Cross-Wedge Rolling of Driving Shaft from Titanium Alloy Ti6Al4V

2016 ◽  
Vol 687 ◽  
pp. 125-132 ◽  
Author(s):  
Zbigniew Pater ◽  
Tomasz Bulzak ◽  
Janusz Tomczak

This paper deals with the issue of the helicopter SW4 rear gear driving shaft forming. It was assumed that this shaft will be made from titanium alloy Ti6Al4V and it will be formed by means of cross-wedge rolling technology (CWR). It was also assumed that rolling will be realized in double configuration, which will guarantee axial symmetry of forming forces. The conception of tools guaranteeing the CWR process realization and numerical analysis results verifying the assumed CWR process parameters of the subject shaft were presented. Tests of shaft rolling in laboratory conditions at Lublin University of Technology were made, in the result of which the possibility of forming by means of CWR of a driving shaft, manufactured from titanium alloy Ti6Al4V, of the helicopter SW4 rear gear was verified.

2016 ◽  
Vol 687 ◽  
pp. 141-148 ◽  
Author(s):  
Arkadiusz Tofil ◽  
Janusz Tomczak ◽  
Tomasz Bulzak

Theoretical-experimental results of forging rolling and cross-wedge rolling of stepped shafts forgings from titanium alloy Ti6Al4V are presented in this paper. Theoretical assumptions were based on the results of numerical simulations conducted by means of finite element method with the application of software Simufact Forming. During numerical simulations optimal parameters of the rolling processes were determined in view to possibility of obtaining forgings of assumed quality and stable process course. Experimental verification was conducted in universal forging rolling mill of own design, which allows for realization of such processes as splitting without waste, forging rolling and cross as well as cross-wedge rolling processes. During conducted research influence of the way of rolling on the obtained parts quality and the process force parameters were determined. Complex analysis of the chosen rolling parameters impact on the rolling process course and quality of finished products was made. Conducted research showed that it is possible to roll axi-symmetrical forgings of stepped shafts both in transverse and longitudinal arrangement. However, forgings rolled crosswise are characterized by larger precision than in comparison with semi-finished products in longitudinal arrangement.


2012 ◽  
Vol 57 (4) ◽  
pp. 1239-1246 ◽  
Author(s):  
A. Gontarz ◽  
Z. Pater ◽  
K. Drozdowski

This paper presents the research results of hammer forging process of a plane wheel rim forging from titanium alloy Ti6Al4V. The research works were divided into two stages. The first concerned the theoretical analysis based on numerical simulations of the worked out forging technology. Distributions of temperature, strain, damage criterion according to Cockroft-Latham, material flow kinematics and force parameters were evaluated. It was stated that the danger of overheating and material cracking in the forging does not exist. Large force values present in the process means that problems with tools durability may appear. Satisfactory results of the theoretical analysis provided the basis for conducting the second stage of the research works, that is experimental tests in industrial conditions. After dies making forging tests were made in one Polish forging plants, in which a product of good quality was obtained. Manufactured forgings were free from cracks, shape faults and fulfilled requirements concerning mechanical properties.


2014 ◽  
Vol 622-623 ◽  
pp. 1215-1220
Author(s):  
Jarosław Bartnicki ◽  
Janusz Tomczak ◽  
Zbigniew Pater

This paper presents results of numerical calculations of rolling extrusion process of a toothed shaft made from titanium alloy Ti6Al4V. FEM analysis was conducted applying the software DEFORM 3D for the process chosen technological parameters. The kinematics of metal flow in the area of the formed teeth was analyzed. Distributions of stresses, strains and temperatures during teeth forming were determined. Calculated values of axial and radial forces and moments acting on rotating roll tools allow for designing of tools for experimental verification of the designed forming process.


Metals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1998
Author(s):  
Zhanshuo Peng ◽  
Hongchao Ji ◽  
Xiaomin Huang ◽  
Baoyu Wang ◽  
Wenchao Xiao ◽  
...  

