With the continuous development of heavy industry, laser cutting technology is developing from thin plate cutting to large-scale cutting of thick plate.
Laser cutting has gradually entered the era of high power.
In the new era, industrial manufacturing puts forward new requirements for metal plate cutting accuracy, speed and thickness. The power of laser cutting machine is becoming higher and higher.
From the perspective of industrial development, high-power laser cutting machine is not only the inevitable product of a certain stage, but also the general trend of industrial development.
In the field of sheet metal processing, the advantages of laser cutting machine are very prominent. Due to the advantages of high precision, high speed and good quality, it has gradually replaced the traditional processing technology and become the core equipment of sheet metal cutting.
From the rise of laser cutting machines, to the replacement of YAG, CO2 and other machines by fiber laser cutting machines, and then to the continuous introduction of high-power laser cutting machines, high-power equipment has become the general trend for cutting thick plates and cutting efficiency.
In recent years, high-power laser cutting machine has become a hot topic in the field of laser cutting. Many enterprises continue to launch optical fiber laser cutting equipment above 10000 watts.
For the sheet metal processing industry, the birth of high-power cutting equipment has greatly improved the thickness and efficiency of sheet metal cutting.
The emergence of this high-power cutting machine constantly breaks the limit of material cutting thickness.
The resulting reduction in the price of processing thick plates forms a good cycle and promotes the further expansion of the application field of laser cutting.
02 Brief introduction of high power laser cutting machine
(1) Introduction of high power cutting machine
Laser cutting machine can be divided into low power, medium power and high power according to power.
For stainless steel and carbon steel with general thickness, low-power laser cutting machine can cut well.
For cutting thick plates and cutting efficiency, high-power laser cutting machine can cut well.
Therefore, laser cutting machines with laser power above 10000 watts are collectively referred to as high-power laser cutting machines (see Figure 1).
Fig. 1 High power laser cutting machine
(2) Specifications of fiber laser power
According to the different thickness of laser cutting metal plate, the power specifications of the selected fiber laser on the high-power cutting machine are also different.
From the current development trend, in the metal processing market, large, medium and small enterprises are gradually upgraded to a variety of specifications, as shown in Table 1.
Table 1 Specifications of high power fiber laser
(3) Specification of gas used
When the high-power laser cutting machine works, in order to ensure the cutting accuracy, cutting speed, cutting section effect and many other advantages, the purity of oxygen used is required to be high, generally 99.99%.
03 Characteristics of high power laser cutting machine
3.1 Technological breakthrough
(1) High speed cutting machine with high dynamic performance
The machine tool equipped with 10000 watt fiber laser adopts a new triangular structure beam, which has the following characteristics:
① The weight is reduced by 30%, and the dynamic performance is significantly improved.
② The maximum moving speed can reach 200m / min and the acceleration is 4G.
③ The weight of the base is increased by about 20%, and the fixing mode of the machine tool is changed to eliminate the impact of high acceleration on the machine tool.
(2) New software system
Software and control system are like the brain and command center of machine tool.
In addition to the bonus brought by hardware upgrading, the difference in machine performance mainly comes from the difference of software and control system, and often varies greatly.
(3) It can realize stable cutting at a speed of 100M / min
① The response speed of the capacitive sensor is three times higher than that of the traditional cutting head.
② The z-axis speed is increased, the operation is non-stop and more smooth, the sheet cutting efficiency is increased by more than 30%, the efficiency of the leapfrog function is improved, and the acceleration adaptation function is improved.
③ Improve the functions of rapid perforation, precision perforation and remote diagnosis, and reserve an intelligent interface to realize the function of “industry 4.0”.
3.2 Characteristics of cutting head
The high-power cutting head is the core component to ensure cutting stability under the condition of high-power continuous operation, and has the following characteristics:
① The high-power cutting head has a better sealing and more sufficient cooling system, a wider range of focus and high-temperature resistant lenses.
② Under the influence of the high-power thermal lens effect, the beam will have focus drift when the cutting head works for a long time. In order to overcome the problem of focus drift, the high-power cutting head adopts a new gas path design structure and replaces the nozzle with a new structure, so as to improve the cutting speed and cutting stability.
3.3 High power laser cutting capability
(1) The thickness of cutting thick plates is increasing
At present, the thickness of aluminum alloy plate and stainless steel plate cut by high-power laser cutting machine can reach 40mm and 130mm respectively.
With the continuous upgrading of high-power laser cutting machine technology, the thickness of cutting materials will continue to increase, the price of processing thick plates will gradually decrease, and accelerate the application of high-power laser cutting machine in the field of thick plates.
Fig. 2 Workpiece for cutting thick plate
(2) Efficiency multiplication of thin plate in cutting
① When cutting stainless steel plate with thickness of 3 ~ 10mm, the cutting speed of 10000w laser cutting machine is more than twice that of 6000W.
② 10000w laser cutting machine can achieve fast bright surface cutting of 18 ~ 20mm / s in the cutting application of carbon steel, which is twice the ordinary standard cutting speed.
