scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Finite Element Based Member Stiffness Evaluation of Axisymmetric Bolted Joints

01 Jan 2009-Journal of Mechanical Design (American Society of Mechanical Engineers)-Vol. 131, Iss: 1, pp 011012
TL;DR: In this paper, a linear elastic axisymmetric finite element analysis was performed to evaluate the member stiffness, and the results obtained are compared with the results available in the literature, and wide ranges of bolt sizes, joint thicknesses and material properties were considered in the analysis to evaluate characteristic behavior of member stiffness.
Abstract: For a reliable design of bolted joints, it is necessary to evaluate the actual fraction of the external load transmitted through the bolt. The stiffness of the bolt and the member of the joint decide the fractions of external load shared by the bolt and the member. Bolt stiffness can be evaluated simply by assuming the load flow to be uniform across the thickness and the deformation is homogeneous. Then, bolt may be modeled as a tension member and the stiffness can be easily evaluated. But, the evaluation of the member stiffness is difficult because of the heterogeneous deformation. In the present work, joint materials are assumed to be isotropic and homogeneous, and linear elastic axisymmetric finite element analysis was performed to evaluate the member stiffness. Uniform displacement and uniform pressure assumptions are employed in idealizing the boundary conditions. Wide ranges of bolt sizes, joint thicknesses, and material properties are considered in the analysis to evaluate characteristic behavior of member stiffness. Empirical formulas for the member stiffness evaluation are proposed using dimensionless parameters. The results obtained are compared with the results available in the literature.
Citations
More filters
Journal ArticleDOI
TL;DR: In this article, a joint modeling method based on the principle that the basic characteristic parameters of the joints equal the material strain energy is presented. And the results show that the virtual material model can provide a theoretical basis for the accurate joint modeling.

29 citations

Proceedings ArticleDOI
12 Apr 2010
TL;DR: In this paper, the authors exploit finite element predictions for the dierential thermal expansion problem to provide estimates of geometric quantities uncontaminated by the prying action introduced by external forces and then use these accurately determined eective quantities to make hand predictions of bolt force in a ange joint under combined external loading and temperature changes.
Abstract: Accurate calculation of bolt force in a bolted joint under external loads and temperature changes is a fundamental requirement in many industries. Approximate hand formulas, based on idealized mechanical models, are widely used. We evaluate the accuracy of several hand formulas by investigating the consistency of the underlying models and by comparing hand predictions to detailed nite element results. We exploit nite element predictions for the dierential thermal expansion problem to provide estimates of eective geometric quantities uncontaminated by the prying action introduced by external forces. We then use these accurately determined eective quantities to make hand predictions of bolt force in a ange joint under combined external loading and temperature changes. We compare these hand predictions to results from a second detailed nite element model of the ange joint. Finally, we use the ange joint model to gain insight into the joint softening that arises from gradual, nonlinear opening of the ange gap under external tension.

15 citations

Journal ArticleDOI
TL;DR: In this article, a three-dimensional finite element model of the bolted joints is established using the software ANSYS, and pretension force and contact between the joint components are accommodated in the model.
Abstract: Quantitative characterization of contact pressure distribution in bolted joints directly influences the calculation accuracy of connection stiffness. In this paper, a three-dimensional finite element model of the bolted joints is established using the software ANSYS, and pretension force and contact between the joint components are accommodated in the model. Then, parametric studies are carried out to investigate the effects of the material properties, preloads, bolt sizes, grip lengths and hole clearances on the contact pressure distribution. According to the finite element analysis results, a polynomial equation system is derived for mathematical representation of contact pressure distribution in bolted joints. Furthermore, the conical envelope angle used in the mathematical characterization is identified for the bolted joints with different bolt sizes and grip lengths. Finally, an experimental platform is constructed for the measurement of contact pressure distribution, and then the applicability of mathematical characterization is validated by comparison with a series of experiment results.

12 citations

Proceedings ArticleDOI
Yang Guoqing1, Jun Hong1, Ning Wang1, Linbo Zhu1, Yucheng Ding1, Zhaohui Yang1 
25 May 2011
TL;DR: In this article, the deformation mechanism of bolted members and the characterization of the interface contact conditions were investigated. But the authors focused on the performance of bolted joints and did not consider the impact of the stiffness of the members on the bearing and transferring of the initial preload and the operating force.
Abstract: Bolted joints including bolts and members act like elastic springs under assembly and operating conditions. The bearing and transferring of the initial preload and the operating force are mainly dependent on the stiffness of both the bolts and their corresponding members. To obtain the deformation mechanism of bolted members, a systematic study on the prediction of the member stiffness and the characterization of the interface contact conditions is developed in this paper. Firstly, a parameterization process is performed to relate all the geometric dimensions of each bolted joint with the corresponding bolt diameter, so the corresponding dimensionless dimensions can be conveniently gotten by dividing the dimensions by the bolt diameter. Based on this, a novel and efficient finite element (FE) model is constructed to simulate the behaviors of bolted joints with different geometrical sizes and material properties. After characterizing the member stiffness, the interface contact characteristics of bolted joints including contact pressure and the dimensionless contact diameter are further identified through special FE post-processing efforts. Finally, a series of semi-apex angles are obtained through an inverse calculation approach in which an author-modified empirical formula is adopted. The calculation results based on the proposed method may be considered as a simple and practical guideline for the design and assembly processes of bolted joints.