Cross wedge rolling has the advantages of high production efficiency, good product quality, high material utilization, environmental protection, and low cost. It is one of the best processing methods for producing shaft blanks. In this paper, a cross wedge rolling die of TC4 titanium alloy is studied. Based on the Archard wear model, a modified model suitable for cross wedge rolling die wear analysis is derived through finite element simulation. Then, the modified Archard wear model is imported into Deform-3D software for finite element analysis. Orthogonal experimental design is used to combine and analyze different process parameters. Finally, the beetle antennae search (BAS)-genetic algorithm (GA)-back propagation neural network (BPNN) algorithm is used to predict the degree of die wear and to optimize the simulation parameters, which can acquire the process parameters that have the least impact on die wear. The results show that the wear distributions of cross wedge rolling tools is uneven. In general, the most serious areas are basically concentrated in the wedge-shaped inclined plane and rectangular edge lines. The reason is that the tangential force and radial force received by the die are relatively large, which leads to increased wear. Moreover, the temperature change is most severe on the wedge-shaped ridge line. When in contact with the workpiece, the temperature rises sharply, which makes the local temperature rise, the mold hardness decrease, and the wear accelerate. Through response surface method (RSM) analysis, it is concluded that the deformation temperature is the main factor affecting wear depth, followed by the forming angle, and that there is an interaction between the two factors. Finally, the feasibility of the BAS-GA-BP algorithm for optimizing the wear behavior of dies is verified, which provides a new process parameter optimization method for the problem of die wear in the cross wedge rolling process.


Think India ◽  
2019 ◽  
Vol 22 (3) ◽  
pp. 72-83
Author(s):  
Tushar Kadian

Actually, basic needs postulates securing of the elementary conditions of existence to every human being. Despite of the practical and theoretical importance of the subject the greatest irony is non- availability of any universal preliminary definition of the concept of basic needs. Moreover, this becomes the reason for unpredictability of various political programmes aiming at providing basic needs to the people. The shift is necessary for development of this or any other conception. No labour reforms could be made in history till labours were treated as objects. Its only after they were started being treating as subjects, labour unions were allowed to represent themselves in strategy formulations that labour reforms could become a reality. The present research paper highlights the basic needs of Human Rights in life.


2018 ◽  
Vol 11 (2) ◽  
pp. 41-51 ◽  
Author(s):  
I. Ya. Lukasevich

The subject of the research is new tools for business financing using the initial coin offering (ICO) in the context of the development of cryptocurrencies and the blockchain technologies as their basis. The purpose of the work was to analyze the advantages and disadvantages of the ICO in comparison with traditional financial tools as well as prospects, limitations and problems of using digital financial tools. Conclusions are made in relation to possibilities, limitations and application areas of digital business financing tools, particularly in the real sector, taking into account the specifics of the Russian economy and legislation. It is shown that the main problems of using the digital financial tools are related to the economic sphere and caused by the lack of adequate approaches to evaluation of assets as well as the shortage of objective information. The problems and new tasks of corporate finance in the digital economy are defined.


1983 ◽  
Vol 22 (1) ◽  
pp. 57-61
Author(s):  
Shahrukh Rafi Khan

The book under review is a compilation of the author's articles and lectures that highlight the prominent developments in the literature on the subject of Islamic banking and inform the reader of the current state of debate on it. One of the earliest and main contributors to this topic is the author himself. The focus of this review will mainly be on "Economics of Profit-Sharing", which is the title of the fourth chapter of the book and is among his latest contributions. This chapter is a significant contribution as it is the first attempt to formalise the concept of profit sharing into an analytical model and, therefore, demands closer scrutiny. However, in the remaining chapters of the book, the author has drawn attention to some of the fine points made in the literature on this topic. Since some of these points appear to be controversial to me, I will briefly discuss them before moving on to the analytical chapter of the book.


