Laser welding machine is the professor used for laser material welding. According to its working mode, it can often be divided into laser mold welding machine (manual laser welding equipment), automatic laser welding machine, jewelry laser welding machine, laser spot welding machine, and optical fiber transmission laser Welding machines, galvanometer welding machines, handheld welding machines, etc. Special laser welding equipment includes sensor welding machines, silicon steel sheet laser welding equipment, and keyboard laser welding equipment. Weldable graphics are: point, straight line, circle, square or any plane graphics drawn by AUTOCAD software.

The laser welding machine is highly automated and the welding process is simple. The non-contact operation method can meet the requirements of cleanliness and environmental protection. Using laser welding machine to process the workpiece can improve work efficiency. The finished workpiece has a beautiful appearance, small weld seam, large welding depth and high welding quality. Laser welding machines are widely used in dental denture processing, keyboard welding, silicon steel sheet welding, sensor welding, battery sealing cover welding and so on. However, the cost of the laser welding machine is relatively high, and the accuracy requirements for the assembly of the workpiece are also relatively high, and there are still limitations in these aspects.

Laser welding uses high-energy laser pulses to locally heat the material in a small area. The energy of the laser radiation diffuses into the material through heat conduction, and the material is melted to form a specific molten pool. It is a new type of welding method, mainly for the welding of thin-walled materials and precision parts. It can realize spot welding, butt welding, stitch welding, sealing welding, etc., with high aspect ratio, small weld width, and small heat affected zone. Small deformation, fast welding speed, smooth and beautiful welding seam, no need to handle or simple processing after welding, high welding seam quality, no porosity, precise control, small focus spot, high positioning accuracy, easy to realize automation.

The working principle of laser welding machine: laser welding can be realized by continuous or pulsed laser beam. The principle of laser welding can be divided into heat conduction welding and laser deep penetration welding. The power density is less than 104~105 W/cm2 for heat conduction welding. At this time, the penetration depth is shallow and the welding speed is slow; when the power density is greater than 105~107 W/cm2, the metal surface is recessed into "holes" under the action of heat to form deep penetration welding. Features of fast welding speed and large aspect ratio.

The principle of thermal conduction laser welding is: laser radiation heats the surface to be processed, and the surface heat diffuses into the interior through thermal conduction. By controlling the laser pulse width, energy, peak power and repetition frequency and other laser parameters, the workpiece is melted to form a specific molten pool .

The laser welding machine used for gear welding and metallurgical sheet welding mainly involves laser deep penetration welding.

Laser deep penetration welding generally uses continuous laser beams to complete the connection of materials. The metallurgical physical process is very similar to electron beam welding, that is, the energy conversion mechanism is completed through the "key-hole" structure.

Under sufficiently high power density laser irradiation, the material will evaporate and form small holes. This steam-filled hole is like a black body, absorbing almost all of the incident beam energy. The equilibrium temperature in the cavity reaches about 2500 0C. The heat is transferred from the outer wall of the high-temperature cavity to melt the metal surrounding the cavity.

The small hole is filled with high-temperature steam generated by continuous evaporation of the wall material under the irradiation of the light beam. The four walls of the small hole are surrounded by molten metal, and the liquid metal is surrounded by solid materials (and in most conventional welding processes and laser conduction welding, the energy first Deposited on the surface of the workpiece, and then transported to the inside by transfer).

The flow of liquid outside the wall of the hole and the surface tension of the wall layer are maintained in a dynamic balance with the continuously generated steam pressure in the cavity. The light beam continuously enters the small hole, and the material outside the small hole is continuously flowing. As the beam moves, the small hole is always in a stable state of flow.

That is to say, the small hole and the molten metal surrounding the hole wall move forward with the forward speed of the leading light beam. The molten metal fills the gap left by the small hole and condenses, and the weld is formed.

And the above process happens very quickly, so the welding speed can easily reach several meters per minute.

Hand-held laser welding machine, using infrared precise positioning, flexible and convenient, firm welding, no consumables, smooth and fine welding seam and not easy to deform, mainly for laser welding of long-distance and large workpieces, widely used in large and medium-sized sheet metal, cabinets, and chassis , Long-distance spot welding, full welding, continuous welding, sealing welding of inner corners, outer corners, and seams of large workpieces such as aluminum alloy door and window frames, stairs, elevators, and stainless steel furniture.

