut and processed by users, the robot can be installed in front or reverse to teach programming or offline programming for different products and different tracks.
The sixth axis of the robot is equipped with a fiber laser cutting head to cut irregular workpieces in three dimensions. The optical fiber laser cutting head is equipped with a follow-up device and an optical path transmission device. The laser is transmitted to the cutting head through the optical fiber, and then the focusing system is used to focus. Multiple sets of focusing systems are developed for plates of different thickness to cut a variety of three-dimensional metal plates in multiple directions, meeting the needs of customers.
The power of the selected fiber laser varies according to the thickness of the metal plate. The power of the fiber laser for three-dimensional cutting is generally divided into 200W, 300W, 400W, 500W, 1000W, and other specifications. Lasers with different power are equipped with cooling systems with different refrigerating capacities to ensure their normal operation.
Additionally, the appropriate length of operating optical fiber transmission laser should be selected according to the working radius of the manipulator and the size of the workpiece processed by the customer to meet their cutting requirements.
The auxiliary gas used in the three-dimensional fiber laser cutting machine is 99.99% oxygen, which significantly improves the cutting accuracy, speed, and section effect.
The factors that generally affect the cutting quality of a three-dimensional fiber laser cutting machine are:
- Laser power
- Size and purity of the auxiliary gas
- Focal length of the cutting head
- Thickness of the processed workpiece
- Teaching trajectory of the robot or the digital-analog positioning accuracy of offline programming
- Path repetition accuracy, repetition positioning accuracy, and speed of the robot.
Six technical advantages of 3D cutting system
(1) The cutting speed is fast, twice that of similar products. The typical parameters for this product include a 200W laser for 0.8mm thick carbon steel, with a linear cutting speed that can reach 10m/raino.
(2) The cutting accuracy is high, with a repeated positioning accuracy of the system as high as ±100 μm, which fully meets the needs of the automotive sheet metal panel industry.
(3) This product can cut small circles with a diameter as small as 2mm. The cutting effect is smooth and beautiful, with no visible deformation or burr. The cutting time of a single small circle can be controlled within 2 seconds.
(4) With a manipulator that has an arm length of 2m, this product can achieve 3m × 2-D plane cutting of 1.5m in addition to the hemispherical three-dimensional processing area with a diameter of 3m. It can realize the combination of two and three-dimensional cutting, cut the material on the standard blank, and combined with the company’s free distribution two-dimensional software that has nesting and path optimization functions, it is a great investment for those in the sheet metal industry.
(5) The offline programming software can be selected according to the actual needs, which can read the digital analog of UG, SOLIDWORK, and other three-dimensional mapping software export formats and directly generate the cutting track after modification, instead of manual teaching. It is simple and easy to use.
(6) This product has an industrial control concept, modular design, high protection level of the whole system, high protection level of the manipulator, high system integration, few faults, anti-shock vibration, anti-dust, no optical adjustment or maintenance, and is truly suitable for the field of industrial processing.
Application of 3D fiber laser cutting robot
1. Application of 3D laser cutting industry
Three-dimensional laser cutting is widely used in various industries such as sheet metal processing, metal fabrication, advertising production, kitchenware, automotive, lighting, saw blades, elevators, metal crafts, textile machinery, grain machinery, eyewear production, aerospace, medical devices, instruments, and meters.
In particular, the sheet metal processing industry has widely adopted this technology and replaced traditional processing methods due to its efficiency and accuracy, making it a popular choice among industry users.
2. Machinable materials
Cutting of stainless steel, carbon steel, alloy steel, silicon steel, spring steel, aluminum, aluminum alloy, galvanized plate, aluminized zinc plate, pickled plate, copper, silver, gold, titanium and other metal plates and pipes.
3. Three dimensional laser cutting machine processing high-strength steel
Trimming high strength steel poses a significant challenge.
A three-dimensional laser cutting machine is the most suitable tool for cutting the edges of formed sheet metal parts, particularly for steel plates with a strength of up to 1500MPa since there are no alternative processing methods available.
Traditional equipment’s stamping dies or cutters’ service life is significantly reduced when processing these high hardness materials. However, laser cutting does not encounter such issues.
Furthermore, it has the added benefits of a short installation time and flexible product replacement or sample production.
