1. Shielding gas blowing method There are currently two main ways to blow shielding gas: One is side-blowing shielding gas, and the other is coaxial shielding gas. The specific choice of the two blowing methods is a comprehensive consideration of many aspects. In general, it is recommended to use the side-blowing shielding gas method. 2.Principles for selecting shielding gas blowing methods It is better to use the lateral axis for straight line welds and the coaxial axis for plane closed figures. First of all, it should be made clear that the so-called "oxidation" of the weld is only a common name. In theory, it means that the weld reacts chemically with harmful components in the air, resulting in poor weld quality. It is common that the weld metal reacts chemically with oxygen, nitrogen, hydrogen, etc. in the air at a certain temperature. Preventing the weld from being "oxidized" is to reduce or avoid contact between such harmful components and the weld metal in a high-temperature state. This high-temperature state is not just the molten molten metal, but the entire time period from when the weld metal is melted to when the molten metal solidifies and its temperature drops below a certain temperature. For example, titanium alloy welding can quickly absorb hydrogen when the temperature is above 300℃, oxygen when it is above 450℃, and nitrogen when it is above 600℃. Therefore, the titanium alloy weld needs to be effectively protected after solidification and the temperature drops below 300℃, otherwise it will be "oxidized". From the above description, it is not difficult to understand that the blown protective gas not only needs to protect the weld molten pool in time, but also needs to protect the welded and just solidified area. Therefore, side-blowing protective gas is generally used, because this protection method has a wider protection range than the coaxial protection method, especially for the area where the weld has just solidified. For engineering applications, not all products can use side-blowing protective gas. For some specific products, only coaxial protective gas can be used. Targeted selection is required based on product structure and joint form. 3. Selection of specific shielding gas blowing methods (1) Straight welds The weld shape of the product is a straight line, and the joint form can be a butt joint, lap joint, internal angle joint or lap weld joint. For this type of product, it is best to use the side-blow shielding gas method. (2) Plane closed figure welds The weld shape of the product is a closed figure such as a plane circle, a plane polygon, or a plane multi-segment line. The joint form can be a butt joint, lap joint, lap weld joint, etc. For this type of product, it is best to use the coaxial shielding gas method. The selection of shielding gas directly affects the quality, efficiency and cost of welding production. However, due to the diversity of welding materials, the selection of welding gas is also relatively com...

First, the definition of shielding gas: Why is shielding gas needed? Because during laser welding, the high-energy heat source of the laser will quickly melt the material and form a keyhole in the molten pool. The metal in the molten state is very active and easily undergoes oxidation reaction with oxygen in the atmosphere. It is very violent. Intuitively, there are a lot of spatters, pores, and welding slag everywhere, just like fireworks. Therefore, the role of shielding gas is to isolate the molten pool from oxygen. The shielding gas gushes around the molten pool to form a flowing inert gas environment, and the molten metal and oxygen are in direct contact. Another function of laser welding shielding gas is to blow away the plasma (the high-energy laser makes the metal ionize and produce a cloud of mist above the molten pool, which will shield the laser energy from reaching the molten pool directly, and the laser will have a certain loss when passing through the plasma). There are three main types of shielding gas: N2, Ar, and He. Their physical and chemical properties are different, and therefore the effects on the weld are also different. Nitrogen N2: The ionization energy of N2 is moderate, higher than that of Ar and lower than that of He. The degree of ionization under the action of laser is general, which can effectively reduce the formation of plasma cloud, thereby increasing the effective utilization rate of laser. Nitrogen can react chemically with aluminum alloy and carbon steel at a certain temperature to produce nitrides, which will increase the brittleness of the weld and reduce the toughness, and have a greater adverse effect on the mechanical properties of the weld joint. Therefore, it is not recommended to use nitrogen to protect aluminum alloy and carbon steel welds. The nitride produced by the chemical reaction of nitrogen with stainless steel can increase the strength of the weld joint, which is beneficial to the improvement of the mechanical properties of the weld, so nitrogen can be used as a shielding gas when welding stainless steel. Argon gas Ar: Ar has the lowest ionization energy, and the ionization degree is high under the action of laser, which is not conducive to controlling the formation of plasma cloud and will have a certain impact on the effective utilization rate of laser. However, Ar has very low activity and is difficult to react chemically with common metals. Moreover, Ar is not expensive. In addition, Ar has a large density, which is conducive to sinking above the weld pool and can better protect the weld pool. Therefore, it can be used as a conventional shielding gas. Helium gas He: He has the highest ionization energy, and the ionization degree is very low under the action of laser. It can well control the formation of plasma cloud. Laser can act well on metal, and He has very low activity and basically does not react chemically with metal. It is a good weld shielding gas, but the cost of He is too high. ...