Laser welding can be applied to the welding of titanium, nickel, tin, zinc, copper, aluminum, chromium, niobium, gold, silver and other metals and their alloys, as well as steel, Kovar and other alloys of the same material. It can be applied to the welding of various dissimilar metals such as copper-nickel, nickel-titanium, copper-titanium, titanium-molybdenum, brass-copper, and low carbon steel-copper. At the same time, it is also widely used in industries such as mobile phone communications, electronic components, glasses and watches, jewelry, hardware products, precision equipment, medical equipment, auto parts, and craft gifts.

The following key elements need to be considered:

1. Optical characteristics: spot size (laser rod diameter, fiber diameter and type, output head parameters), focal plane height, depth of field, spot position, spot angle of incidence;

2. Control characteristics: feedback control mode, choice of power waveform. The optical characteristics of the laser welding machine can be determined at the time of proofing, and the user can intuitively determine the welding effect when the product is first trial-produced, so I will not repeat it here, but focus on the laser control characteristics that affect the consistency of laser welding.

The laser welding machines currently sold in the market are mainly divided into two categories in terms of control characteristics: current negative feedback and laser power negative feedback.

Current negative feedback is a control method to control the current of the laser pumped xenon lamp to keep the xenon lamp current constant every time. However, the laser output power is not linearly proportional to the current of the pumped xenon lamp, and as the pumped xenon lamp is used for longer, the electro-optical conversion efficiency is significantly reduced, which will reduce the output laser energy, thereby affecting the consistency of the welding effect. Sex.

Laser power negative feedback is a control method in which a photodetector is added to the output end of the laser cavity, and the detected laser power is compared with the required laser power to control the pump current of the xenon lamp.

Laser power negative feedback is divided into real-time negative feedback and non-real-time negative feedback. Real-time negative feedback is a control method that compares the detected laser power with the required laser power within a laser power pulse, and then controls the pump current of the xenon lamp. Non-real-time negative feedback is a control method that compares the laser power waveform detected by the previous pulse with the set waveform, and then determines the current size of the next pulse laser pumped xenon lamp.

In addition, the laser welding machine using negative feedback control of laser power can easily control the waveform of laser power. In fact, for different materials, using different laser power waveforms can make the welding effect more exquisite, and sometimes even the traditional way cannot be welded. The material can also get better welding effect by changing the laser power waveform.

When selecting the laser power waveform, generally speaking, under the premise of outputting the same laser energy, the wider the pulse width, the larger the welding spot; the higher the peak power of the laser power waveform, the deeper the welding spot. At present, there is no complete set of laser power waveform setting methods. Users can explore the laser power waveform suitable for their products step by step during use.

The choice of laser welding machine is very important to the yield of batch processing; therefore, users can try to use the laser power real-time negative feedback welding machine to improve the product quality rate if conditions permit.

1. Simple operation: The handheld laser welding machine is easy to learn and use, and the operator can easily achieve high-quality welding results. Convenient and quick operating experience, to help companies solve the problem of welder recruitment.

2. High welding efficiency: The hand-held laser welding speed is fast, which is more than twice that of argon arc welding. It can easily double the production efficiency on the basis of saving 2 welding workers.

3. Welding without consumables: the welding operation in most people's impression is "left hand goggles, right hand clamp welding wire". However, with the handheld laser welding machine, welding can be easily completed without wire filling during the operation, and the material cost in production and processing is reduced.

4. Good welding effect: Hand-held laser welding is hot-melt welding. Compared with traditional welding, laser welding has a higher energy density and can achieve better welding results.

5. High energy efficiency conversion: People who don't understand, after knowing the effect of laser application, will naturally wonder whether the energy consumption of laser equipment is very high. The fact is just the opposite. The photoelectric conversion efficiency of the laser is as high as 30%, and the energy consumption is lower.

6. Convenient and flexible to use: Hand-held laser welding, no fixed-point workstation, free and flexible, and a wide range of reach.

7. The welding seam does not need to be polished: after traditional welding, the welding point needs to be polished to ensure smoothness and no roughness. The hand-held laser welding precisely reflects more advantages in the processing effect: continuous welding, smooth and no fish scales, beautiful and no scars, and fewer follow-up polishing procedures.

8. Dedicated swing welding head: large light spot, wide range of use, can be adapted to the welding of a variety of products.

