The Friction Characteristics on the Loosening of Bolted Joints

볼트 결합부 풀림에 관한 마찰 특성

  • Park, Tae-Won (Department of Automobile, Jeonju Technical College) ;
  • Shin, Gwi-Su (Chonbuk National University Automobile Research Institute) ;
  • Jiang, Yanyao (Department of Mechanical Engineering, University of Nevada, Reno)
  • 박태원 (전주공업대학 자동차과) ;
  • 신귀수 (전북대학교 자동차산학협력원) ;
  • Published : 2004.03.01


By using an experimental approach recently developed to determine the torque-tension relationship for bearing frictional characteristics of several typical bolted joints were studied. The experimental approach allows the direct determination of the bearing friction between the nut and its bearing surface. Detailed friction studies were made on the influences of the size and shape of the hole, the use of a slot in a bolted joint, contact area and position, and other factors such as turning speed, coating, and the use of wax on the bearing surface. The contact area and position of the washer have a marginal effect on the bearing friction. The organic coating on the nuts reduces the bearing friction significantly. Nuts with organic coating over a washer with zinc finish provide the smallest and the most consistent bearing friction. The results from the experimental investigation will be helpful for the better design of bolted joints bearing friction. The results from the experimental investigation Will be helpful for the better design of bolted joints.


frictional characteristics;bearing friction;contact area and position;washer


  1. T. Sakai, 'The Friction Coefficient of Fasteners', Bulletin of the JSME, Vol. 21, No. 152, Feb., pp. 333-340, 1978
  2. Y. Jiang, J. Chang and C. H. Lee, 'An Experimental Study of the Torque Tension Relationship for Bolted Joints', International Journal of Materials and Product Technology, Vol. 16, pp. 417-429, 2001
  3. T. Fukuoka and T. Takaki, 'Mechanical Behaviors of Bolted Joints during Tightening using Torque Control', JSME International Journal, Series A, Vol. 41, pp. 185-191, 1998
  4. G. H. Junker, 'New Criteria for Self loosening of Fasteners Under Vibration', SAE Paper 690055, pp. 314-335, 1969
  5. M Hagiwara and N. Ohashi, 'A New Tightening Technique for Threaded Fasteners', Transaction of the ASME, Vol. 116, pp. 64-69, 1994
  6. W. Eccles, 'Design Guidelines for Torque Controled Tightening of Bolted Joints', SAE paper No. 930578, 1993
  7. A. Bray and R. Levi, 'Factors Affecting Tightening Characteristics of Bolts', Experimental mechanics, Vol. 6, pp. 409-419, 1966
  8. 박태원, 신귀수, Y. Jiang and Ming Zhang, '보르결합부 풀림에 관한 마찰 특성'. 산업안전학회지, Vol. 18. No. 2, pp. 1-5, 2003