Numerical analysis and experimental trial of axial feed skew rolling for forming bars

Due to the instable conditions caused by the wear of rollers, macro voids inevitably occur in skew rolling steel balls. Macro voids in rolled balls greatly weakens the mechanical properties, resulting in the scrapping of about 23% of all skew rolling balls. This paper adopts the floating-pressure method (FPM) to eliminate macro voids in rolled steel balls, and mainly focuses on the investigation of the influencing factor void closure in skew-rolled balls. The research contents are listed as follows: Firstly, the mechanical model of FPM eliminating void in rolled steel balls is established, and the theoretical relationship between influencing factors of void closure is obtained. Then, the metal flow behaviors, the stress distribution and the effect of process parameters on void closure are revealed by numerical analysis. Subsequently, based on the uniform design method, the prediction equation of the required temperature and air pressure for compacting various inferior rolled balls with different diameter by FPM is deduced. Finally, the FPM experiment is carried out to verify the results of numerical analysis. The research results provide theoretical guidance for eliminating macro voids in skew-rolled steel balls.

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Numerical Analysis of a Skew Rolling Process for Producing a Stepped Hollow Shaft Made of Titanium Alloy Ti6Al4V

Archives of Metallurgy and Materials ◽

10.1515/amm-2016-0115 ◽

2016 ◽

Vol 61 (2) ◽

pp. 677-682 ◽

Cited By ~ 4

Author(s):

Z. Pater ◽

T. Bulzak ◽

J. Tomczak

Keyword(s):

Numerical Analysis ◽

Thickness Distribution ◽

Effective Strain ◽

Rolling Process ◽

Forming Process ◽

Hollow Shaft ◽

Wall Thickness Distribution ◽

Light Trucks ◽

Titanium Alloy Ti6al4v ◽

Skew Rolling

Abstract The paper describes a rolling process for a hollow Ti6Al4V alloy shaft used in driving systems of light trucks. The shaft is formed by skew rolling using three tapered rolls. The principle of this forming process was discussed stressing its universality due to the potential of applying it for forming various products by one set of rolls. The numerical analysis results (product shape progression in rolling, wall thickness distribution, effective strain, temperature and variations in loads and torques) confirm that the proposed technique can be used for producing hollow long shafts.

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Numerical analysis of a skew rolling process for producing a crankshaft preform

Open Engineering ◽

10.1515/eng-2016-0087 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 7

Author(s):

Konrad Lis ◽

Łukasz Wójcik ◽

Zbigniew Pater

Keyword(s):

Numerical Modeling ◽

Numerical Analysis ◽

Cross Section ◽

Rolling Process ◽

Damage Function ◽

New Method ◽

Rolling Technique ◽

Rolling Method ◽

Skew Rolling

Abstract The paper describes a new method for forming a crankshaft preform. The method is based on the skew rolling technique. With this method the part is formed by three tapered rolls rotated with the same velocity and in the same direction. Simultaneously, the rolls either converge or diverge depending on the desired cross section of the product. The numerical modeling enabled determination of the distributions of effective strains, temperatures, and damage function according to the Cockroft - Latham criterion, aswell as variations in the loads and torques during rolling. The results confirm that a crankshaft preform can be formed by the proposed skew rolling method.

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Skrew Rolling of Balls in Multiple Helical Impressions

Archives of Metallurgy and Materials ◽

10.2478/amm-2013-0128 ◽

2013 ◽

Vol 58 (4) ◽

pp. 1071-1076 ◽

Cited By ~ 8

Author(s):

J. Tomczak ◽

Z. Pater ◽

J. Bartnicki

Keyword(s):

Finite Element Method ◽

Thermal Analysis ◽

Finite Element ◽

Numerical Analysis ◽

Experimental Research ◽

Three Dimensional ◽

Rolling Process ◽

Skew Rolling ◽

Made In ◽

Complex Thermal Analysis

Abstract This paper presents results of theoretical and experimental research on skew rolling process of balls with diameter ;30 mm in multiple helical tools. Numerical analysis of the process was conducted basing on finite element method (FEM), using the commercial software Simufact Forming in version 10.0. Simulations were made in the three-dimensional state of strain with consideration of complex thermal analysis, due to which progression of the products shape was determined. Distributions of strains and temperatures as well as the process force parameters were also determined. The results of numerical calculations were experimentally verified in laboratory conditions. The obtained results confirmed the possibility of semi-finished products of balls type manufacturing by means of rolling in multiple helical impressions.

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Analysis of the Aluminum Bars in Three-High Skew Rolling Mill Rolling Process

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.220-221.892 ◽

2015 ◽

Vol 220-221 ◽

pp. 892-897 ◽

Cited By ~ 2

Author(s):

Andrzej Stefanik ◽

Piotr Szota ◽

Sebastian Mróz ◽

Henryk Dyja

Keyword(s):

Temperature Distribution ◽

Numerical Analysis ◽

Software Package ◽

Rolling Mill ◽

Rolling Process ◽

Theoretical Research ◽

Laboratory Research ◽

Modern Methods ◽

Skew Rolling ◽

Mill Process

One of the modern methods of production of round bars is the process of rolling in three-high skew rolling mill. This method enables the production of bars with both standard materials as well as hard deformation materials. In this paper, the results of theoretical and laboratory research of the 20 mm aluminum A1050 round rods rolling in three-high skew rolling mill process are presented. The numerical analysis was carried out upon applying the Forge 2011® software package. Based on the theoretical research, the stress, strain and temperature distribution during the rolling process were determined. In order to verify the numerical results, rolling aluminum rods were explored in laboratory conditions.

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