A mathematical model and an experimental procedure are presented to study the self-loosening phenomenon of threaded fasteners that are subjected to cyclic transverse loads. The study investigates the effect of thread pitch, initial bolt tension, and the amplitude of the external excitation on the loosening of a single-bolt joint. The rate of drop in the joint clamp load (fastener tension) per cycle, as well as the total number of cycles that would cause the complete loss of clamp load, are monitored. In the mathematical model, the differential equations of linear and angular motion of the bolt are formulated in terms of the system properties and the external cyclic transverse excitation. Numerical integration of the equation of angular motion provides the bolt rotation in the loosening direction, which causes the partial or full loss of the clamp load. An iterative MATLAB code is developed and used for the calculation of tension loss in the fastener tension due to the self-loosening. Analytical and experimental results are discussed.

1.
Hess
,
D.
, 1998, “Vibration and Shock Induced Loosening,”
Handbook of Bolts and Bolted Joints
,”
J. H.
Bickford
,
S.
Nassar
, eds.,
Marcel Dekker
, New York, pp.
757
824
.
2.
Sakai
,
T.
, 1978, “
Investigations of Bolt Loosening Mechanisms
,” 1st Report, On Bolts of Transversely Loaded Joints,
Bull. JSME
0021-3764,
21
, pp.
1385
1390
.
3.
Haviland
,
G. S.
, 1983, “
Designing With Threaded Fasteners
,”
Mech. Eng. (Am. Soc. Mech. Eng.)
0025-6501,
105
, pp.
17
31
.
4.
Yamamoto
,
A.
, and
Kasei
,
S.
, 1984, “
A Solution for the Self-Loosening Mechanism of Threaded Fasteners Under Transverse Vibration
,”
Bull. JSME
0021-3764,
18
, pp.
261
266
.
5.
Tanaka
,
M.
,
Hongo
,
K.
, and
Asaba
,
E.
, 1982, “
Finite Element Analysis of the Threaded Connections Subjected to External Loads
,”
Bull. JSME
0021-3764,
25
, pp.
291
298
.
6.
Vinogradov
,
O.
, and
Haung
,
X.
, 1989, “
On A High Frequency Mechanism of Self-Loosening of Fasteners
,”
Proceedings of 12th ASME Conference on Mechanical Vibration and Noise, Montreal
, ASME, New York, pp.
131
137
.
7.
Zadoks
,
R. I.
, and
Yu
,
X.
, 1993, “
A Preliminary Study of the Self-Loosening in Bolted Connections
,” ASME Nonlinear Vibrations, ASME Vol. DE-Vol. 54,
79
88
.
8.
Zadoks
,
R. I.
, and
Yu
,
X.
, 1997, “
An Investigation of the Self-Loosening Behavior of Bolts Under Transverse Vibrations
,”
J. Sound Vib.
0022-460X,
208
, pp.
189
209
.
9.
Junker
,
G. H.
, 1969, “
New Criteria for Self-Loosening of Fasteners Under Vibration
,”
SAE Trans.
0096-736X,
78
, pp.
314
335
.
10.
Nassar
,
S. A.
,
El-Khiamy
,
H.
,
Barber
,
G. C.
,
Zou
,
Q.
, and
Sun
,
T. S.
, 2005, “
An Experimental Study of Bearing and Thread Friction in Fasteners
,”
ASME J. Tribol.
0742-4787,
127
, pp.
263
272
.
11.
Steidel
,
R. F.
, 1989,
An Introduction to Mechanical Vibrations
,
3rd ed.
,
Wiley
, New York.
12.
Bickford
,
J. H.
, 1997,
An Introduction to the Design and Analysis of Bolted Joints
,
3rd ed.
,
Marcel Dekker
, New York.
13.
Juvinall
,
R. C.
, and
Marshek
,
K. M.
, 2000,
Fundamentals of Machine Component Design
,
3rd ed.
,
Wiley
, New York.
14.
RS Technologies, 2004,
Threaded Fastener Testing System User Manual
,
RS Technologies
, Farmington Hills, MI.
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