Calsonic Kansei Korea's shop floor, where exhaust systems
Calsonic Kansei Korea is a South Korean automobile manufacturer that supplies exhaust systems to Renault Samsung Motors, and was established in 1996 as a joint venture company based on the technology of Calsonic Kansei, a dedicated automotive parts manufacturer in Japan.
The company adopted the one touch changeover system and inline manufacturing concepts and applied it to its manufacturing stages, from parts production to final assembly. This enabled the company to produce automotive parts that can be directly mounted onto a completed car by fastening a couple of bolts via intermediate assembly.
The exhaust systems manufactured by the company adopted a pre-converter and main converter, and its manufacturing processes include applications such as NC pipe bending and a synchronised robot welding system.
CMMs And Hand Measuring Tools
Since its inception, the company has mainly used fixed coordinate measuring machine (CMM) and conventional hand tools, such as vernier callipers, R-gauges, and shape detection tools for quality control. A 2D measuring instrument takes a longer time to measure objects and has proven to be prone to measurement errors.
“It was difficult to measure contour lines or the overall shapes of objects with a fixed CMM, especially when forming iron plates. It was also not easy to inspect shapes with our other tools in the inspection chamber either. One may be able to detect the presence of a gap, but it is difficult to check for its accurate dimensions or other associated data. I have to admit that product reliability can drop considerably in the process,” said the deputy head of the quality assurance team at Calsonic Kansei Korea, elaborating on the challenges his team faced with the existing system.
In a bid to improve its inspection process, the company then decided to tap on an equipment support project offered by the Busan Techno Park, where they came across portable measurement devices.
Making The Jump
3D scan data with measurements
“Our competitors have been using 3D scanning devices for a long time now,” he continued. “Our customers in Europe would demand for 3D scan data whenever they had any issues with the quality. I realised that the overall expectations for quality assurance both in South Korea and in the global market have jumped from 2D practices to 3D instruments.”
The quality assurance team then began the process of procurement for the new measuring device. They selected Faro’s Edge ScanArm ES for its contact-type measurement capabilities as well as its scanning functionalities. The device was suitable for the needs of the company, since the team required 3D scanning for the pressed parts and also carried out contact-type measurements for calibration in the inspection chamber.
The ScanArm ES is a portable 3D articulated measuring device capable of performing measurements either through probing or 3D laser scanning of the target objects. The team revealed that on average, the devices are used around two hours each day, five days a week, excluding weekends. Measuring processes that would have taken nearly a day was now completed within two hours.
Improved Measurement Processes
Calibrating an inspection fixture with a tactile probe
Previously, the inspection process was tedious, as technicians had to cut up products one by one before they could to take any measurements. Furthermore, the team often was unable to use the R-gauge due to the difficulty in obtaining measurements.
Inspection processes changed upon introduction of the new device. The target object could be scanned completely within a time frame of a few minutes. Following that, all of the data, including the measurements, are transmitted to the dedicated software. The 3D modeling data generated was then cut across its cross-section to allow for an immediate confirmation of accurate measurements—whether width, height, roundness, or plane—before being compared with CAD data.
Less Complex Inspections
In the past, a complex inspection process spanning four to five stages had to be performed: first, an inspection with the fixed CMM, followed by first- and second-dimensional inspections of the parts that could not be fully verified in the first inspection stage.
Now, a scan by the measurement device and the 3D modelling data generated within a few minutes allow technicians to arrive at a conclusion much quicker. The inspection, which was previously spread across four or five stages, was reduced to a single-stage operation. As a result, the amount of time and labour associated with the inspection was considerably reduced.
Lessened Measurement Conflicts
Scanning of uneven pressed parts with the 3D laser
Before, it was difficult to pinpoint specific improvement points on welded products in the inspection chamber. Even if the shape of each product was verified in the inspection chamber, it was difficult to identify the extent of its gaps. Consequently, welded products that exceeded the acceptable tolerance range remained undetected on occasion. This issue is now resolved as the 3D measurement device delivers measurements and provides 3D shapes of welded products.
In the case of pressed parts with uneven surfaces, it was difficult to obtain accurate X, Y, and Z coordinates with the fixed CMM. Now, by checking the cross-section of the modelling data generated by the ScanArm ES, measurements of the processed parts’ protrusions can be determined easily.
Field staff could then proceed with a set of accurate measurements instead of the previous rough estimations they had to work with. Such improvements eliminated any misunderstandings or conflicting perspectives.
Streamlined Manufacturing Process
Previously, potential problems would be identified only after the processed parts were put into the manufacturing line. If there was a problem, the supplier of the product would then be notified. In fact, suppliers would achieve a final product that corresponds to the drawing only after multiple iterations.
Now, however, any processed product received from a supplier can be promptly checked for discrepancies via 3D scanning. As there is no need to put them into the production line to obtain feedback, suppliers can now produce moulds that match up with their drawings with greater ease.
APMEN Metrology & Design, Mar 2017