The Experts below are selected from a list of 3774 Experts worldwide ranked by ideXlab platform
Daisuke Nakamura - One of the best experts on this subject based on the ideXlab platform.
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Effects of Forming Conditions of Roll Offset Method on Sectional Shape at the Corner of Square Steel Pipe
MATERIALS TRANSACTIONS, 2013Co-Authors: Takuo Nagamachi, Takefumi Nakako, Daisuke NakamuraAbstract:Square steel pipes are reshaped from welded round pipes by Roll-forming. Effects of the Roll Diameter on the cross-sectional size of the square steel pipe were investigated by experimentation and three-dimensional finite element simulation. When the top Roll Diameter is greater than that of the side Roll, then the width of a corner part of the formed pipe is greater than the height. The square steel pipe was formed by offsetting the small Roll to the upstream side to make the width and height of a corner part equal. The offsetting result is affected by the longitudinal contact distance between a Roll and a pipe. The geometric contact length and relative offset, the offsetting distance/geometric contact length, were defined. The optimum value of the relative offset was clarified, which increased with the expansion of the contact length of a top Roll, the Roll gap and the round pipe wall thickness. [doi:10.2320/matertrans.P-M2013815]
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effects of Roll Diameter and offset on sectional shape of square steel pipe processed by Roll forming
Materials Transactions, 2011Co-Authors: Takuo Nagamachi, Takefumi Nakako, Daisuke NakamuraAbstract:A square steel pipe is reshaped from a welded round pipe by Roll forming. We investigated the effect of the Roll Diameter on the cross-sectional size of the square steel pipe by experimentation and three-dimensional finite element (FE) simulation. When the Diameters of the top and bottom Roll pairs are larger than those of the pair of side Rolls, the cross section width of the formed pipe is less than the height. To equilibrate them, we perform finish forming at the final stage. Furthermore, the width of corner part of the formed pipe is greater than its height. The difference between these two sizes of width and height of the corner part in the final product is greater than those at upstream stands and increases with the ratio of the Diameter of top and bottom Roll pairs to that of side Roll pairs. Offset the smaller Roll pairs upstream makes the pipe square. Such offset is effective for producing pipes with equal width and height at the corner.
Youngseog Lee - One of the best experts on this subject based on the ideXlab platform.
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a numerical approach to determine flow stress strain curve of strip and friction coefficient in actual cold Rolling mill
Journal of Materials Processing Technology, 2008Co-Authors: S M Byon, S I Kim, Youngseog LeeAbstract:Abstract An inverse scheme-based approach for the prediction of flow stress–strain curve and friction coefficient using actual mill data is presented. The equations for Roll force and forward slip are selected as the basic ones. Then they are inverted such that the deformation resistance and friction coefficient can be expressed as a function of process parameters measurable during Rolling such as strip width, entrance and delivery thickness, forward and backward tensile stress, forward slip, Roll force and Roll Diameter. A procedure for solving the inverse equations is described in detail. It includes steps which solve non-linear equation and generate the flow stress–strain curve from the data set of deformation resistances using the least square method. The capability of the present approach is verified by applying it to a reversible cold Rolling mill. A good agreement is noted between the predicted flow stress–strain curve and the measured one.
Takuo Nagamachi - One of the best experts on this subject based on the ideXlab platform.
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Effects of Forming Conditions of Roll Offset Method on Sectional Shape at the Corner of Square Steel Pipe
MATERIALS TRANSACTIONS, 2013Co-Authors: Takuo Nagamachi, Takefumi Nakako, Daisuke NakamuraAbstract:Square steel pipes are reshaped from welded round pipes by Roll-forming. Effects of the Roll Diameter on the cross-sectional size of the square steel pipe were investigated by experimentation and three-dimensional finite element simulation. When the top Roll Diameter is greater than that of the side Roll, then the width of a corner part of the formed pipe is greater than the height. The square steel pipe was formed by offsetting the small Roll to the upstream side to make the width and height of a corner part equal. The offsetting result is affected by the longitudinal contact distance between a Roll and a pipe. The geometric contact length and relative offset, the offsetting distance/geometric contact length, were defined. The optimum value of the relative offset was clarified, which increased with the expansion of the contact length of a top Roll, the Roll gap and the round pipe wall thickness. [doi:10.2320/matertrans.P-M2013815]
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effects of Roll Diameter and offset on sectional shape of square steel pipe processed by Roll forming
Materials Transactions, 2011Co-Authors: Takuo Nagamachi, Takefumi Nakako, Daisuke NakamuraAbstract:A square steel pipe is reshaped from a welded round pipe by Roll forming. We investigated the effect of the Roll Diameter on the cross-sectional size of the square steel pipe by experimentation and three-dimensional finite element (FE) simulation. When the Diameters of the top and bottom Roll pairs are larger than those of the pair of side Rolls, the cross section width of the formed pipe is less than the height. To equilibrate them, we perform finish forming at the final stage. Furthermore, the width of corner part of the formed pipe is greater than its height. The difference between these two sizes of width and height of the corner part in the final product is greater than those at upstream stands and increases with the ratio of the Diameter of top and bottom Roll pairs to that of side Roll pairs. Offset the smaller Roll pairs upstream makes the pipe square. Such offset is effective for producing pipes with equal width and height at the corner.
