Laser Plastic Welding Technology Elevates Manufacturing Quality of Plastic Products

Laser Plastic Welding Technology Elevates Manufacturing Quality of Plastic Products

Laser welding, as a technology for fusing plastic products, is primarily used to join sensitive plastic components such as automotive plastic parts, plastic electronic sensor components on circuit boards, complex-shaped plastic products, and medical plastic devices that demand stringent sealing and cleanliness requirements.

Below, the Songsheng Optoelectronics team will briefly explain how plastic laser welding technology effectively enhances the high-quality welding performance of plastic products.

Schematic Diagram of Laser Plastic Welding Fundamentals

Plastic welding is a process that involves heating the plastic interface to soften or melt it. Under applied pressure and over time, polymer chains diffuse across the interface, forming entanglements that result in a strong weld.

Currently, traditional welding technologies in China include friction welding, ultrasonic welding, and hot gas welding. Compared to these conventional plastic welding methods, laser plastic welding offers the following advantages for plastic products:

1. Superior weld quality – Laser welding produces strong, precise, and stable seams without generating pollution, making it an environmentally friendly welding technology.

2. Lower cost and higher performance – With continuous advancements in laser welding equipment, costs have decreased while performance has improved. Compared to other welding systems, laser welding offers easier maintenance, user-friendly operation, and long-term durability.

3. Precise control of the heat-affected zone in plastic laser welding makes it      particularly suitable for miniaturized electronic and electrical products.

4. Extremely fast heating and cooling rates significantly reduce thermal stress and      vibration stress in plastic products.

5. Plastic laser welding produces clean, aesthetically pleasing seams without      vibration, ensuring no damage to internal electronic components.

6. Laser welding is easy to control, involves non-contact processing, and offers strong adaptability, making it highly operable for complex structures or extremely small weldments.

Integrated Galvanometer Coaxial Vision Scanning System Diagram

Songsheng Optoelectronics has independently developed an integrated constant-temperature galvanometer coaxial vision scanning welding system in response to market demands. This system is not only suitable for precision soldering but can also be used for high-precision welding of plastic products.

The galvanometer-based constant-temperature coaxial vision processing system is specifically designed for high-precision positioning in galvanometer scanning applications. The CCD observation image is fully coaxial with the laser beam focus, and when paired with an F-θ lens and dark-field illumination, it achieves "what you see is what you get" (WYSIWYG) laser processing.

After calibration, the absolute positioning accuracy of laser processing can reach below 0.02 mm, and when combined with software compensation, it can nearly eliminate processing errors caused by galvanometer thermal drift.

The scanning objective lens adopts a telecentric design, eliminating common issues associated with conventional scanning lenses and ensuring uniform marking quality across the entire working range. The integrated system architecture enhances stability and reliability, while the internal coaxial CCD optical system delivers superior imaging quality, making it easier for software recognition compared to traditional setups.

Specifically designed for precision welding, the system can control the cross-stage movement to designated positions based on fiducial markers on the workpiece, effectively avoiding welding inaccuracies caused by part misalignment. Additionally, the vision positioning system doubles as a real-time monitoring device, with CCD imaging providing live observation of the welding process.

Galvanometer Scanning Welding Process Diagram for PP Plastic Case

Direct Diode Laser Welding System with Temperature Feedback: The temperature feedback function enables precise temperature control during welding, allowing thermal regulation in micro-areas as small as 1mm diameter with ±2℃ accuracy. This precise temperature control ensures optimal welding results while preventing workpiece damage.

The integrated design ensures system stability and reliability, incorporating galvanometer scanners, coaxial infrared temperature measurement, coaxial CCD imaging system, coaxial laser transmission system, and scanning objective lens assembly.

Songsheng's proprietary technology (China-exclusive): Multi-point coaxial optical path system. Featuring specially-designed infrared lenses, this system ensures perfect alignment of laser, imaging, and infrared temperature measurement points at any working position - even when deviating from lens center. A truly integrated temperature-monitoring processing system.