The cooling system is one of the important components of the laser welding machine. If the cooling system fails, the equipment will stop working at a small level, and even the crystal rod may explode in severe cases. From this, we can see the importance of the cooling system of the laser welding machine. At present, the cooling systems of laser welding machines mainly include water cooling and air cooling systems. Among them, water cooling is the most widely used. The laser chiller is an individualized application of industrial refrigeration machines to the laser industry. It is a cooling water device that can provide constant temperature, constant flow and constant pressure. The working principle of water cooling of the laser chiller is to first inject a certain amount of water into the water tank in the machine, cool the water through the chiller cooling system, and then use the water pump to send the low-temperature cooling water to the equipment to be cooled. The cooling water in the chiller takes away the heat and then the temperature rises and flows back to the water tank to achieve the cooling effect. Its working principle is: 1. The laser welding machine chiller generally has a filter, which can effectively filter out obvious particulate impurities in the water, keep the laser pump cavity clean and prevent the possibility of water blockage. 2. The chiller uses pure water or deionized water, which is more conducive to the pump light source directly entering the laser material and can produce a better laser mode. 3. The chiller of the laser welding machine is generally equipped with a water pressure gauge, which can clearly know the water pressure in the laser waterway. 4. The chiller uses an imported compressor, the water tank and water pump are made of stainless steel, and the heat transfer coil is also made of stainless steel. This can fully ensure the stability of the chiller and the refrigeration effect. The temperature difference can be within 1°C. The lower the controlled temperature difference, the less the laser is affected by temperature. However, we recommend that the temperature difference be adjusted to about 1°C. 5. The chiller has flow protection. When the water flow is less than the set amount, there is a signal alarm, which can be used to protect the laser and related devices to be cooled. 6. The chiller of the laser welding machine has temperature protection. If the temperature is not suitable, a signal alarm will also appear. 7. The chiller has a series of adjustment functions, such as temperature adjustment and temperature difference adjustment.

The common auto parts marking methods on the market are: mold casting, electro-corrosion marking, stickers, screen printing, pneumatic marking and laser marking. Among them, although laser marking technology was born the latest, it has attracted widespread attention for its indelible marking since its birth. The main advantage of using laser for auto parts marking is that it is a fast, programmable, non-contact process with a long-lasting process that is usually not affected by the steps required in the production process or the harsh on-site environment it is subjected to. Of course, it also has disadvantages, such as the high initial cost of laser marking equipment and insufficient contrast of marking in some applications (such as marking plastic products). Laser, barcode and QR code are widely used in auto parts traceability. Barcode and QR code are popular technologies for product traceability in various forms today, and are fully applicable to all types of auto parts. Early auto parts marking mainly relied on marking serial numbers on products to meet traceability requirements. After the birth of barcodes, they were quickly applied to the identification of auto parts, but their small amount of information and poor fault tolerance prevented them from being fully popularized. This problem was not solved until the birth of QR code technology. A QR code is a 2D graphic similar to a chessboard that can hold a lot of information in a very small area. Since the 2D graphics of a QR code only require readout performance at a contrast ratio of 50% or even lower, the use of QR code graphics greatly increases the number of laser applications. The encoding of the QR code also has a built-in correction function, so the code can still be read even if part of the code is damaged for some reason. QR codes can also be decoded and encrypted in several different forms, and protection devices are placed in the data, making this type of marking more valuable for patented components. In addition to automatically generating barcodes, the marking software also supports QR code technologies such as DataMatrix, PDF417, QR Code, etc. Lasers can mark most materials used in automobiles with permanent, high-contrast marks. Laser marking machines can be used as stand-alone mass-production marking solutions for marking small workpieces, or they can be fully integrated into production lines. Flexible software control programs can customize any form of marking content. Lasers are becoming increasingly important in the automotive industry and are increasingly affecting our daily lives.

