Werth TomoScope XS – CT Scanning Technology, in a New Compact Format
In recent years, developments in computed tomography have concentrated on the high-resolution measurement of large workpieces and materials that are difficult to penetrate. To this end, large and heavy coordinate measuring machines were used. X-ray tubes came in two varieties: Closed tubes often need to be replaced after just two or three years, while open X-ray sources require maintenance several times a year. This results in frequent downtime and high maintenance costs.
With the TomoScope® XS, TomoScope technology is now available in a new compact format. The new machine type uniquely combines many advantages of various machine classes. The transmission tube – with a unique monoblock design – produces a small focal spot even at high X-ray power, so that rapid measurements can be performed at high resolution. The new X-ray source combines the advantages of closed and open micro- focus X-ray tubes. The monoblock design combines the source, voltage generator and vacuum pump into a single serviceable unit. This results in both long maintenance intervals and a virtually unlimited service life. Downtime and operating costs are minimized. The maximum X-ray voltage is 130 kV, with an available 160 kV for workpieces with greater radiographic length and denser materials. The air bearing rotary axis positions the workpiece with the highest precision to ensure low measurement uncertainty.
Due to the compact design, the minimal space requirement and low weight of the TomoScope® XS, it can be set up nearly anywhere. Low acquisition and operation costs allow rapid amortization. With the exclusive source design, easy upgrade of the X-ray voltage and power to 160 kV and up to 80 W is possible at the installation site.
Like all Werth CT machines, the TomoScope® XS also reconstructs the workpiece volume in real time, in parallel with capturing the images, allowing the system to be used for production monitoring. The use of WinWerth® measurement software for the overall measurement process enables traceability of the measurement results. Werth Messtechnik is the first and currently the only manufacturer to guarantee reliable and traceable measurement results by calibrating all CT machines according to standards, including DAkkS certification. For the first time, a compact, low-cost machine with specifications according to standards is available. With rapid amortization and low maintenance costs for the new highly accurate tubes, the TomoScope® XS allows CT sensor systems to be used across a wide spectrum of workpieces and tasks within any company.
High Cycle Speeds with OnTheFly CT
One benefit of computed tomography is that the workpiece is captured completely, including un- dercuts and internal geometries. Histori cally, com- puted tomography has been too slow for measurements during the manufacturing process.
For years, real-time reconstruction in Win Werth in parallel with image capture has been used to mini- mize measurement time. To move beyond this, sev – eral methods have been introduced, each with its drawback. For instance, the power level of the X-ray tubes may be increased, but this comes at a cost of lower res olution due to the larger focal spot. The exposure time can also be decreased by reducing the distance between the X-ray source and the de- tector. However, doing this will increase the sever- ity of cone beam artifacts. Directly reducing only the exposure time means that the dynamic range of the detector will not be fully utilized. Finally, it is possible to improve measurement time for a multi- cavity measurement, by measuring several work- pieces simultaneously. This can be done because the point clouds are separated automatically. This method, however, generally limits the magnification, reducing the resolution for each individual part.
The new OnTheFly CT (patent pending) saves time lag due to start-stop positioning of the workpiece by continuously rotating the machine axis. In conventional start-stop operation, the rotary motion is interrupted in order to capture each radiographic image, so that no motion blur occurs under continuous exposure. For OnTheFly CT, short exposure times are needed in order to minimize motion blur. To achieve the same measurement uncertainty as in start-stop operation, the number of rotary increments is increased. The specification according to VDI/VDE is not affected, despite the greatly accelerated measurement process; ensuring traceability of the measurement results with OnTheFly CT is maintained.
With the new OnTheFly process, measurement time can be reduced by up to ten times for the same quality of data. The workpiece volume is reconstructed in real time and is available immediately after measurement. Alternatively, the data quality may be increased for the same measurement time. Methods such as raster and ROI (Region of Interest) tomography or higher detector resolution produce workpiece volumes of higher resolution with a better signal-to-noise ratio. The increased measurement time traditionally associated with these methods can be avoided with OnTheFly CT. The new technology opens up further areas of application for computed tomography that have strict measurement time requirements for a given data quality