Comparison of ultrasonic welding and laser welding in solar panel production

1. Product aesthetics PK

Laser welding is to use high-energy laser to melt the welded metal to create a connection. In the solar heat absorption plate welding, a welding spot is welded with an interval of 3-5mm. Laser welding does not require pressure on the welded workpiece, the overall deformation is small, and the surface damage to the heat absorption layer is small, while ultrasonic metal welding will cause wave-shaped deformation on the surface of the sheet due to pressure, although it can be avoided by surface embossing Deformation, but it will still form a welding mark of about 3mm on the surface of the solar heat absorber. Therefore, the appearance of laser welding products will be better than ultrasonic metal welding. In this round of competition, laser welding is better than ultrasonic metal welding.

2. Persistence PK

The strength of laser welding solder joints is poor, and the solder joints are easy to break when the heat and cold alternate frequently or are subjected to external forces. Ultrasonic metal welding uses vertical pressure to make two objects to be welded overlap, and they are combined into a solid connection by ultrasonic vibration pressure. The bonding time is short and the bonding part does not produce cast structure defects. Therefore, the welding position is uniform and stable, and the ultrasonic metal The welding has passed the 90-degree vertical bending test and there is still no fracture. In this round of competition, ultrasonic metal welding is better than laser welding.

3. Thermal conductivity PK

The use of laser welding will change the physical structure of the welded object, thereby affecting its electrical or thermal conductivity, and laser welding will result in a small heat conduction area between the metal sheet of the solar collector and the copper tube, which affects the heat transfer efficiency. Ultrasonic metal welding does not have this problem. Ultrasonic welding can reduce the temperature effect of the material to a lower level, so as not to change the metal structure. Therefore, the electrical conductivity or thermal conductivity after welding is extremely good, and the resistivity is extremely low or nearly zero. Ultrasonic metal welding has become conductive and thermally conductive material welding. It is a better choice, this performance can obviously produce advantages that cannot be achieved by laser welding when applied to flat panel solar collectors. According to the test, the transmission efficiency of ultrasonic metal welding products is about 3% higher than that of 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 obviously better than laser welding.

4. Energy PK

As a representative product of low carbon, energy saving and environmental protection, solar water heaters are widely recognized by society and consumers. The energy consumption indicators in the production process have also attracted much attention. The welding of solar collectors is one of them. From the comparative analysis of welding principle, it can be known that ultrasonic metal welding can reduce the temperature effect of the material to a low level (the temperature of the welding zone does not exceed 50% of the melting temperature of the welded metal), so as not to change the metal structure, so it does not It will anneal the metal workpiece and does not require cooling water. In terms of energy consumption, ultrasonic welding can be carried out between the same type of metal and different types of metal, which consumes much less energy than laser welding. In this round of competition, ultrasonic metal welding is better than laser welding.

5. Cost PK

1. Equipment cost: Internationally, ultrasonic spot welding machine and laser welding machine are at the same price, but Minghe Ultrasonic Co., Ltd. has introduced the first fully automatic whole-plate ultrasonic metal welding in the solar thermal industry through the introduction of foreign technology and independent research and development. The machine has completely broken the situation that my country's high-precision ultrasonic welding equipment needs to rely on foreign imports, and has basically reduced the price of domestic ultrasonic welding machines by half. The purchase cost of a single device of ultrasonic metal welding machine is lower than that of laser welding machine, and the purchase ratio of the two is usually 300,000:1 million (the price of domestic laser welding machine is also falling rapidly, about 700,000). The laser welding machine generally has two laser welding heads, and the ultrasonic machine generally has one welding head. For the same capacity, compared with one laser welding machine, the ultrasonic is slightly better than the laser.

2. The cost of use: First, laser welding is suitable for thick materials, such as welding aluminum. The thickness of aluminum plate is generally selected as 0.4mm, while ultrasonic welding is suitable for thin products, such as aluminum plate. Generally, 0.2-0.3mm is enough. In terms of welding materials, ultrasonic is superior. The second is the cost of consumable parts. The consumable parts for laser welding are xenon lamps and filter elements, and the consumable parts for ultrasonic are welding heads. In general, laser welding consumables are cheaper than ultrasonic ones. Therefore, in this round of competition, ultrasonic metal welding is slightly better than laser welding.

6. Efficiency PK

The welding speed of 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. However, the currently selected process of ultrasonic welding is to roll grain and then weld, so a single machine Efficiency must be discounted. For the same production capacity, 2 ultrasonic welding machines are compared with 1 laser welding machine. In this comparison, ultrasonic is better than laser.