Laser marking machines use laser beams to mark permanent marks on the surfaces of various materials. The effect of marking is to expose the deep material through the evaporation of the surface material, thereby engraving exquisite patterns, trademarks and texts. In the Chinese laser industry, practitioners have made specific descriptions and classifications of it. After the enterprise customers state their requirements, they can recommend the selection of appropriate models according to the actual development situation. A. Classification of commonly used laser marking machines: 1. Fiber laser marking machine: The main technology is used to mark the required text, patterns, barcodes and other information graphics on plastic, electronic, metal, ceramic, tobacco and other material products. The fiber laser marking machine has the advantages of simple, fast and convenient operation, fast marking speed and clearness, which continuously optimizes the production management efficiency of enterprises. 2. UV laser marking machine: The industry used is the same as that of fiber laser marking machine, but the printed text, pattern, etc., when some fiber laser marking machines cannot engrave the required effect, the characteristics of UV laser marking machine are reflected, because UV laser marking machine belongs to the category of cold light, many products fiber laser marking machine cannot engrave satisfactory effect, UV laser marking machine can generally engrave. 3. Carbon dioxide laser marking machine: CO2 laser marking machine uses laser beam to mark the surface of various materials in various ways. Carve out patterns, trademarks, dates, LOGO or through text. At present, CO2 laser marking machine is mainly used in some Chinese wood, paper, etc. of enterprises. B. Advantages of laser marking machine: 1. Permanence: For example, the mark will not fade due to environmental factors (touch, acidic and reducing gases, high temperature, low temperature, etc.). 2. Anti-counterfeiting: The mark engraved by laser marking technology is not easy to copy and change, and has strong anti-counterfeiting to a certain extent. 3. Non-contact: Laser marking is processed by non-mechanical "light knife", which can print marks on any regular or irregular surface, and the workpiece will not generate internal stress after marking, ensuring the original precision of the workpiece. It does not corrode the working surface, there is no "tool" wear, no toxicity, and no pollution. 4. Wide applicability: Laser can be used as a processing method to process a variety of metals and non-metallic materials (aluminum, copper, iron, wood products, etc.). 5. High engraving accuracy: The laser marking machine engraves fine patterns on objects, with a minimum line width of 0.04mm. The marking is clear, durable and beautiful. Laser printing can meet the needs of printing a large amount of data on extremely small plastic parts. For example, it can print two-dimensional barcodes that require more...

Laser marking machine uses laser beam to permanently mark the surface of various materials. The effect of marking is to expose the deep material "engraving" traces through the evaporation of surface material or the chemical and physical changes of surface material caused by light energy, or to burn part of the material through light energy to show the pattern and text to be etched. There are two recognized working principles: 1. Hot processing: "Hot processing" has a laser beam with high energy density (it is a concentrated energy flow), which is irradiated on the surface of the processed material. The surface of the material absorbs the laser energy and produces a thermal excitation process in the irradiated area, so that the temperature of the surface (or coating) of the material rises, resulting in deformation, melting, ablation, evaporation and other phenomena. 2. Cold processing: "Cold processing" has (ultraviolet) photons with very high load energy, which can cut the chemical bonds in the raw materials (especially organic materials) or the surrounding medium, so that the raw materials are destroyed in a non-thermal process. This kind of cold processing has special significance in the laser marking process, because it is not thermal ablation, but cold peeling that cuts the chemical bonds without the side effect of "thermal damage", so it will not cause heating or thermal deformation to the inner layer and surrounding area of the processed surface. For example, in electronic manufacturing, excimer lasers are used to deposit chemical films on substrate materials and to create narrow grooves on semiconductor silicon wafers. Laser marking machine application industries: Widely used in integrated circuit chips, computer accessories, industrial bearings, watches, electronic and communication products, aerospace devices, various auto parts, home appliances, hardware tools, molds, wires and cables, food packaging, jewelry, tobacco, military affairs and many other fields for marking graphics and texts, as well as mass production line operations.

