OCTOBER 19-20, 2012 - YMCA University of Science & Technology

Proceedings of the National Conference on
Trends and Advances in Mechanical Engineering,
YMCA University of Science & Technology, Faridabad, Haryana, Oct 19-20, 2012
TABLE 1. SHOWING FEM ANALYSIS RESULTS FOR SPRING -1
SL
NO.
SPECIFICA-
TION
HEIGHT
(mm)
UNCOILING UNRESTRICTED
LOAD (N)
SHEAR
STRESS
(N/mm2)
TURN (Rad)
UNCOILING RE-
STRICTED
LOAD
(N)
SHEAR
STRESS
(N/mm2)
LOAD %
DIFF (N)
SHEAR
STRESS %
DIFF (N/mm2)
1 REBOUND 285 366.859 99.528 0.018 368.37 99.881
2 UNLADEN 225 1325.697 359.659 0.066 1331.154 360.932
3 FULL BUMP 130 3597.724 976.057 0.179 3611.683 979.511
0.41187486
2
0.41163252
2
0.38799529
9
0.354674062
0.353946377
0.353872776
FIG. 9 LOAD vs DEFLECTION GRAPH
7. CONCLUSION
Based on the work, it is established that there is a clear difference between the two cases of spring loading under
static conditions. The load, load rates and stress values are higher for restricted uncoiling springs compared to
unrestricted uncoiling. Both the experimental and FEM analysis results support this claim [7]. The inference is:
1. Failure of the bearing in the suspension strut results in increased load on the spring, which increases the
chances of failure. We also found that the bearing failure is not considered during spring failure analysis.
2. Some testing machines at the facility had a turning test bed already placed on a bearing, while others did not.
Thus, standardization of these testing machines will result in more accurate results on all the machines.
3. During the course of the project, a shackle was designed that can be mounted on the Larson testing machine
and the uncoiling in any compression spring can be measured.
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