The following key elements need to be considered:

1. Optical characteristics: spot size (laser rod diameter, fiber diameter and type, output head parameters), focal plane height, depth of field, spot position, spot angle of incidence;

2. Control characteristics: feedback control mode, choice of power waveform. The optical characteristics of the laser welding machine can be determined at the time of proofing, and the user can intuitively determine the welding effect when the product is first trial-produced, so I will not repeat it here, but focus on the laser control characteristics that affect the consistency of laser welding.

The laser welding machines currently sold in the market are mainly divided into two categories in terms of control characteristics: current negative feedback and laser power negative feedback.

Current negative feedback is a control method to control the current of the laser pumped xenon lamp to keep the xenon lamp current constant every time. However, the laser output power is not linearly proportional to the current of the pumped xenon lamp, and as the pumped xenon lamp is used for longer, the electro-optical conversion efficiency is significantly reduced, which will reduce the output laser energy, thereby affecting the consistency of the welding effect. Sex.

Laser power negative feedback is a control method in which a photodetector is added to the output end of the laser cavity, and the detected laser power is compared with the required laser power to control the pump current of the xenon lamp.

Laser power negative feedback is divided into real-time negative feedback and non-real-time negative feedback. Real-time negative feedback is a control method that compares the detected laser power with the required laser power within a laser power pulse, and then controls the pump current of the xenon lamp. Non-real-time negative feedback is a control method that compares the laser power waveform detected by the previous pulse with the set waveform, and then determines the current size of the next pulse laser pumped xenon lamp.

In addition, the laser welding machine using negative feedback control of laser power can easily control the waveform of laser power. In fact, for different materials, using different laser power waveforms can make the welding effect more exquisite, and sometimes even the traditional way cannot be welded. The material can also get better welding effect by changing the laser power waveform.

When selecting the laser power waveform, generally speaking, under the premise of outputting the same laser energy, the wider the pulse width, the larger the welding spot; the higher the peak power of the laser power waveform, the deeper the welding spot. At present, there is no complete set of laser power waveform setting methods. Users can explore the laser power waveform suitable for their products step by step during use.

The choice of laser welding machine is very important to the yield of batch processing; therefore, users can try to use the laser power real-time negative feedback welding machine to improve the product quality rate if conditions permit.

1. There should be no fire or unknown liquid around the installation site

Compared with common types of welding machines, hand-held laser welding machines belong to the category of high-precision devices. Once an unknown liquid penetrates or is disturbed by an open flame, the parts in key positions will be damaged to varying degrees. In order to prevent the occurrence of this phenomenon from the root cause, it is necessary to implement a full range of investigation work on the installation site to eliminate unknown liquids and potential fire sources.

2. If abnormal conditions are found, the maintenance should be stopped immediately

The quality of the reputable hand-held laser welding machine of the manufacturer can withstand the test, but if the operation method is improper, the minor problem is not found in time, and it is rapidly developing in the direction of expansion. The recommended method is to know whether the operating status of the handheld laser welding machine is normal, and if an abnormality is caught, it must be repaired immediately.

3. Regular maintenance of important parts

Similar to high-precision devices such as hand-held laser welding machines, important components will greatly interfere with the service life of the device. The inspiration is that these parts need to be maintained regularly. Specific maintenance work is not limited to replenishing lubricating oil, checking the running-in between parts, etc. As for the corresponding implementation steps, you need to ask professionals.

The laser welding machine is mainly composed of electronic components, precision instruments and optical components, and has high requirements for the use environment and daily maintenance.

(1) When the equipment is not working, cut off the power supply of the welding machine and the computer.

(2) When the equipment is not working, cover the site lens to prevent dust from polluting the optical lens.

(3) When the equipment is working, the circuit is in a high voltage state. Non-professionals should not perform maintenance during startup to avoid electric shock accidents.

(4) When the equipment fails, the power supply should be cut off immediately.

(5) When the equipment is used for a long time, the dust in the air will be adsorbed on the lower end of the focusing lens, and the light will reduce the power of the laser and affect the welding effect; heavy will cause the optical lens to absorb heat, overheat and burst. When the welding effect is not good, carefully check whether the focusing mirror is contaminated.

If the surface of the focusing lens is contaminated, remove the focusing lens and clean its lower end surface.

When disassembling the focusing lens, be careful not to damage or fall; at the same time, do not touch the surface of the focusing lens with your hands or other objects.

The cleaning method is to mix absolute ethanol (analytical grade) and ether (analytical grade) in a ratio of 3: 1, use a long-fiber cotton swab or lens paper to penetrate the mixed solution, and gently scrub the lower end of the focusing lens. Every time you wipe one side, you must replace the cotton swab or lens paper.

