Analysis of the effectiveness of solutions to reduce coal mill vibration levels in power plants – case study
Autor
Kozioł, Krzysztof
Stypuła, Krzysztof
Opublikowane w
Builder
Numeracja
18-20
Data wydania
2020
Język
angielski
ISSN
1896-0642
DOI
10.5604/01.3001.0013.8788
Słowa kluczowe
structure dynamic, vibration measurements
Abstrakt
The paper presents case of selected power plant, where substantial increase of displacements of the foundations of the main power unit was observed and an exemplary method of solving such type of problem. The problem concerned both static settlements as well as vibrations. Since the operation of the equipment (coal mill) causes movement difficult to be determined using analytical methods, initially vibration measurements had to be made. As a result, time courses of foundations as well as selected points onto investigated structure accelerations were obtained. The computational model (FEM) was loaded with excitation registered on the foundation, while acceleration time courses obtained in real conditions were used to validate its parameters (material constants of structure and soil) and joints rigidity. After obtaining a satisfactory difference between accelerations (FEM model - real construction), three repair variants were simulated. In two of them the propagation path was separated with an anti-vibration barrier, while in one the stiffness of the soil below foundation was increased. Each of the mentioned solutions reduced the vibration level of the structure in the vicinity of coal mills. Nevertheless, in the case of “covering” foundations with anti-vibration mat, significant increases in vibration matacceleration of mills were observed. It was also pointed out that increasing the soil stiffness below foundations, despite limiting the level of vibration amplitudes in the entire facility, may prove to be troublesome for technological reasons.
