Estimation of the life of machine parts in block loading

Bagmutov, V. P.; Савкин, А. Н.

doi:10.3103/s1052618807020185

Cited by 3 publications

(6 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sometimes the case of random external loading is approximated by block loading, estimated with a probabilistic analysis taking into account various models of material damage (Bagmutov and Savkin, 2007). Some papers update the well known linear hypothesis by summing fatigue damage (Guriyev and Savkin, 1975;Troshchenko, 1975;Kogaev et al, 1985) or taking into account the effect of loading background for predicting the durability of machine parts exposed to random loading (Bagmutov and Savkin, 2007).…”

Section: Introductionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

“…Some papers update the well known linear hypothesis by summing fatigue damage (Guriyev and Savkin, 1975;Troshchenko, 1975;Kogaev et al, 1985) or taking into account the effect of loading background for predicting the durability of machine parts exposed to random loading (Bagmutov and Savkin, 2007).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Cumulation of Effects in Calculating the Deterioration of Fatigue Loaded Structures

Jinescu

2011

International Journal of Damage Mechanics

View full text Add to dashboard Cite

It has been introduced and analyzed on literature-based relations that calculating the deterioration produced by cyclic loading with normal stresses can be actually calculated. Based on the principle of critical energy, deterioration has been expressed as a power function. The deteriorations thus calculated can be summed up in order to obtain the cumulated effect of the external loadings. There have been established expressions for the deterioration produced by the action of: a single cyclic stress, several blocks of cyclic stresses with normal and/or shear stresses by taking into consideration the cumulated effect of vibrations and/or corrosion, cracked or crack free structures. The relations refer to both samples as well as to actual structures with stress concentrations. One suggested a procedure as to apply the obtained results to the case of random loading of a structure. The calculation examples show how the article makes use of the relations proposed.

show abstract

Section: Introductionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Cumulation of Effects in Calculating the Deterioration of Fatigue Loaded Structures

Jinescu

2011

International Journal of Damage Mechanics

View full text Add to dashboard Cite

show abstract

“…When the stage of weakening of the metal begins, the parameters of the basic fatigue curve (8), which are used for the prediction of durability, change. This leads, first of all, to a decrease in the initial endurance limit [14,15].…”

mentioning

confidence: 99%

“…We represent the latter by means of schematization of the operational loading as a generalized block loading with separation of the main striking factors in the course of fatigue of the material, i.e., the maximum amplitude stress s a max and the amplitude stress s à in the loading block. For a nonlinear model, the possibilities of the prediction of durability under irregular loading were presented in [8]. The well-known disadvantages of linear models were corrected by changing the ultimate measure of loading D with regard for its programmed character [5] and by evaluating the accumulation of damage on the basis of secondary fatigue curves [9].…”

mentioning

confidence: 99%

Comparative analysis of models of accumulation of dispersed damages in metals under irregular variable loading

Bagmutov

Савкин

2009

Strength Mater

Self Cite

View full text Add to dashboard Cite

We analyze models of summation of fatigue damages under irregular variable loading on the basis of linear and nonlinear interpretation of the damage function. We show the necessity of taking into account the main physicomechanical processes in the metal under cyclic loading, which can improve the accuracy of computations.Keywords: models of summation of fatigue damages, physicomechanical processes, cyclic loading.The demands of engineering practice in designing new and perfecting the existing technical articles that work under regular and irregular variable loading, as well as the introduction of new promising materials, require the development of models and computational methods that would enable one to better predict the durability of an engineering object under in-service conditions for guaranteeing its high reliability and competitiveness [1,2]. In doing so, it is important both to carry out a comparative analysis of existing models and to develop new models (especially those available for engineering practice) with regard for the actual mechanisms of damage accumulation, improving the accuracy of prediction.The solution of such a complex problem is connected with searching for the most general laws describing the kinetics of damage accumulation in metals. Note that the intention to take into account the phenomena occurring in the structure of metals more accurately leads to the complication of the existing relations. One of the approaches in the theory of summation of fatigue damages is the concept of crack initiation and growth, which has found its reflection in the models of summation where fatigue consists of two stages.The first of them, i.e., the stage of crack initiation, or the development of dispersed damages, is connected with the kinetics of accumulation of microplastic strains, which lead to the development of damages in the form of short dispersed cracks. When the critical point is achieved, the process of damage passes to the second stage, namely, the propagation and growth of a main crack, which, upon reaching its critical length, leads to the fracture of the material or of the structural element. According to another approach, a defect in the form of a crack can always be present in the structure of a metal, especially in the case of stress concentration, and, therefore, one should consider durability as the survivability of a cracked structure, whose lifetime is determined by the kinetics of crack propagation up to reaching its critical size. Such a concept is appropriate for structural elements in operation, especially for preventive measures and for the determination of their lifetime resource. Depending on operational, technological, and design factors, this stage can constitute 10 to 30% of the lifetime of the structure [3].In the present work, we consider the problem of evaluating the durability of materials and structural elements in the stage of dispersed damages (the stage that determines the main lifetime of the structure under consideration up to its failure). In engineering practic...

show abstract

Computer technology of the thermal stress state and fatigue life analysis of turbine engine exhaust support frames

et al. 2019

View full text Add to dashboard Cite

An advanced computer technology of the thermal stress state and fatigue life analysis of turbine engine exhaust support frames based on the use of licensed engineering analysis software, as well as some specialized home codes are presented in the paper. The developed technology allows perform simulations for the full model of the structure, not only for the typical fragments models, and increase an accuracy of calculations and significantly reduce a design time.

show abstract

Estimation of the life of machine parts in block loading

Cited by 3 publications

References 1 publication

Cumulation of Effects in Calculating the Deterioration of Fatigue Loaded Structures

Cumulation of Effects in Calculating the Deterioration of Fatigue Loaded Structures

Comparative analysis of models of accumulation of dispersed damages in metals under irregular variable loading

Computer technology of the thermal stress state and fatigue life analysis of turbine engine exhaust support frames

Contact Info

Product

Resources

About