(1) Welding Inspection
The quality inspection and assurance system provides assurance for the production of high quality spliced plates. The production process of spliced plates is carried out using an automated production line in order to ensure safe and economical production, which requires modern inspection instruments. As early as 1985, when ThyssenKrupp Laser Splicing Plates GmbH in Germany started to produce splicing plates, a monitoring system was introduced, which is now even better. A weld seam monitoring system is installed behind the welding laser head and is used to monitor the quality of the weld seam to ensure that it meets the quality requirements. A plasma monitoring system is used to monitor the stability of the welding process, and a computer-aided system can process the signals provided by the sensors during the welding process.
Laser spliced panels require fully automated or semi-automated economical production lines with modern technology to monitor the welding process and product quality. In order to meet the requirements of these new fully automated production processes for the production of randomly spliced panels, ThyssenWelding Technology GmbH, the research department of ThyssenKrupp Steel GmbH, ThyssenKrupp Laser Technology GmbH and ThyssenNobel GmbH proposed different possibilities for the automated evaluation of the quality of the weld seam and the management of the production process in the preliminary phase, and the first laser splicing plate factory that started operation produced the The first laser welded plate from the first laser welded plate factory was used for the base plate of the Audi 100. In recent years, this technology has been further developed and improved in various stages to not only control the welding process itself, but also to evaluate the weld seam with this latest-generation technology, which was developed based on existing systems. Its monitoring system not only monitors defects in the weld seam geometry at high welding speeds, but also detects very small holes.
(2) Evaluation systems
Thyssen LAM (Laser Application Management), in combination with weld seam inspection systems, not only detects tendency defects, such as irregular seam geometry (seam incidence, edge displacement, root sag), but also defects of small magnitude, such as porosity and holes. The combination of light streak and plasma sensor systems has been optimally supplemented so that the high measuring rate guarantees the safe detection of minor defect possibilities at high welding speeds.
A computer-assisted evaluation system automatically evaluates the sensor signals, including during the welding process. This determines whether the conditions at the relevant measuring points meet the specified requirements or whether deviations that cause the quality of the seam to drop have occurred. During the welding process, the temperature of the welded seam is registered by infrared measurements. The sensor data records of the individual spliced panels being evaluated are stored in a short protocol, which means that the quality of the product is allowed to be documented.
A complete error detection system warns the operator of all mechanical shortcomings occurring in the fully automated welding facility, and this quality management and monitoring system has been extended to the new machine concept for non-linear laser welding production. Sensors placed in front of the welding head are able to detect the joining edges of the sheet to be welded, allowing not only the exact position of the joining edges to be identified, but also the measurement of overlaps between sheets. When the identified overlap measurement exceeds a predetermined limit value, the operator is warned and the gap is automatically organized. In addition, with this device, the detection signal of the connection edge is also used to accurately identify and adjust the laser beam of the connection edge.