10 citations


Cites background or methods from "Finite Element Based Member Stiffne..."

  • ...853MN/mm, which is between the maximum limit and the reference value in [11]....

    [...]

  • ...Sethuraman [11] employed uniform displacement and uniform pressure assumptions at the bolt head or nut interface according to rigid and soft bolts respectively....

    [...]

Journal ArticleDOI
TL;DR: In this article, a new method for calculating the stiffness of bolted joints is presented, and the effect of joint surface stiffness on the overall stiffness is considered; the results show that the theoretical model presented in this paper is more practical.
Abstract: At present, few scholars have studied the effect of surface roughness on assembly stiffness. The influence of the joint surface stiffness on the overall stiffness is neglected. In this paper, a new method for calculating the stiffness of bolted joints is presented. The effect of joint surface stiffness on the overall stiffness is considered. Firstly, the relationship between load and displacement between cylinder and cylinder (including the joint surface with certain roughness) is studied, and the stiffness characteristic expression of the joint surface is obtained; the results are compared with the traditional stiffness calculation theory, and then, the influence of bolt connection surface on bolt connection is studied and compared with the stiffness calculation results of traditional bolt connection. The results show that the theoretical model presented in this paper is more practical.

7 citations


Cites methods from "Finite Element Based Member Stiffne..."

  • ...Sethuraman and Kumar [15] used the finite element method to analyze the bolts in two different ways and fitted the stiffness calculation formula....

    [...]

References
More filters
Book
02 Aug 2001
TL;DR: In this paper, the authors discuss failure prevention of failure due to static loading and fatigue failure resulting from variable loading in the design of non-permanent joint components, such as screw heads, fasteners, and nonpermanent joints.
Abstract: Part I Basics1 Introduction2 Statistical Considerations3 Materials4 Load and Stress Analysis5 Deflection and StiffnessPart II Failure Prevention6 Failures Resulting from Static Loading7 Fatigue Failure Resulting from Variable LoadingPart III Design of Mechanical Elements8 Screws, Fasteners, and the Design of Nonpermanent Joints9 Welding, Brazing, Bonding, and the Design of Permanent Joints10 Mechanical Springs11 Rolling-Contact Bearings12 Lubrication and Journal Bearings13 Gears - General14 Spur and Helical Gears15 Bevel and Worm Gears16 Clutches, Brakes, Couplings and Flywheels17 Flexible Mechanical Elements18 Shafts and AxlesA Appendix A Useful TablesB Appendix B Solutions to Selected ProblemsIndex

2,781 citations

Book
01 Jan 1981
TL;DR: In this article, the authors introduce the concept of tension and stress in the bolted joint and provide a theoretical analysis of the behavior of the joint under tensile loads and a closer look in-service behavior of a shear joint joint joint failure.
Abstract: Part 1 Introduction to the bolted joint: basic concepts stress and strength considerations threads and their strength materials stiffness and strain considerations. Part 2 Tightening the joint (establishing the clamping force): introduction to assembly torque control of bolt preload torque and turn control stretch control preload control ultrasonic measurement of bolt stretch or tension. Part 3 The joint in service: theoretical behaviour of the joint under tensile loads behaviour of the joint loaded in tension - a closer look in-service behaviour of a shear joint joint failure self loosening fatigue failure corrosion gasketed joints and leaks. Part 4 Using the information: selecting preload for an existing joint design of joints loaded in tension the design of gasketed joints the design of joints loaded in shear.

421 citations

Journal ArticleDOI
TL;DR: In this paper, the authors introduce the concept of tension and stress in the bolted joint and provide a theoretical analysis of the behavior of the joint under tensile loads and a closer look in-service behavior of a shear joint joint joint failure.
Abstract: Part 1 Introduction to the bolted joint: basic concepts stress and strength considerations threads and their strength materials stiffness and strain considerations. Part 2 Tightening the joint (establishing the clamping force): introduction to assembly torque control of bolt preload torque and turn control stretch control preload control ultrasonic measurement of bolt stretch or tension. Part 3 The joint in service: theoretical behaviour of the joint under tensile loads behaviour of the joint loaded in tension - a closer look in-service behaviour of a shear joint joint failure self loosening fatigue failure corrosion gasketed joints and leaks. Part 4 Using the information: selecting preload for an existing joint design of joints loaded in tension the design of gasketed joints the design of joints loaded in shear.

386 citations

Journal ArticleDOI
TL;DR: This work provides a simple technique for computing the member stiffness in many types of bolted connections by performing finite element analyses for joints having a range of materials and geometries.
Abstract: The member stiffness in a bolted connection has a direct influence upon safe design with regard to both static and fatigue loading, as well as in the prevention of separation in the connection This work provides a simple technique for computing the member stiffness in many types of bolted connections Finite element analyses are performed for joints having a range of materials and geometries, and the results are generalized by nondimensionalization An exponential expression for the stiffness is determined, and the results are compared with those of some of the techniques currently used

79 citations