The final task deals with the hysteresis and loosening of torsion bar springs depending on the presetting and the method of manufacturing torsion springs. Hysteresis and relaxation were considered for two different methods of making torsion springs, namely method A, where after rolling the spring was presetted to the final value, and method B, where after grinding the spring was partially presetted, then rolled and again presetted to the final value.
Experimentally in hysteresis we found that the heat generation in springs made by method A was higher than in those made by method B.
When the springs were loosened, we found that those springs according to method B had a twice as large drop in torsional moment as springs made according to method A.
To ensure optimal torsion springs, we need to have as little presetting as possible, as well as to use spring manufacturing procedures according to method A, because it allows us less loosening on the torsion bar spring.
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