Solar welding equipment process: laser PK ultrasonic
Release time: 2015-08-09 17:23:36 Views: 1546
In the production of flat-plate solar collectors in the solar thermal utilization industry, whether laser welding technology is stable or ultrasonic metal welding technology has more advantages has been a hotly debated topic in the industry. The battle between solar water heaters and flat solar water heaters. In the process of long-term process technology comparison and actual product comparison, two major technical camps of laser welding and ultrasonic metal welding have also formed, and the "battery battle" between the two.
This article attempts to make a comprehensive comparison between laser welding and ultrasonic metal welding, and analyzes the differences and their advantages and disadvantages. First of all, we distinguish between the two welding methods from the working principles of laser welding and ultrasonic metal welding.
Laser welding is the use of thermal energy generated by high-energy laser pulses to melt metal materials to produce connections. It is essentially the same as arc welding, except that arc welding is used to generate thermal energy instead of laser. Representing manufacturers such as Shenzhen Lianying Laser.
Ultrasonic metal welding is the use of high-density energy generated by high-frequency mechanical vibration of the ultrasonic to plastically deform the workpiece surface and destroy the surface layer under pressure, so that the welded metal is physically connected at normal temperature. Ultrasonic metal welding neither transfers current to the workpiece nor introduces high-temperature heat sources to the workpiece. It only converts mechanical kinetic energy into frictional work deformation energy and the resulting temperature rise under the combined action of static pressure and elastic vibration energy. So that the workpiece is connected in a solid state. Representing manufacturers such as Foshan Chuxin Electromechanical.
According to the comparison of welding principles, laser welding realizes the connection of objects by changing the physical structure of the object at high temperature, while ultrasonic metal welding can directly connect in a solid state without changing the physical structure of the object.
So, which of these two welding technologies has more advantages and is more suitable for application in the field of flat panel solar energy?
Round 1: Product aesthetics PK
Laser welding is the use of high-energy lasers to melt the welded metal to create a connection. In the solar heat absorption plate welding, welding is performed in the form of a welding point with an interval of 3-5mm. Laser welding does not require pressure on the workpiece to be welded, the overall deformation is small, and the surface of the heat absorbing layer is small. Ultrasonic metal welding will cause wavy deformation of the sheet surface due to pressure, although it can be avoided by surface embossing. Deformation, but will still form about 3mm welding marks on the surface of solar heat absorption. Therefore, the appearance of laser welding products is better than ultrasonic metal welding. In this round, laser welding is better than ultrasonic metal welding.
Round 2: Effect Persistence PK
The strength of laser welding joints is poor, and the welding joints are easy to break when cold and heat are alternated frequently or under external force. In ultrasonic metal welding, two objects to be welded are overlapped by vertical pressure, and the solid state connection is formed by ultrasonic vibration and pressure. The bonding time is short and the bonding part does not cause casting structure defects. Therefore, the welding position is uniform and strong. After welding, there was no fracture after 90-degree vertical bending test. In this round of competition, ultrasonic metal welding is better than laser welding.
Third round: Thermal conductivity PK
The laser welding will change the physical structure of the object being welded, which will affect its conductivity or thermal conductivity. Laser welding will result in a small absolute heat transfer area between the solar collector metal sheet and the copper tube, which will affect the heat transfer efficiency. This problem does not exist with ultrasonic metal welding. Ultrasonic welding can minimize the temperature effect of the material, so that the metal structure does not change. Therefore, the electrical conductivity or thermal conductivity is very good after welding, and the resistivity is very low or almost zero. Ultrasonic metal welding has become a conductive, thermally conductive material. The best choice, this performance in the application of flat solar collectors can obviously produce advantages that cannot be achieved by laser welding. According to tests, the ultrasonic metal welding products have a conduction efficiency about 3% higher than laser welding (that is, the water temperature is about 3% higher under the same working conditions). In this round of competition, ultrasonic metal welding is significantly better than laser welding.
Round four: energy consumption PK
Solar water heaters are widely recognized by society and consumers as a representative product of low-carbon energy conservation and environmental protection. The energy consumption indicators in the production process have also attracted much attention. The welding of solar collectors is one of them. From the comparison and analysis of welding principles, it can be known that ultrasonic metal welding can minimize the temperature effect of the material (the temperature of the welding zone does not exceed 50% of the absolute melting temperature of the welded metal), so that the metal structure does not change, so it does not change It can anneal metal workpieces and does not require cooling water. In terms of energy consumption, ultrasonic welding can be performed between the same metal and different metals, which consumes much less energy than laser welding. In this round of competition, ultrasonic metal welding is better than laser welding.
Round 5: Cost PK
First, the cost of equipment: Internationally, the price of ultrasonic welding machine and laser welding machine is equivalent, but Chuxin Mechanical and Electrical Company introduced the first fully automatic ultrasonic metal welding machine for the entire solar panel industry through the introduction of foreign technology and independent research and development. The situation that China's ultrasonic welding equipment needs to rely on foreign imports has been completely broken, and the price of domestic ultrasonic welding machines has been basically reduced by half. The purchase cost of a single piece of equipment for an ultrasonic metal welding machine is lower than that of a laser welding machine, and the procurement ratio of the two is usually 300,000: 1 million (now the price of domestic laser welding machines is also falling rapidly, to about 700,000). Laser welding machines generally have two laser welding heads, and ultrasonic machines generally have one welding head. For the same production capacity, two ultrasonic welding machines compare with one laser welding machine, and the ultrasonic wave is slightly better than the laser.
The second is the cost of use: First, laser welding is suitable for thick materials, such as welding aluminum. The thickness of aluminum plates is generally 0.4mm, while ultrasonic welding is suitable for thin products, such as aluminum plates, generally 0.2-0.3mm. In terms of welding materials, ultrasound is superior. The second is the cost of consumables. The consumables for laser welding are xenon lamps and filter elements. The consumables for ultrasound are welding heads. In general, laser welding consumables are cheaper than ultrasound. Therefore, in this round of competition, ultrasonic metal welding is slightly better than laser welding.
Round 6: Efficiency PK
Ultrasonic metal welding is faster than laser welding: the typical ultrasonic metal welding speed is 8 m / min for copper welding and 12 m / min for aluminum welding, but the currently selected process for ultrasonic welding is rolling and welding, so a single machine Efficiency has to be doubled. For the same production capacity, two ultrasonic welding machines are compared with one laser welding machine. In this comparison, ultrasonic waves are superior to lasers.
After comparing these opposites, we find that ultrasonic metal welding is superior to laser welding in welding process and comprehensive performance in the solar industry. Moreover, from the experience of use, ultrasonic metal welding, as the main welding technology in the solar energy field in China, has rich application experience. This is why many solar companies that have launched flat panel projects in the past two years have also selected ultrasonic metal welding.
As for the problem of the high cost of welding equipment that many solar companies have worried about before, it has been greatly alleviated with the launch of the fully automatic full-board ultrasonic metal welding machine independently developed by Chuxin Mechanical and Electrical Company. Which welding technology has more advantages, the market choice will become the most effective way to verify. The author, like the majority of readers, looks forward to the further leap in China's metal welding technology, enabling many production enterprises and consumers to experience and enjoy technology. Fruitful results from progress.