Fully redesigned – presenting the new CABflex3
Darmstadt, December 2014 – Almost every high-speed balancing and overspeed test facility for compressors, generators or turbines contains a second-generation CABflex system by Schenck RoTec. It is used for analysing the vibrations of rotors and calculating recommendations for correction. The latest version CABflex3 follows in the footsteps of its successful predecessor but is even more powerful and efficient. Making this all possible are an enhanced measuring chain and extended analysis tools, incorporated into a modern, straightforward operating concept.
A great deal of experience is required in order to balance turbine rotors or generators because flexible rotors such as these change their amplitude of vibration according to the rotational speed. Balancing is often a lengthy process, which makes it expensive. A balancing run for a large steam turbine can therefore easily take one day or longer. After all, it does involve setting a mass of up to 300 tonnes in motion.
In order to cause these bladed rotors to revolve, it is first of all necessary to generate a vacuum. In large balancing tunnels, the evacuation process alone takes up to 45 minutes. The rotor is subsequently accelerated inside the facility over a lengthy period of time before being decelerated again after attaining the balancing speed, at which point air can be readmitted to the tunnel. This time-consuming procedure explains why operators wish to keep the number of measuring runs as low as possible.
This is precisely what CABflex3 offers: it measures the vibrations during the balancing run, analyses the data, calculates the influential coefficients and provides correction instructions. It thus significantly simplifies and accelerates the complex high-speed balancing operation and reduces the balancing process to a few runs.
In addition to many technical improvements, CABflex3 provides an extensively redesigned operating concept, leading to an increase in efficiency for the balancing process. Clear, interactive graphics combined with a logical navigation structure enable work to be conducted quickly and safely with the software.
CABflex3 also boasts some very useful functional extensions, such as online evaluation. Measurement and analysis no longer take place separately but run simultaneously in real time. This saves the user time during the entire process.
The software from Schenck RoTec calculates the influential coefficients from the measuring runs, and then uses them to produce the correction instructions. During the process, the forecasting tool makes it possible to investigate and assess the theoretically expected improvements from various influential factors. The user can thus draw conclusions about the vibration response of the rotor.
To summarize, it may be stated that CABflex3 further improves efficiency in the high-speed balancing of flexible rotors. It will also be setting the standard for balancing and overspeed test facilities in the future.