In the automotive industry with laser welding technology early and has achieved mass production of the plate for the range of laser Welding Electrode Material. Soudronic Automotive Systems, Inc. (hereinafter referred to as "Soudronic") Department of the world's leading laser welding equipment and system suppliers. According to statistics, in 2004 the global production of tailored blanks for the 180 million expected in 2005 will increase rose to 250 million. As the laser weld quality tailor welded blanks for particularly demanding, therefore, Soudronic earlier developed a laser-based optical imaging and sensing technology for tailor welded blank weld quality control of the first generation of online real-time monitoring system, and the system applied to the laser welding equipment and laser welded pipe equipment. The system uses greatly improved Soudronic in the field of laser welding technology, competitiveness, with TWB suppliers and car manufacturers continue to exchange, Soudronic developed a new generation of more simple and reliable visual seam quality testing system - "SOUVIS (r) 5000" (SOUdronic VIsion System). As the double-edge technical features of the system unique and outstanding detection performance can be widely used in automobile manufacturing industry, laser welding, laser welding, such as car body in white and laser brazing and fuel injection systems and transmission gear welding.
Welding process and its technical limitations
In industrial applications, the laser welding process control is critical, mainly because:
The accuracy of the workpiece to be welded, welded workpiece clamping accuracy positioning and repeat a certain limit, the gap before welding must be controlled within a certain accuracy; for some form of surface welding, laser welding focal point to track the trajectory of the gap (length up to 2m above) the accuracy of laser beam diameter does not exceed 10%; sometimes have to be welded metal surface coating (eg galvanized steel), (tag: tungsten wire cutter) and the metal coating due to its low melting point materials are often resulting weld porosity. Mass production in automotive industry applications, laser welding and more use of "deep welded" or "transparent welding" process. However, even on the seam gap control, no matter how, it can not avoid welding defects. From the surface, the laser engraving machine can weld defects, mainly divided into two categories: surface defects and weld geometry of random defects, the former general observation by a weld can be found, which point out that the unpredictable position of local defects.
"SOUVIS (r) 5000" The image processing system
"SOUVIS (r) 5000" The hardware platform is a powerful industrial PC with built-in image processing system with real-time operating system. Sensor head for a CMOS camera, camera features and special adaptive feedback flash technology. The system can be integrated into the TCP / IP network for data exchange, but also by bus (CAN, INTERBUS) connected to the PLC for external control. The system can also connect with a remote server, remote quality control and system failure self-diagnosis. Image processing computer system can achieve direct control of some functions (I / O''s).
Image acquisition
Two other pieces by the laser line projected to be at a certain angle to get onto the weld seam detection of three-dimensional data, that the weld surface geometry data. In a flash device while continuing 20μs instant flash, CMOS camera shot of the weld zone to be detected duplex photos. The two ways to obtain the maximum contrast in the image, the camera features both adaptive optics can also be set using special software, so the system eventually obtain a single image to be detected in the weld zone is reflected in all of the information . System to obtain the standard image size of 10 mm × 10 mm, a resolution of 10μm. In the actual production process, the sensor head or to be detected in a continuous movement of the workpiece to be taken as the system as the trigger device can take to ensure a continuous take, like the two adjacent images have some overlap, in order to achieve continuous take, like testing. Limited by the speed camera and take as data transmission speed, the system detects the speed of 30m/min. Because the system and take the test as fast, so in practice, affect the detection rate of the bottleneck is often the other production equipment, such as welding robots, workpiece shuttle devices.
Feature extraction analysis of weld
Laser welding of weld quality testing depends primarily on two data characteristics: surface of the weld geometry measurements and the absolute uniformity of the weld surface. Weld seam strength of local defects and the surface will affect the visual appearance, therefore, "SOUVIS (r) 5000" use the following three ways simultaneously detect local defects weld: weld-shaped surface three-dimensional data analysis, the organizational structure of the weld analysis and pinhole analysis.
The organizational structure of the weld through a decisive general, random, non-homogeneous fibrous structure to reflect that "fish-bone-shaped" structure. In order to analyze the structure of the weld, the slope of the system based on fiber structure, direction and multi-pixel approach to generate the  Welding Electrodes Manufacturers In China. These structural features can be just a handful of figures to reflect the quality of the weld surface uniformity and smoothness characteristics. If the weld zone in each of these structural features of the data vary widely, then a partial seam weld defects, such as protection because the plasma caused by melting or burning less depth because the surface coating or weld porosity caused by pit. Small weld defects (such as pinholes) can not be detected by this method, therefore, the system uses the first three kinds of analysis algorithms to detect less than a few hundred μm, small welding defects, such as laser-brazing weld in diameter on the detection of only 200μm pinhole, this method is known as the pinhole analysis.
Conclusion
Welding quality with simultaneous visual monitoring in the field of 10 years of experience, Soudronic developed a unique technology, "SOUVIS (r) 5000" weld quality on-line real-time monitoring system for the detection of laser brazing welding or laser weld quality . As a result of high-resolution laser sensor with the μm-level access as technology, the system has excellent detection and resolution capabilities. The whole system integrated in a single unit, to facilitate its installation on the welding equipment, and through a remote server system fault diagnosis. (Tag: seamless pipe) the online real-time monitoring system has a user-friendly, requires less set the parameters, simple operation, etc., while the system hardware rugged shop environment can fully meet the three classes of continuous production.