(6) During the working process of the electric welding machine, do not move the electric welding machine to avoid damage to the machine.

(7) Do not put piles or other objects on the welding machine, so as not to affect the heat dissipation effect of the machine.

Simple troubleshooting:

(1) Close the cabinet and open it, but there is no response when the key switch is turned on;

A: Measure whether the main power cord has voltage input;

B: Check whether the emergency stop switch is pressed (just turn it to the right and pop out).

When it is turned on normally, undervoltage is displayed on the right side of the screen

A: Check whether the waterway is normal (whether the water tank has an alarm or whether there is tap water);

B: Turn off the power and check whether the electrode clamps at both ends of the xenon lamp are loose;

(3) When the machine is working, the laser energy suddenly weakens

A: Check whether the protective lens under the laser focusing lens is damaged;

B: Check whether the water temperature of the water tank is high;

C: Open the dust cover of the light path, check whether there is condensation in the laser cavity (wipe the water droplets with a paper towel), and check whether there are water droplets at both ends of the laser rod (wipe gently with a clean cotton swab);

D: When the water tank is working, observe whether there is water seeping from both ends of the laser rod (if there is, please stop), the sealing ring may be damaged.

1. Educate and train the staff operating the hand-held fiber laser welding machine so that they (she) understand the potential risks that may arise when operating this level of laser, and stop appropriate laser safety exercises for them (her), and Emergency measures when risks are present. Since laser damage to eyes is irreversible, training and education to understand and control the safe use of lasers is necessary.

2. The management and use of lasers must be stopped by professional (professional) personnel, and those who have not been trained and educated are not allowed to open and use laser machines. For example, an interlock key switch is installed on the trigger system of the laser to ensure that only the key is used to turn on the interlock switch to trigger the start, and the key can not be pulled out. Regarding the room where the laser is installed, there must be bright light. In a bright light environment, the pupils of the eyes are reduced to prevent the laser beam from entering the eyes to reduce the amount of light transmitted to the retina. Regarding the height of the laser, the path of the laser beam should avoid the horizontal position of the eyes of a normal person when standing or sitting, and the visual axis cannot be parallel to the light outlet.

3. Do not aim the laser beam at the human body, especially the eyes, without any reason for the laser welding head of the laser. Because it is extremely difficult to recover from laser damage to eyes, they are all permanent damages, and each person only needs one pair of eyes in his life. You must always keep in mind that before turning on the laser, you must advise the personnel on the scene of possible hazards, and Wear safety glasses. Post risk signs at obvious locations outside and outside the work area with strong lasers, and on the doors of laser operating rooms and laboratories.

4. Strict protective measures shall be taken when debugging the optical system of the laser to ensure that human eyes are not reflected by the original laser beam and the mirror reflection beam. That is, the visual axis is not coaxial with the original beam and the mirror reflected beam.

5. Use optical instruments to observe the laser beam, such as binoculars, microscopes, telescopes, etc., to observe the laser beam, the possibility of laser damage to the eyes is increased. When using such optical instruments, strict safety calculations must be carried out, and optical filters and appropriate interlocking protective equipment must be added to ensure that the amount of reflection on the human eye is lower than the safety standard value of the laser.

6. Choose maintenance glasses with suitable optical density to enhance eye protection.

7. Post warning signs on the conspicuous positions of the laser equipment, laser housing and operation panel, and adopt the signs of "risk" or "pay attention" according to the degree of detailed damage of the laser, and it is better to be eye-catching.

The hand-held fiber laser welding machine is the product of the development of science and technology, which accommodates the wisdom of scientists. We only pay attention to the safety management measures of the laser, so that it can better serve people and produce more and better products in business.

1. Preparation before starting

1. Check the power supply of the laser welding machine and whether the water circulation is normal;

2. Check whether the equipment gas in the machine is normal;

3. Check that the surface of the machine is free of dust, spots, oil, etc.

2. Boot

1. Turn on the power and turn on the main power switch;

2. Turn on the water cooler, laser generator, etc. in order;

3. Open the argon valve and adjust the gas flow;

4. Enter the current working parameters to be executed

5. Perform welding operations;

Three, shutdown

1. Exit the program and turn off the laser generator;

2. Turn off the dust collector, water cooler and other equipment in order;

3. Close the argon cylinder valve;

4. Turn off the main power switch