Xu Jian - One of the best experts on this subject based on the ideXlab platform.
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Effect of Work Roll Bending Force on Hot Rolled Strip Profile
Journal of Iron and Steel Research, 2003Co-Authors: Xu Jian, Smc LongAbstract:In order to build the high accuracy calculation mathematic model of hot Rolled strip profile, the Influence Efficiency Calculation Software was developed by Gmethod for researching the regularity of effect of Roll bending force on hot Rolled strip profile. The numbers, the ground influence ratio of work Roll bending force in 4high mill were calculated and the hexad multinomial fitting coefficients of work Roll bending force influence ratio revised indexes by work Roll Diameter, division draught pressure and reduction were found. The high accuracy calculation model of work Roll bending force influence ratio was constructed. A theoretical basis was afforded for contRolling strip profile.
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Effect of Unit Width Rolling Force on Hot Rolling Strip Profile
Journal of Northeastern University, 2003Co-Authors: Xu JianAbstract:In order to build the high accuracy mathematic model of hot Roll strip profile,the influence ratio calculation software is developed with influence coefficients method,based on the theory of strip profile′s calculation. The ground value of special Rolling force influencing ratio were calculated. The hexad polynomial fitting coefficients of special Rolling force influencing ratio revised coefficients(revised by work Roll Diameter and back up Roll Diameter) were computed. The universal calculation model of special Rolling force influencing ratio was built. The influence of special Rolling force and Roll Diameters on hot Roll Diameters on hot Roll strip profile were analyzed systematically. It is shown that along with the increasing of strip width,the changing curves of special Rolling force influence ratio in 4 high mill change as parabola,the effect of work Roll Diameter and back up Roll Diameter on special Rolling force influencing ratio play an important role. The simulation can be supplied for the strip profile control and the optimization of model coefficients.
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Effect of Roll Diameter on Hot Roll Strip Profile by Analytic Modelling
Journal of Northeastern University, 2002Co-Authors: Xu JianAbstract:?A calculation software was developed by Gmethod to examine the effect regularity of Roll Diameter on hot Roll strip profile. The quintic multinomial fitting coefficients of work Roll Diameter and backup Roll Diameter's influence ratios( ground value) in 4high mill were calculated separately, the revised indexes of the Diameter of work Roll and backup Roll to Roll Diameter's influence ratio were found. The high accuracy calculation module of Roll Diameter's influence ratio was built. The present work offers theoretical basis for the optimization of strip profile control module's coefficients.
S M Byon - One of the best experts on this subject based on the ideXlab platform.
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a numerical approach to determine flow stress strain curve of strip and friction coefficient in actual cold Rolling mill
Journal of Materials Processing Technology, 2008Co-Authors: S M Byon, S I Kim, Youngseog LeeAbstract:Abstract An inverse scheme-based approach for the prediction of flow stress–strain curve and friction coefficient using actual mill data is presented. The equations for Roll force and forward slip are selected as the basic ones. Then they are inverted such that the deformation resistance and friction coefficient can be expressed as a function of process parameters measurable during Rolling such as strip width, entrance and delivery thickness, forward and backward tensile stress, forward slip, Roll force and Roll Diameter. A procedure for solving the inverse equations is described in detail. It includes steps which solve non-linear equation and generate the flow stress–strain curve from the data set of deformation resistances using the least square method. The capability of the present approach is verified by applying it to a reversible cold Rolling mill. A good agreement is noted between the predicted flow stress–strain curve and the measured one.
