Prsentation PowerPoint

Industrialization of Cross Wedge RollingEric FREMEAUX1, Catalina GUTIERREZ2, Laurent LANGLOIS2, Philippe MANGIN2, Rgis BIGOT2, Pierre KRUMPIPE3, Valery SHCHUKIN4

With the technical and scientific support of: IWU Chemnitz, Dr-Ing Hab. Bernd LORENZ

1Ateliers des Janves, Avenue des marguerittes, 08120 Bogny-sur-Meuse, France2ENSAM, 4 rue Augustin Fresnel, 57070 Metz, France3CETIM, 7 rue de la Presse, 50802 Saint-Etienne cedex 1, France4Physical Technical Institute, 10 Kuprevich Street, 220141 Linsk, Belarus

NNSummaryIntroductionCWR principleAdvantages and disadvantagesObjectives

CWR tool designDesign rulesApplication

To increase CWR Tool LifeIdentification of the limiting phenomenonExperimental numerical investigation

Conclusion and future evolution

NNIntroductionThe two main configurations industrially developed are: (A) flat type and (B) two roll type [Li, et al., 2008].

Flat wedge type

Two-roll typeCWR is a metal forming process in which a cylindrical billet is plastically deformed into another axisymmetrical shape by the action of wedge segments.

CWR Facilitiesat Ateliers Des Janves

NNCross wedge rolling

Double-diameter reduction.CWR tool with 2 wedges.Rolled parts can be of simple diameter reduction or of several reductions. Five-diameter reductionsCWR tool with 5 wedges

Simple diameter reduction.CWR tool with 1 wedge. [PATER 2010]

NNAdvantages and disadvantagesBenefits [Li and Lovell 2002] [Li and Lovell 2008]Material and energy saving process with lower environmental impact.Higher productivity (cycle time up to 5 10 sec).High accuracy and maximum proximity to required dimensions of finished products.Difficulties [Weronski and Pater 1992]:Process with a high degree of technological complexityNumber of parameters affecting the stability of the process. Relationship between the parameters that must be correctly chosen in order to avoid failures.Slight variations in basic parameters can have a high impact on the rolled part. CWR tool design has been based on the experience and intuition of designers. No decision-making tools publicly available to the date.Tool manufacturing and development cost

Cross Wedge RollingForging RollingNNce qui rend le procd intressant du point de vue environnemental.Gain notoire en termes de mise au mille

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Introduction

Application

Preform: Hot forging of connecting rodRobotized forging workcellHammer

Productivity150% higher / Classical lineQuality: number of scrap parts / 2Material saving (5%-15%)NNObjectivesIn order to increase the performances of CWR

To reduce the developing time and cost of new CWR tool

To reduce the experimental part of the tool developmentTo automate as far as possible the tool design methodology

To improve the life of the CWR tools

To increase the life of CWR (Number of parts manufactured per tool)To stabilize the tool behavior To reduce the dispersion of the tool lifeTo reduce the number of defect types limiting the tool life NNSummaryIntroductionCWR principleAdvantages and disadvantagesObjectives

CWR tool designDesign rulesApplication

To increase CWR Tool LifeIdentification of the limiting phenomenonExperimental numerical investigation

Conclusion and future evolution

NN

Diagram of a wedge configuration [PATER 2003] CWR Tool Design

CpCgCeCc 02 01 02 03YpLexxyyzzProfil 01Profil 02Profil 03 03 01Geometrical parameters of die configurationParameters of die configuration- Identification of the tool design parameter

It is based on the parametric definition of the desired rolled part and on the parametric definition of the tool.

