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during the operation under maximum loading of 2 tones. Lower line represents the stress
values on the palette, and the upper line represents the stress on the neck of the right
shackle in lover row (Fig. 6.20, Fig. 21).
Figure 6.18. The positions of the gauges
Figure 6.19. Fractured shackle
S
t
r
e
s
s
Figure 6.20: Dynamic stress on the shackle and the
palette
kN/cm
2
Figure 6.21: First impulse of one cycle,
stress
kN/cm
2
The stress of 15 kN/ cm
2
in dynamic test,at the beginning of loading impulse, was
found in the middle of the shackle and the maximum stress was six times higher (90
kN/cm
2)
. In tensile test of shackle sample ultimate tensile stressof 100 kN/cm
2
was found.
After performed analysis and redesign of critical elements, new chain was produced
and built-in. Redesigned chain is presented in Fig. 62. It is in successful exploitation for
satisfactory long time.