PSI - Issue 58

Włodzimierz Dudziński et al. / Procedia Structural Integrity 58 (2024) 54 – 60 W. Dudzi ń ski et al. / Structural Integrity Procedia 00 (2019) 000–000

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damages can be found in scientific publications and popular science source (Alpsten, 2019; Đorđević et al., 2020; Honus et al., 2017; Krejsa, 2014; Misiewicz et al., 2021; Przybyłek et al., 2022; Van Do, 2017). The subject of the article is a defect that occurred in one of the machines belonging to the group of material handling machines and machines used in opencast mining. It is a group of machines characterized by a variety of forms and sizes. The group of these machines includes technical objects with their dead weight from several tons to even several thousand. Examples of machines of this type are shown in the following figures.

Fig. 1. Bucket Wheel Reclaimer 3000TPH.

Fig. 2. Bucket Wheel Excavator KWK-1500.1.

The operational hazard of this type of machinery depends to a large extent on their use and place of operation. Machines used for material handling are mainly exposed to weather factors, substances clumping, collisions with other technical objects, and wear and tear. In the case of mining machines, there are risks associated with mining, such as landslides, non-workable inclusions, etc. Wear and tear can be manifested by fatigue cracks that can occur in the structural nodes or components connecting individual parts of the machine. The second case is described in this article. Fatigue cracks are a big problem in these types of facilities for two main reasons. The first is the expected long service life (Moczko et al., 2022; Rusiński et al., 2016), often exceeding 30 years. The second is that some standards do not include a fatigue case (Moczko et al., 2018) in the design calculation or this case is not properly described. As the many years of experience of the research team shows, this is an erroneous assumption (Grabowski et al., 2021). For such large facilities, this can lead to failures or even disasters.

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Fig. 3. General assembly drawing of a bucket wheel excavator with marked location of the damaged axle (pos. 7).