TomoScope® XS – a success story Computed tomography displaces conventional coordinate measuring machines

Before 2017, compact CT machines were only available with reflection target tubes in a closed design. Their large focal spot limited resolution and accuracy due to geometric blurring. Although the machines were relatively inexpensive, they incurred high maintenance costs. The limitation to acceptable focal spot sizes, which were only achieved when the machine was operated at very low power, resulted in high exposure and thus measurement times. Standard-compliant specifications for assessing performance and for comparison with other machines were often lacking.
For large machines, transmission target tubes with up to 300 kV tube voltage enabled high resolution and accuracy. However, they were expensive to purchase and maintain, and because of their size and weight they were mainly used in specially designed measuring rooms.

Werth received many inquiries from customers who found the CT technology highly interesting, but could not economically justify the investment due to the high prices. This fact motivated the Werth development team to think in new directions. The prerequisite for the introduction of a new, more cost-effective machine was the new tube design that resulted from intensive development work. For the new TomoScope® XS, tube, generator and vacuum generation were combined in an open monoblock design. This design allows long maintenance intervals with a virtually unlimited service life, as spare and wear parts can be replaced during annual machine maintenance due to the open design. For the user, this results in short downtimes and low operating costs. Since the new machine has been equipped with a transmission tube, the focal spot size remains small even at high tube power. This is an important advantage of the TomoScope® XS, which thus allows fast measurements with high resolution. The novel X-ray tube was combined with a compact and precise air-bearing rotary axis and a fast detector. In addition, small machine dimensions and a specification of the length measurement error in the lower micrometer range were crucial. Intelligent design solutions made it possible to offer the machine at about the same price level as conventional tactile or multisensory coordinate measuring machines.

With the TomoScope® XS, CT coordinate measuring machines now became affordable for everyone. The high demand could only be met by expanding production capacities.

About one and a half years after the introduction of the TomoScope® XS, it became apparent that some customers would like to use the advantages of the machine in conjunction with a larger measuring range. Therefore, the basic concept was expanded and two additional axes were integrated into the machine. With the measuring range increased fourfold, the new TomoScope® XS Plus achieved a ratio of size and weight to measuring volume that remains unique.
The trend was also in the CT sector increasingly toward measurements during production. For the high cycle rates, the measuring speed of the machines had to be further increased. Werth had already achieved this with the larger TomoScope® FQ machines for in-line measurements of, for example, aluminum die-cast workpieces. The machines are equipped with a high-performance macro-focus tube for fast measurements with high detector resolution. This principle should now be transferred to a new compact machine while meeting even stricter cost requirements.

As a result, the new TomoScope® XS FOV was introduced in 2020 on the proven basis of the TomoScope® XS. The core of the machine concept is a low-cost X-ray tube with a maximum voltage of 130 kV and powers of up to 100 W. This has created probably the most affordable CT coordinate measuring machine on the market, often priced below conventional 3D coordinate measuring machines. The TomoScope® XS FOV is the best solution for all applications where the high resolution of the TomoScope® XS in the single-digit micrometer range is not absolutely necessary.

After the market launch of the TomoScope® XS FOV, many requests also came from the application area of production-accompanying rapid measurement. For this purpose, the TomoScope® XS FOV 500 was equipped with a powerful tube in order to be able to quickly measure and analyze larger and denser workpieces..