Lead Twist Analysis according to Daimler Automotive Standard MBN31007-07
The new confovis portal system is developed for a contactless and very precise 3D surface inspection of rotationally symmetric parts like drive shafts. It allows complete lateral scans as well as the evaluation of surface lines. In this respect, an evaluation option is the Daimler spin standard MBN 31007-7.
The confovis Portal System with an axis of rotation measures and analyzes shaft sealing surfaces fast and with very high accuracy. The analysis software MountainsMap® of Digital Surf generates automatically the reports in accordance with the Daimler automotive industry standard MBN 31 007-07 out of the measurement data.
The surface texture of lead structures imprinted on shaft sealing surfaces influences the flow characteristics of fluid in the contact zone between sealing surfaces and lip seals. It has a major impact on seal efficiency and leak-tightness. Lead structures consist of continuous or interrupted threads at an angle of zero or a few arc minutes to the circumference of the axisymmetric sealing surface or, in the case of structures with a higher number of threads, at even larger angles. In addition lower frequency macro lead structures and higher frequency micro lead structures are distinguished. In accordance with the Daimler standard lead structures are measured by obtaining 72 scan lines with a length of 2 mm using a rotation unit.
The confovis Portal System scans a complete surface area instead of single spots points-by-point. In this way it provides a very high scanning speed and reduces processing time for this application significantly. The Portal System integrates high-quality microscope components from Nikon. With a 2.15 mm x 1.4 mm field of view the Nikon objective lens allows to obtain each 2 mm scan line in one single measurement step. Complex “stitching” is no longer necessary. High resolution measurement down to a nanometer is achieved using a Z-positioning piezo actuator.
“The confovis Portal System with MountainsMap® speeds up lead twist analysis by measuring lead structures in five minutes with demonstrated 99% correlation with results obtained by tactile system and then generating the analysis report automatically,” stated Frank Thielert, CEO of confovis. “Automotive component manufacturers using the system get reliable results quickly and cost-efficiently.”