Bell systems are exposed to high loads during ringing, which can lead to different damage to the individual components. The methods of material testing determine the extent and possible causes of cracks. Typical damage to bells are:
- Fatigue cracks in the sound body
- Material removal and wear at the stop points
- Wear and cracks on clapper eyelets
- Cracks in the area of the bell crown
Typical damage to clappers:
- Fatigue cracks in the area of the shaft
- Cracks on the suspension / on the leather binding
- Wear on the stop points, especially when using stop buffers
Optimization of the ringing conditions
Bell systems are dynamic multi-pendulum systems. In order to achieve optimal ringing conditions for good sound development and protection of the bell, the two pendulum bell (in conjunction with the yoke) and clapper must be dynamically matched.
Using computer models and dynamic simulation tools, the geometric and dynamic properties of the pendulum are designed to match the ringing conditions to the specific conditions of the building and the musical specifications of the possible bells.
With the musical fingerprint of bells, the current state of a bell can be determined. With the help of sound recordings, cracks and imperfections in bells can be detected and localized, even if they are not yet detectable by the eye or if they are inside the bell.
The musical fingerprint is particularly suitable for this:
- to detect cracks that do not yet have an audible effect on the bell sound;
- to monitor endangered, valuable or damaged bells, in order to avoid crack propagation or to detect it at a very early stage;
- to check the quality of a bell repair and to detect possible further damage;
- to monitor repaired bells in order to prevent the possibility of cracking again;