The Innovative Application of Color Spectrum Laser Transmittance Meter in the Quality Evaluation of Plastic Welding

With the extensive application of plastic products in numerous fields such as automobiles, electronics, and medical care, plastic welding technology, as a key means for connecting plastic products, its welding quality directly affects product performance and service life. Traditional methods for evaluating plastic welding quality, such as visual inspection and destructive tests, have limitations including strong subjectivity, inability to comprehensively reflect internal quality, and potential damage to the products. The emergence of laser transmittance meters has provided a brand-new, efficient, and accurate solution for evaluating plastic welding quality.

I. Working Principle of Laser Transmittance Meter

The laser transmittance meter operates based on the principle of light transmission. When a laser beam of a specific wavelength is irradiated onto a plastic sample, some of the light is absorbed, some is scattered, and the remaining light passes through the plastic. The instrument precisely measures the incident light intensity and the transmitted light intensity through a high-precision light detector. For the assessment of plastic welding quality, the laser transmittance meter can sensitively detect the difference in transmittance between the welded and non-welded areas. Welding defects, such as bubbles, inclusions, and incomplete penetration, can alter the microstructure within the plastic and subsequently affect the laser transmittance. For instance, the presence of bubbles will increase light scattering, resulting in a decrease in transmittance; inclusions and foreign substances will change the light propagation path, leading to abnormal transmittance. By analyzing the changes in transmittance, the welding quality can be accurately evaluated.

II. Characteristics and Advantages of the Color Spectrum Laser Transmittance Meter TH-20

The Color Spectrum Laser Transmittance Meter TH - 200 demonstrates outstanding performance in the assessment of plastic welding quality. It features a high-precision optical detection system that enables precise measurement of laser transmittance, with a measurement accuracy of ±0.1%. This high-precision characteristic enables it to sensitively capture minute changes during plastic welding, providing a solid foundation for accurate assessment of welding quality.

TH - 200 has a wide spectral measurement range, covering various commonly used laser wavelengths, and is adaptable to the needs of different plastic materials and welding processes. Whether it is used for common polypropylene (PP) plastic welding in automotive manufacturing or polycarbonate (PC) plastic welding in the electronics industry, TH - 200 can accurately measure its laser transmittance.

This instrument is easy to operate and is equipped with an intuitive user interface and automated measurement software. Operators only need to place the plastic sample at the designated position, start the measurement program, and the instrument can quickly complete the measurement and generate detailed data reports. This greatly improves the detection efficiency and is suitable for large-scale detection on production lines. In addition, TH - 200 has good stability and reliability, can operate stably in industrial production environments for a long time, reduces the frequency of equipment maintenance and calibration, and lowers the usage cost.

III. Innovative Application Methods of Laser Transmittance Meter in Plastic Welding Quality Assessment

1.Material screening and evaluation before welding

Before plastic welding, the laser transmittance of different batches of plastic raw materials is tested by using the Color Spectrum Laser Transmittance Tester TH-200. By analyzing the test data, the batches of materials whose laser transmittance meets the requirements of the welding process can be selected, ensuring the consistency and stability of the raw materials. Meanwhile, for cases where different types of plastics need to be welded, TH-200 can assist engineers in choosing plastic material combinations with matching laser transmittance, optimizing the welding process and improving the welding quality. For example, in the welding of automotive interior parts, through the testing by TH-200, selecting appropriate plastic material combinations can effectively reduce welding defects and improve the aesthetics and durability of the interior parts.

2. Real-time Monitoring of Welding Process

Integrate TH - 200 into the plastic welding equipment and monitor the real-time changes of the laser transmittance in the welding area during the welding process. When the welding process parameters fluctuate, such as unstable laser power or changes in welding speed, it will cause abnormal melting and solidification states of the plastic in the welding area, thereby leading to changes in the laser transmittance. TH - 200 can promptly capture these changes and feed back the data to the welding control system. The control system automatically adjusts the welding process parameters based on the feedback data to achieve closed-loop control of the welding process and ensure the stability of the welding quality. For example, on the welding production line of electronic device casings, by monitoring the laser transmittance in real time and adjusting the welding parameters promptly, it can effectively reduce the scrap rate and improve production efficiency.

3. Comprehensive quality inspection after welding

After the welding is completed, the laser transmittance of the welded joint is detected using TH - 200. By comparing the data with the standard data before welding and the real-time data during the welding process, it is possible to determine whether there are defects in the welded joint, such as incomplete penetration, false welding, and pores. For the quality problems detected, the causes can be further analyzed and corresponding improvement measures can be taken. In addition, TH - 200 can also indirectly evaluate the strength of the welded joint. Research shows that there is a certain correlation between the laser transmittance of the welded joint and the welding strength. By establishing a mathematical model of laser transmittance and welding strength, and using the laser transmittance data measured by TH - 200, the strength of the welded joint can be predicted, providing a more comprehensive basis for product quality assessment.

The innovative application of the color spectrum laser transmittance instrument TH - 200 in the quality assessment of plastic welding brings a new quality control method to the plastic welding industry. Through material screening before welding, real-time monitoring during the welding process, and quality detection and assessment after welding, TH - 200 can effectively improve the quality of plastic welding, reduce production costs, and enhance production efficiency. With the continuous improvement of product quality requirements in the manufacturing industry, the application prospects of laser transmittance instruments in the plastic welding field will be even broader. It will continue to promote the development of plastic welding technology and provide strong support for product innovation and quality improvement in various industries.