4. Three dimensional laser cutting machine is applied to the cutting of automobile side wall
(1) The B-side wall, made of high-strength steel, is hot-formed to achieve high hardness and withstand great stress. This enhances the impact resistance and safety of the car, and justifies why automobile manufacturers opt for high-strength steel despite its high cost.
(2) Laser cutting is utilized for drilling automobile bumper equipment due to the complexity and unique shape of the part. Traditional stamping methods result in parts with deformation and stress. However, with laser cutting, there is no need for a complex fixture system, and the process is stress-free, deformation-free, burr-free, and collapse-free. This makes it more convenient for later processing and installation.
In the field of automobile manufacturing, laser technology enables high-precision, high-quality, flexible, and intelligent production, while improving the safety, cleanliness, and cost-effectiveness of car manufacturing. Ultimately, this leads to concessions for ordinary consumers. Science and technology make life beautiful, and laser technology enhances the beauty of cars.
Development trend of 3D laser processing technology
1. High precision, high speed and high flexibility
Although laser cutting is limited by the “thermal (optical) processing” method, its accuracy still lags behind other NC processing methods such as NC milling. However, this does not affect its application, as the accuracy can be improved by enhancing equipment performance and selecting appropriate process parameters.
Regarding speed, laser cutting can reach several meters or even more than ten meters per minute, but it is not as efficient as metal stamping dies in mass production. To improve production efficiency, we need to enhance the machining speed of the machine tool.
However, during actual normal speed movement, if the speed is too high, it results in a significant inertial force when realizing acceleration, deceleration, and changing the mode of motion. To achieve high speed and reduce the inertial force, we must reduce the mass of the moving part.
2. Low cost
The primary reason for the high cost of laser equipment is the expensive nature of the lasers themselves.
Currently, domestically self-developed lasers struggle to reach the necessary optical mode for effective three-dimensional cutting. This limits their competency in this area.
Furthermore, we have yet to master the core technology required for manufacturing 3D laser equipment, including the cutting head.
Only by reducing the cost of equipment and mastering its core technology can this valuable technology be widely utilized in fields such as automobile manufacturing, aerospace, and beyond.
3. Intellectualization
When it comes to three-dimensional laser cutting, we need to consider not only the position and orientation of the laser optical axis, defocusing amount, and other factors but also potential interference or collisions between the workpiece or fixture and the laser head.
Currently, there are software solutions available that can enable the machine tool to avoid such interference automatically, such as Tebis’ five-axis laser cutting module.
Teaching is a well-established method for inputting cutting trajectories, but it has some drawbacks, including being time-consuming, labor-intensive, and less accurate.
Before processing, 3D parts often have unique shapes and irregularities. In fact, due to the effects of gravity and other factors, their shapes may differ from the original design. Therefore, it may take some time to achieve direct CAD to CAM processing for 3D parts in laser cutting.
4. High integration
Due to the high cost of single laser equipment, the diversification of functions has always been the focus of laser equipment development. Currently, there are no fully matured laser processing methods for general three-dimensional laser equipment, such as integrated cutting, welding, surface treatment, etc.
While some equipment can cut, weld or punch holes, it tends to focus on one processing method and weaken other functions. This is because different processing methods have varying requirements for equipment, and the supporting facilities required are also different. As a result, factories tend to use dedicated machines for each processing method.
“High integration” is a relative concept, and it is not possible to integrate too many processing methods into a single equipment. Devices equipped with each processing method can interfere with each other when integrated. Additionally, these devices tend to be more expensive after integration due to their strong specificity.
5. Theoretical research
As of now, there is no relatively comprehensive three-dimensional cutting model available due to the complexity of laser cutting.
Establishing a database of laser cutting process parameters and an expert system is crucial for laser processing.
Conclusion
Currently, most three-dimensional laser cutting equipment in China is imported at a high cost, with a gap in theoretical research that mainly focuses on realizing the spatial trajectory and cutting process of three-dimensional parts.
There has been no in-depth study on the interaction between laser, material, and gas during the laser cutting process of three-dimensional parts, specifically the mechanism behind three-dimensional laser cutting.
There is a significant gap between domestic and foreign advanced technology in laser 3D cutting, particularly in equipment development and the lack of high-power lasers with high beam quality.
Therefore, there are still many areas where this technology requires further research and development to strengthen its capabilities.