In order to meet the growing welding demand and the quality of welded joints, the welding industry urgently implements transformation and upgrading. Automatic welding robots have improved the level of automation and intelligence of welding. Enterprises use automatic welding robots to replace traditional welding. Before operating the welding robot, it is necessary to adjust the welding parameters according to the specifications of the weldment to help stabilize the welding quality. The welding parameters of the welding robot mainly include welding current, welding voltage, welding power source type, welding speed, etc. Setting the welding parameters properly can help the welding robot improve the welding efficiency while stabilizing the welding quality and clarify the production cycle of the product. When adjusting welding parameters, you need to pay attention to the following points: 1. Matching of welding current, voltage and welding wire. Welding current is an important welding parameter of the welding robot. The welding current is usually set together with the welding voltage. Before the welding robot enters mass production, debugging work needs to be carried out to set the welding current and voltage. In the case of short-circuit transition, the welding current increases, the welding voltage decreases, and the short-circuit current increases to a certain value, and thin welding wire can be used for welding; in the case of fine-grained transition, thick welding wire can be used for welding. When the welding current is low and the voltage is high, the six-axis welding robot is prone to welding spot spatter and workpiece deformation during the welding process. Only when the voltage is low, the welding process becomes relatively stable and can make the welds very good. Ground forming is conducive to companies using welding robots to weld thin plates. 2. Setting of welding speed. The welding speed of the welding robot needs to match the speed of the company's production line. During the welding process, if the speed is set too fast, welding defects will easily occur. If the speed is too slow, it will easily slow down the production cycle. Therefore, the welding speed needs to be set according to the production line. . 3. Welding direction. The automatic welding robot will weld according to the setting of the welding direction. There are two welding directions when setting up. One is the forward method, which means that the arc does not act directly on the workpiece, but pushes the molten pool away. The other is In the retreat method, the arc acts directly on the workpiece and avoids the molten pool. These two welding directions are set according to the actual situation. 4. Welding angle. The automatic welding robot will weld according to the setting of the welding direction. There are two welding directions when setting up. One is the forward method, which means that the arc does not act directly on the workpiece, but pushes the molten pool away. ...

A.Welding machine maintenance: 1.Clean the laser welding machine: The laser welding machine will produce dust, impurities, etc. during use, which will affect the stability of the machine output. Before cleaning, you need to cut off the power first and wait for the machine to cool down, then wipe the stained area and place it in a dry and clean environment after cleaning. 2.Check the cooling system: The cooling system is an important part of the laser welding machine. If the water is insufficient, it needs to be added to the appropriate water level. If the water quality becomes turbid, a clean water source must be replaced to keep the cooling system clear and at a suitable temperature. 3.Maintenance of parts: During long-term use of the laser welding machine, parts will be consumed and worn. If any problematic parts are found, they must be repaired or replaced in time to avoid affecting the welding quality. 4.Correctly operate the laser welding machine: The laser welding machine is a relatively advanced welding equipment with a complex structure. You need to pay attention to the sequence of starting up and shutting down, and check whether the indicator light lights up correctly. 5.Test the laser welding machine: Use some corner materials for test welding before welding, observe the operating status of the equipment and the welding quality, stop and investigate in time if there are any abnormalities, and contact the manufacturer to solve the problem. B.Welding gun maintenance: 1.Check the contact tip: The contact tip will be worn or stained with spatter during use, which will affect the formation of the weld. If it is damaged, replace it in time. 2.Pay attention to the temperature of the welding gun: The temperature of the welding gun increases after being used for a long time, especially in hot summer. It is best to place it in a ventilated place to carry out welding work. C.Chiller maintenance: 1.Place the chiller in a ventilated and cool place. It is recommended to use it below 40 degrees. When using a laser chiller, the machine room must be kept clean and well ventilated, and the condenser must be cleaned regularly to ensure that the unit can work normally. 2.The water should be changed regularly and the water tank should be cleaned regularly. The water should be changed regularly every 3 months. 3.The quality and temperature of the circulating water will affect the service life of the laser tube. It is recommended to use pure water and control the water temperature below 35 degrees Celsius. 4.When the unit fails and alarms to shut down, you should first press the alarm shutdown button and then check the cause of the fault. Remember not to force it to start operation before the fault is eliminated. 5.Regularly clean the condenser and dust filter of the chiller. 6.Unless there is an emergency during use, do not shut down the unit by cutting off the power supply; 7.In addition to daily maintenance, winter maintenance also needs to prevent freezin...