Wyniki wyszukiwania - BazTech

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Comparison of the dynamic riveting process of a rivet with and without a compensator

Szymczyk E., Slawinski G., Jachimowicz J., Derewonko A.

Journal of KONES

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2009

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Vol. 16, No. 4

455-462

EN

The paper deals with the analysis of deformation of a rivet hole in a riveted joint after the manual dynamic riveting process. For many years, riveting remains a traditional and the most popular method ofjoining in aircraft structures. The residual stress and strain state appear at the rivet hole after the riveting process, which improves the joint's fatigue behaviour. The local finite element models are made with Patran. The rivet and sheets are described using eight-noded, three-dimensional brick elements. The riveting tools consist of four-noded, two-dimensional shell elements. Numerical FE simulations of the upsetting process are carried out using the Ls-Dyna code. The contact with friction is defined between the collaborating parts of the specimen. The results of simulations of the dynamic riveting process of a mushroom rivet with and without a compensator are compared in this paper. Hole deformation of the upper and lower sheet, squeezing force, as well as deformations of the rivet head are analysed. The influence of the compensator on strain and displacement states is studied. Simulation shows that some technological factors may have positive influence on the residual stress fields. Using the rivet with a compensator results in a better rivet hole filling capability. The rivet hole displacement in upper and lower sheets are at the same level. Paper also present manual dynamic riveting process of reverse and standard riveting procedure and model of riveted specimen.

2

Comparison of the dynamic riveting process of a rivet with and without a compensator

Szymczyk E., Slawinski G., Jachimowicz J., Derewonko A.

Journal of KONES

|

2009

|

Vol. 16, No. 3

415-422

EN

The paper deals with the analysis of deformation of a rivet hole in a riveted joint after the manual dynamic riveting process. For many years, riveting remains a traditional and the most popular method of joining in aircraft structures. The residual stress and strain state appear at the rivet hole after the riveting process, which improves the joint's fatigue behaviour. The local finite element models are made with Patron. The rivet and sheets are described using eight-noded, three-dimensional brick elements. The riveting tools consist of four-noded, two-dimensional shell elements. Numerical FE simulations of the upsetting process are carried out using the Ls-Dyna code. The contact with friction is defined between the collaborating parts of the specimen. The results of simulations of the dynamic riveting process of a mushroom rivet with and without a compensator are compared in this paper. Hole deformation of the upper and lower sheet, squeezing force, as well as deformations of the rivet head are analysed. The influence of the compensator on strain and displacement states is studied. Simulation shows that some technological factors may have positive influence on the residual stress fields. Using the rivet with a compensator results in a better rivet hole filling capability. The rivet hole displacement in upper and lower sheets are at the same level. Paper also present manual dynamic riveting process ofreverse and standard riveting procedure and model of riveted specimen.

3

Riveting process simulation - upsetting of the mushroom rivet

Szymczyk E., Jachimowicz J., Sławiński G.

Journal of KONES

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2008

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Vol. 15, No. 2

493-502

4

Analysis of residual stress fields in the riveted joint

Szymczyk E., Jachimowicz J., Derewońko A.

Journal of KONES

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2007

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Vol. 14, No. 2

465-473

EN

The riveted joints are critical areas of the aircraft structure. The residual stress and strain state appears at the rivet hole after the riveting process and improves fatigue behaviour of the joint. Numerical FE simulations of the upsetting process are carried out using the MARC code. Three-dimensional numerical models are used to determine the resulting stress and strain fields at the countersunk rivet and around the hole. The contact with friction is defined between the mating parts of the joint. Calculations are carried out in an elastic-plastic range. The influence of the rivet geometry, rivet stiffness and the sheet material model on strain and stress states is studied. Non-destructive testing methods like X-ray diffraction, liquid penetrant inspection and visual detection analysis with a UV lamp are used for validation of numerical results. Comparison between numerical and experimental results gives a satisfactory agreement. Numerical simulations allow investigating the influence of imperfections on the strength of the joint.