③ The carbon steel plate within 12mm can be cut with compressed air or nitrogen, and the cutting efficiency is 6 ~ 7 times that of oxygen.
3.4 Bed characteristics
(1) The equipment is equipped with super load-bearing mechanical structure
The high-power cutting machines are equipped with a cast iron bed, which is integrally cast with flake graphite cast iron with a minimum tensile strength of 200MPa, and the carbon content, compressive strength, vibration damping and wear resistance are greatly improved (see Fig. 3).
Fig. 3 Machine bed
(2) Characteristics of cast iron bed
① The bed has good lubrication performance, corrosion resistance and dimensional stability to reduce the machining error caused by bed vibration.
② Reduce the loss of the equipment in use, improve the stability coefficient by more than 30%, improve the quality accuracy by more than 30%, and improve the service life of the bed by more than 70 years.
3.5 Automatic nozzle replacement
(1) Manual nozzle change mode
During cutting, the nozzle shall be replaced according to the thickness and material of the cutting material
For many years, the nozzle has been replaced manually, which is not only inefficient and requires repeated work of technicians, but also difficult to ensure accuracy and stability after replacement.
How to efficiently and quickly replace the nozzle and ensure that each replacement is safe and accurate is a technical problem in the field of laser cutting.
(2) Automatic nozzle replacement technology
The high-power laser cutting machine applies the function of automatic nozzle replacement.
It can realize the functions of automatic replacement of nozzle, calibration of the laser head and automatic cleaning of the nozzle, and reduce the amount of manual repeated labor.
When the nozzle is automatically replaced, it can be realized by operating the corresponding command on the touch screen.
Automatic nozzle replacement technology has the following advantages:
1) Reduce the labor intensity and ensure the positioning accuracy and working stability when replacing the nozzle.
2) It is equipped with a perfect control system, which can automatically change the model and specification of the nozzle according to different materials and different plate thickness, reduce the time of manual replacement, and improve production efficiency.
3) Automatic nozzle replacement is a fully enclosed protective device, which provides a good guarantee for nozzle equipment and personal safety.
3.6 Lightning perforation and limit hole forming
(1) Lightning perforation
It has the advantages of short perforation time, small thermal focusing energy, stable starting point, and maintaining the stability of the servo system, which can ensure the best cutting effect.
The advantages of lightning perforation are shown in Table 2.
|Perforation time||Reduced by about 90%||Improve processing efficiency|
|Waste porosity rate||From about 10% to about 0.3%||Improve workpiece integrity|
|Save gas and electricity||The damage of laser and cutting head is reduced||Improve material utilization|
(2) Limit hole
The laser cutting industry has always believed that the thickness of the plate is the minimum diameter of the cutting hole
High power laser cutting machine can realize that the diameter of the smallest hole is 0.15 times of the plate thickness or even smaller, as shown in Figure 4.
Fig. 4 Minimum hole cutting sample
04 Advantages of high power laser cutting machine
(1) High speed
The laser cutting speed has exceeded 20m / min, the two-axis moving speed of the processing cutting machine can reach 250m / min, and the acceleration has reached about 10g during operation.
(2) High precision
Cutting in 1mm thick plate, about 500 pieces can be cut per minute for a small hole of about ϕ10mm. In the cutting process, the error between these holes is very small.
(3) Develop towards the thick plate
The power of high-power laser cutting machine is gradually increasing, and the size of the thick plate is also increasing.
(4) Developing towards large size
The processing size range of laser cutting technology is also increasing, and laser cutting technology has begun to develop towards large size.
(5) Automatic unmanned
It is necessary and urgent to develop automatic and unmanned laser cutting technology.
① The application of computer network technology makes laser cutting technology automatic and unmanned.
② The market demand for the application of this technology is also increasing, which urges the laser cutting technology to realize full-automatic unmanned.
Follow the pace of intelligent manufacturing according to the technical requirements of industry 4.0.
It adopts accurate graphic recognition technology, simple operation process and convenient human-computer intelligent interaction to realize the combination of laser and computer control, numerical control technology, optical system, high-precision and automatic positioning device, and integrates automatic discharge, cutting process database, remote fault diagnosis and remote control to meet the needs of mass and complex parts processing.
(1) Development of high power equipment
As a very ideal processing method in cutting processing, laser cutting represents the development direction of modern metal processing technology.
At present, high-power laser cutting machine is also carrying out key technology research and development in the fields of high speed, high precision, large format, three-dimensional cutting and special material cutting, so as to promote the technical development of high-power laser cutting to meet the growing market demand.
(2) High power equipment selection
When choosing high-power laser cutting equipment, some enterprises need to consider carefully: in addition to cutting speed and accuracy, we must check the stability and consistency of full-power continuous cutting, speed matching ability of machine tools, advanced quality of machine tools and precision life.
We can’t simply compare the price factors like buying low-power laser cutting equipment.
High power means high investment, and high investment implies high risk.
When entering this high return market, enterprises must recognize its risk.