MACHINE VISION
SURFACE QUALITY CHECK FOR BEARING BALLS
The Center of Device Development, at the Fraunhofer Institute for Silicate Research, has developed a fully automated checking system for bearing balls. Find out more...
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igh-precision ball bearings need to meet special tribological requirements to ensure their long-term, faultfree performance in drive technology – for example in gearboxes without lubricants. Currently, ceramic ball bearings offer the best technical properties for such applications. Production of the bearing components, and the bearing balls in particular, requires high precision and process reliability. Even the slightest deviation from the optimum shape or the desired surface quality can cause bearing damage and failures. To minimise risk, the Center of Device Development (CeDeD) at
the Fraunhofer Institute for Silicate Research (ISC) has created a fully automated, robot-based inspection system for one bearing ball manufacturer. The Ceramic Ball Check System (CBCS) has been in operation since the beginning of 2019 and its performance largely depends on the built-in machine vision systems. The developers at the Fraunhofer Institute split the complete bearing ball check into two separate units – In the first step, the components’ roundness is checked in accordance with the standards, followed by quality control of the ball surfaces in the second step. The exact feeding of the bearing balls to the respective
testing module, the passing-on of defect-free balls and the ejection of faulty products is carried out by a robot. The required testing speed of the system resulted from the preceding manufacturing process: the developers’ goal for the entire system was 2,000 balls per hour. Besides the requirement for speed, the properties of the ceramic balls posed further challenges for the machine vision system. The surfaces to be measured are highly reflective and require a special illumination system that minimises the reflections in order to solve the various measurement tasks. In addition, the system had to be flexible, as various standardised ball sizes – with
Inspection solution for complex piping The interior of pipelines that carry hazardous material often need to be inspected for corrosion and other defects using videoscopes. However, long and complex piping can be especially difficult to navigate and inspect due to multiple bends in the pipework and potential obstructions. Olympus believes it can offer a solution to this problem with the IPLEX GAir long videoscope, which is said to combine maneuverability with wide-viewing images to enable fast and accurate long-distance inspections of complex pipe systems. To quickly reach the inspection target the guide head of the videoscope enables it to slide easily through pipe joints while pneumatic articulation provides fine control, even when the 30m insertion tube is
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fully extended. To enable easy inspection, a gravity sensor automatically rotates the onscreen image, regardless of the scope’s orientation, while the insertion length indicator tracks how far the videoscope has been extended. The chosen image sensor, ultra-bright LED illumination and image processing software help to ensure clear wideview images to enable users to see more in a single view. For an even wider view, an optional 220° fish-eye optical tip adaptor is available to show both the pipe’s side wall and forward view at the same time. For dangerous or hazardous
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inspections, such as inside nuclear power plants, it is possible to set up the videoscope and control it remotely from a safe location, up to 100m. The videoscope’s touch screen can be detached from the main unit and positioned up to 5m away, while wireless capabilities makes it easy to share screen images. Control Engineering Europe