2020 ◽  
Vol 22 (2) ◽  
pp. 1-27
Author(s):  
João Carlos Brum Torres

O artigo tem por objeto o exame de três registros de gritantes e distintos paradoxos na Doutrina do Direito de Kant. Registros feitos em tempos e contextos históricos diferentes por Friedrich Bouterwek, Marcus Willaschek e Balthazar Barbosa Filho. Bouterwek atribuiu a Kant a mais paradoxal das proposições jamais enunciadas por qualquer autor, a de que a mera ideia de soberania deve obrigar-nos a obedecer como a nosso inquestionável senhor a quem quer que se haja estabelecido como tal, sem que caiba indagar quem lhe deu o direito de comandar-nos. Willaschek aponta a incompatibilidade de duas teses centrais da doutrina kantiana: a do caráter externo dos vínculos jurídicos e a da incondicionalidade obrigacional do direito positivo, pois não é possível entender como é possível termo-nos como obrigados por imperativos jurídicos e, ao mesmo, vermo-nos internamente isentados do dever de obedecê-los. O ponto crítico de Balthazar é alegar que não pode haver na filosofia kantiana uma crítica da razão político e jurídica, simplesmente porque o conceito de imputação, base da normatividade própria dessas esferas, pressupõe uma pluralidade de agentes livres que, justamente, só pode ser uma pressuposição, pois nosso acesso à normatividade prática só pode ter lugar em primeira pessoa. No exame a que o artigo submete essas alegações, o artigo argumenta, em objeção à tese de Balthazar, que o caráter universal e categórico da força que vincula o sujeito quando confrontado com a lei moral em primeira pessoa necessariamente se desvaneceria se, ao mesmo tempo, ele não fosse tomado pela evidência de que a realidade objetiva dos princípios morais é não só instanciável, mas assegurada pela múltipla instanciação. Com relação às dificuldades levantadas por Willaschek e Bouterwek, o artigo argumenta que o princípio exeundum e statu naturali, enquanto norma metapositiva, anterior à divisão do domínio prático entre doutrina do direito e doutrina da virtude, permite ao mesmo tempo compreender a exigência de obediência ao poder constituído e a restrição das obrigações jurídico-políticas exclusivamente ao foro externo.AbstractThe object of the article is to examine three claims about three distinct and allegedly blatant paradoxes in Kant's Doctrine of Right. These three critical points had been made in distinct times and contexts by Friedrich Bouterwek, Marcus Willaschek e Balthazar Barbosa Filho. Bouterwek attributed to Kant the most paradoxical of all paradoxical propositions, the statement that by the mere idea of sovereignty we are obliged to obey as our lord who has imposed himself upon us, without questioning from where he got such right. Willaschek points out the incompatibility of two main theses of Kantian doctrine of right: the claims that the legal bounds are of external character and that they are the source of unconditional obligations, since it seems impossible to understand how it would be possible to be obliged by juridical norms and decisions and at the same time to be exempted of the internal duty of compliance. The radical objection of Professor Balthazar is the claim that in the context of Kantian Philosophy it is impossible to admit a critique of the juridical and political reason because the concept of imputation, ground of the normativity in these domains, requires not only the presupposition of free agents, but a true and secure epistemic access to them, which is, according to him, impossible considering that the moral law and the other practical principles are accessible for us only in the first person. In the course of the appraisal of such claims, the article contest that objection arguing that the universal and categorical force of the normative bound experienced by the subject when confronted with the moral law in the first person would ineluctably vanish if, at the same time, he had not been taken by the evidence that the objective reality of the moral principles is secured by multiple instancing. Regarding the difficulties raised by Willaschek and Bouterwek, the article argues that the principle exeundum e statu naturali, as a norm of meta-positive character, prior to the division of practical domains between the doctrine of right and the doctrine of virtue, is the cue both to the understanding of the requirement of unquestioning obedience to the constituted power and to the restriction of the validity of this requirement only in foro externo.


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