Modeling of Preload Bolted Flange Connection Structure for Loosening Analysis and Detection

Figure 25

Acceleration signal EMD decomposition and frequency response curves of 6 bolts’ flange structure under 1500 N impact load. (a) Tightening preload of 5000 N. (b) Tightening preload of 5000 N with one bolt loosened to 3000 N. (c) Tightening preload of 5000 N with one bolt loosened to 300 N. (d) Tightening preload of 5000 N with two adjacent bolts loosened to 300 N.

(a)

(b)

(c)

(d)