NNCross wedge rolling tool design procedure COLT

Design rulesIntegrate the state of art and expertise as far as possible

Design rules found in literature and identified during experimental work.Design rules are associated with stability indexFlexible tool by allowing updating of the already existing rules and the implementation of new design rules;

[Fu and Dean 1992] Risk of central porosity [Fu and Dean 1992] NeckingStability Index:

Associated with design parameters or function of design parameters

Associated with each defectNNWhen inputting the geometric characteristics of the desired rolled part we obtain the geometic characteristics of the tool 10Cross wedge rolling tool design procedure COLT

Output:Geometrical parameters of the CWR toolCoordinates of remarkable points for flat type and/or two-roll typeStability Indexes (potential defects)

.txt file with coordinates of remarkable pointsNNCross wedge rolling tool design procedure COLT A decision supporting methodology for the designing of the tool in CWR is being developed.Solution provided by COLT is not expected to be immediately efficient but as close as possible to a performant solution. Synthesis of literature and experimental rules.The designing rules allow the selection of basic parameters.An stability index is introduced to take into account the inconsistencies in literature.The advantages of the methodology are:Non-expert user will have a first guided approach to the CWR process.Identification of the potential defects with the associated basic parameters.Flexibility of the methodology by the updating of exiting rules and implementation of new ones.ConclusionsBenefitsNNA decision supporting methodology for the designing of the tool in CWR is being developed.It is based on a synthesis of literature and experimental rules.The designing rules allow the selection of basic parameters.An stability index is introduced to take into account the inconsistencies in literature

The advantages of the methodology are:Reliability on scientific and experimental bases.Relationship between the parameters at all time during the COLT procedure. This allows to observe the interaction and effects of the designing decisionsFlexibility of the methodology. An user can obtain different wedges by modifying one parameter.

Interactive method. The bibliographical and experimental references as well as it maturity can be modified, eliminated or even adding new sources.

12SummaryIntroductionCWR principleAdvantages and disadvantagesObjectives

CWR tool designDesign rulesApplication

To increase CWR Tool LifeIdentification of the limiting phenomenonExperimental numerical investigation

Conclusion and future evolution

NNTool Life in CWR are limited by geometrical defects of the rolled partThe forged part doesnt meet its requirementsDefects Dimension

The shape of the rolled part cannot be hot forged

Common defects on CWR products [Li and Lovell 2002]CWR Tool Life

Spiral groove and striationCenter cracking

NMethodologyIdentification of the statistical correlations between:Geometrical, kinematical, thermo mechanical parametersandLimiting phenomenon

Initial value and evolution of the parameters along the tool lifeRelative initial position of the different parts constituting the toolsDifferential Kinematics of the toolsEvolution of the shape of the tool due to wearDistribution of the temperature at the surface of the toolCWR Tool LifeNSynchronism of two-roll tool during rollingHigh speed cameraSchema installation

recorded image by the high speed camera

Synchronism of the grooves passing through a fixed frame was studied.An analysis of the average angular velocity was calculated by measuring the time between two grooves through the fixed frame.CWR Tool LifeN

Evolution of tool wear Non-contact 3D measurement methods

Computer stereo vision

Relative position of the different parts of the toolEvolution of the geometry due to wearCWR Tool LifeNConclusions and perspectives

1- Experimental and statistical identification of the correlation between tool and process parameters and the phenomenon limiting tool life

2- Experimental and modelling-simulation investigation

Statistical relation Qualitative Quantitative Physical relation

3- To design and to implement solutions in order to increase and better control the life cycle of the CWR tool.

4- Integration of the result as knowledge withn the tool design methodologyNew design rulesNew process parameters

CWR Tool LifeNIndustrial Academic PartnershipENSAM CETIMState of the artIdentification of the key parametersInitial version of the design methodology (Formalization of the know-how)

Scientific et technological support of PTI and IWUFinancial support of Region LorraineAteliers des JanvesInvestmentIndustrial implementation of the CWRKnow-how and experience

Skill- Knowledge management- Process thermo mechanical simulation- Measurement and control of manufacturingprocessIndustrial requirementKnow-howIndustrial facilitiesFruitfull collaborationIncrease of the skill based on scientific and technological approachIntegration of the skill as computer aid tool for the industrialization of the process

NThank you for your attention

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