Page 286 - Failure Analysis Case Studies II

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Fig. 5. The fracture appearance of a B type hosepipe.

Fig. 6. Fatigue beach marks.

5. Analysis of hosepipe bursting failures

Fracture analysis shows that hosepipe bursting is caused by fatigue failure, but the characteristics
of failure are different in the inner and outer layers.
In structure, the hosepipe is composed of seven layers (Fig. 9). Steel wire is the main load-
bearing layer. The inside layer was projected from the steel wire by a middle layer and a cotton
layer internal to the steel wire layer. The inner layer was in direct contact with kerosene and carried