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Extended analysis of crack behaviour has concluded that the 5 cm crack is not danger-
ous, but from 5 to 13 cm it will grow in a stable manner and beyond 15 cm, an unstable
crack growth may be expected. It is concluded that the furnace can be used with detected
crack of 10.7 cm for the next six months. After this period, measurements have shown
that the crack length has reached 20 cm and further service was not allowed.
3.16. Recovery of the rotary furnace ring
In order to improve the design of the rotary furnace ring in the Cement Factory of
Popovac, model analysis has been performed. The half rotary furnace model is presented
in Fig. 45. The results of stress and thermal loading analysis (
∆
T
= 100°C) are shown in
Fig. 45, and in Table 16.
Dead load effect on deformation (
f
max
= 0.353 cm) and
stress (0–3.5 kN/cm
2
, step 0.5)
Dead and thermal load effect on deformation (
f
max
=
6.72 cm) and stress (0–15 kN/cm
2
, step 1)
Figure 45. Model of the rotary furnace ring with deformation and stress
300