A constructive algorithm to maximize the useful life of a mechanical system subjected to ageing, with non-resuppliable spares parts

The design and simulation of a multifunctional system for the machining of mechanical parts and printing in 3D (x, y, z) using CAD software Solid works, was used to determine the static behavior of the system with the analysis of tension, deformation, displacement, safety factor, buckling, fatigue and frequency. For the above, it was determined that the lateral base supports a tension of 3.5x108Pa, causing a displacement of 25 mm and an equivalent unit strain (ESTRN) of 0.0012. And the base guiding a cumulative damage of 300% of deterioration that reduces its useful life to a range between 1x106and 1x1065utility cycles and a safety factor (F S) between 104.632 to 7869.86. On the other hand, the transverse base has a maximum cumulative damage percentage of4.10535 and a life cycle range ranging from 24358.5 to 1x106with a minimum SF of 5974

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Failure Analysis With the Scanning Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095662 ◽

1972 ◽

Vol 30 ◽

pp. 482-483

Author(s):

John R. Devaney

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Integrated Circuits ◽

Failure Analysis ◽

High Reliability ◽

Military Applications ◽

Small Structure ◽

Useful Life ◽

Insight Into ◽

Scanning Electron

Occasionally in history, an event may occur which has a profound influence on a technology. Such an event occurred when the scanning electron microscope became commercially available to industry in the mid 60's. Semiconductors were being increasingly used in high-reliability space and military applications both because of their small volume but, also, because of their inherent reliability. However, they did fail, both early in life and sometimes in middle or old age. Why they failed and how to prevent failure or prolong “useful life” was a worry which resulted in a blossoming of sophisticated failure analysis laboratories across the country. By 1966, the ability to build small structure integrated circuits was forging well ahead of techniques available to dissect and analyze these same failures. The arrival of the scanning electron microscope gave these analysts a new insight into failure mechanisms.

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Dynamic Modeling and Wear-Based Remaining Useful Life Prediction of High Power Clutch Systems

Tribology Transactions ◽

10.1080/05698190590927451 ◽

2005 ◽

Vol 48 (2) ◽

pp. 208-217 ◽

Cited By ~ 32

Author(s):

Matthew Watson ◽

Carl Byington ◽

Douglas Edwards ◽

Sanket Amin

Keyword(s):

Dynamic Modeling ◽

High Power ◽

Life Prediction ◽

Remaining Useful Life ◽

Useful Life

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Study of the dynamics of ТПА 350 automatic mill working stand elements

Ferrous Metallurgy Bulletin of Scientific Technical and Economic Information ◽

10.32339/0135-5910-2020-8-830-840 ◽

2020 ◽

Vol 76 (8) ◽

pp. 830-840

Author(s):

S. R. Rakhmanov ◽

V. V. Povorotnii

Keyword(s):

Mechanical System ◽

Dynamic Model ◽

Maximum Amplitude ◽

Calculation Scheme ◽

Dynamic Loads ◽

Forced Oscillations ◽

Mass Model ◽

Automatic Mill ◽

Hollow Billet ◽

Oscillation Movement

To form a necessary geometry of a hollow billet to be rolled at a pipe rolling line, stable dynamics of the base equipment of the automatic mill working stand has a practical meaning. Among the forces, acting on its parts and elements, significant by value short-time dynamic loads are the least studied phenomena. These dynamic loads arise during transient interaction of the hollow billet, rollers, mandrel and other mill parts at the forced grip of the hollow billet. Basing of the calculation scheme and dynamic model of the mechanical system of the ТПА 350 automatic mill working stand was accomplished. A mathematical model of dynamics of the system “hollow billet (pipe) – working stand” within accepted calculation scheme and dynamic model of the mechanical system elaborated. Influence of technological load of the rolled hollow billet variation in time was accounted, as well as variation of the mechanical system mass, and rigidity of the ТПА 350 automatic mill working stand. Differential equations of oscillation movement for four-mass model of forked sub-systems of the automatic mill working stand were made up, results of their digital calculation quoted. Dynamic displacement of the stand elements in the inter-roller gap obtained, which enabled to estimate the results of amplitude and frequency characteristics of the branches of the mill rollers setting. It was defined by calculation, that the maximum amplitude of the forced oscillations of elements of the ТПА 350 automatic mill working stand within the inter-roller gap does not exceed 2 mm. It is much higher than the accepted value of adjusting parameters of the deformation center of the ТПА 350 automatic mill. A scheme of comprehensive modernization of the rollers setting in the ТПА 350 automatic mill working stand was proposed. It was shown, that increase of rigidity of rollers setting in the ТПА 350 automatic mill working stand enables to stabilize the amplitude of forced oscillations of the working stand elements within the inter-rollers gap and considerably decrease the induced nonuniform hollow billet wall thickness and increase quality of the rolled pipes at ТПА 350.

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