Extrusion Technology

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Magazine 2017/3

ENERGY AND DATA MANAGEMENT IN MEDIUM-LARGE EXTRUSION PRESSES
Davide Turla, Luca Fogliata - Turla s.r.l.- Italy

Abstract. Medium and large extrusion presses and extrusion systems find a large application in the production of automotive and industrial products but at the same time are also used for different applications ranging from building systems up to heavy and wide profiles for railway application.

These different type of extrusions involve certainly many different aspects and sometimes they must be really approached as different industries but two factors remain always unvaried, whatever the final products are:

1)      Low energy consumption at high production rate
2)      Automatic data acquisition     

For this reason, Turla is normally equipping all its 35-40MN extrusion presses and extrusion systems with:

1)      Eco+Logic 2.0: Turla special hydraulic set-up system for low energy consumption and low noise emission
2)      ADAM - Advanced Data Acquisition Management:  Turla acquisition data system. 

(Read Full Article)

 

Continuous Improvement And OEE Application In An Aluminium Extrusion Factory
M. Bertoletti, G. Mainetti, T. Mainetti - A.t.i.e. Uno Informatica S.r.l., Italy

Abstract: Productivity and quality increase is an essential target of any production process, including the extrusion one; the paper describes the application of Kaizen method for continuous improvement supported by OEE analysis on an extrusion floor, and the results achievable with its application.
Kaizen method and OEE analysis were applied typically on advanced sectors and production processes, with products requiring long times-to-market, in terms of months or even years.
The application of such concepts on a process-based industry like the aluminium extrusion, with small production lead times, even lower than thirty minutes, is a challenge that now can be faced thanks to the development and the application of dedicated systems.
Such kind of analysis is not widespread as it requires an identification of multiple production parameters and their automatic collection, available on modern plants only (or revamped ones): due to this factors the KPI utilized the most until now is the Productivity (KGs/hour), which represents one metric only of the OEE indicator (OEE = Availability x Performances x Quality).

(Read Full Article)

 

Magazine 2017/2

USE AND FABRICATION OF ALUMINIUM EXTRUSION PROFILES FOR THE SOLAR INDUSTRY

Giovanni Barbareschi, Fom Industrie S.r.l., Italy

Abstract

The paper initially presents various solutions that are available for the fabrication of aluminum extrusions for the PV panels frames, racking systems and Parabolic Trough CSP spaceframes. The option between Automation and manpower together with the level of flexibility in the product manufacturing processes determine the capital investment required for the deployment of the fabrication equipment as well as the achievable production capacity: all these factors must be properly balanced in order to be able to produce parts whose cost can be accepted by the solar market. In spite of the manufacturing solution being used, when dealing with aluminum extrusions used in an environment subject to large thermal excursion, the effect of Thermal expansion must be carefully considered. Based on a detailed analysis of the Thermal Expansion static and dynamic phenomena on aluminum extrusion framing, some useful guidelines are outlined for the design and manufacturing of aluminum spaceframes for the Solar Industry.

(Read Full Article)

 

CHARACTERIZATION AND MODELING OF FRICTION BEHAVIOR FOR SIMULATION OF EXTRUSION PROCESSES

Dong-Zhi Sun, Andrea Ockewitz and Florence Andrieux, Fraunhofer Institute for Mechanics of Materials IWM, Germany

Abstract

Extrusion processes are essentially influenced by friction between billet and extrusion tools. Not only process parameters but also the microstructure and mechanical properties of extrudates depend strongly on friction effects. A reliable determination of friction behavior is important for the construction of extrusion tools and optimization of whole extrusion processes. The problems for characterization of friction effects in extrusion processes are that common friction tests like pin-on-disk don’t give relevant information about friction in extrusion situations due to lower hydrostatic stresses. There are few results about influence of normal stress, temperature and velocity on friction. In this work, a two-step friction test was developed which allows a systematic change of normal stress, temperature and velocity. FE simulations were performed to analyze the loading situations and a modified shear friction model was derived based on the experimental results. A limitation of this friction test is that the plastic deformation of the cylindrical specimen is very small. To enable large plastic deformation of the specimen during a friction test an alternative test setup is suggested. The geometries of the die and specimen have to be further optimized taking into account both relevance to real extrusion processes and predictability of the friction behavior by numerical modeling. The friction tests were simulated with the FE code HyperXtrude. (Read Full Article)

 

Magazine 2017/1

HybrEx – Innovative Extrusion Press with Hybrid Drive Technology

A. Bauer 1, U. Muschalik, Dr. J. Magenheimer 1 SMS Meer GmbH, Germany

Abstract

Radical new approaches reduce the hydraulic drive of extrusion presses, minimize power consumption, increase productivity and implicate an unmatched dynamic to the extrusion process. Since profiles and tubes have been produced from light and heavy metals by extrusion, new and further developments from SMS Meer, including all press types grouped today under the brand name "Schloemann Extrusion Presses", had a significant influence on extrusion technology and set always new milestones. While developments in earlier years were focussing on optimisation of the extrusion technology, the recent development steps aimed to increase energy efficiency and productivity. Anyone who thinks that only marginal improvements are possible in this area can now be impressed by a new development from SMS Meer. Thanks to radical new approaches, that were resulting in a hybrid drive concept, the new HybrEx extrusion press sets a new benchmark in terms of energy efficiency. (Read Full Article)

 

Tailor made die cleaning systems and affordable/ecological caustic soda recovery equipment with fast payback

Marcello Rossi, Italtecno Srl, Modena - Italy

Abstract

The latest studies about die cleaning and caustic soda recovery after die cleaning in the extrusion industry have brought to the development of different models of equipment not only based on the number of dies to clean but also on the different investment budgets of the extrusion industries. The results are small, medium and large size equipment with manual semi-automatic or fully automatic functioning, but also low cost equipment: for example recovery of caustic soda from die cleaning can be obtained using centrifuges (high efficiency and small amount of solid waste) or more economic filtration systems like filter-presses where the lower efficiency is compensated by lower cost.(Read Full Article)

 

 Magazine 2016/4 

6XXX-CRASH ALLOYS FROM HAI: AN EXAMPLE OF THE SUCCESS STORY OF THE COMPLETE VALUE CHAIN UNDER ONE ROOF

Kühlein Wolfgang, Schiffl Andreas - Hammerer Aluminium Industries Extrusion GmbH, Austria

Abstract

Considering achieving the crash-requirements of OEMs Hammerer Aluminium Industries Extrusion (HAI) has started a research and development program several years ago. The major topic has been to understand what happens inside
the material during all steps of the process route.
HAI knows now which parameters are influencing the crash performance of high strength 6xxx alloys.
The complete process route under one roof plays an essential rule for HAI.
Therefore it allows us to adjust the microstructure by influencing the parameters starting from the melting of recycled scrap to extrusion, heat treatment and finalization. In detail the five major points are the chemical composition, the type of extrusion die, temperatures of the billet, container and profile outlet, the cooling parameters and at the end
the artificial heat treatment.
The paper will point out some of the above mentioned important production steps in terms of understanding the parameters influencing the successful production of high strength 6xxx-crash alloys. (Read Full Article)

 

FEASIBILITY OF A NEW EXTRUDED PROFILE: COMPUTING OF THE OPTIMAL EXTRUSION PARAMETERS IN THE EARLIER STAGE TO REDUCE THE PRE-PRODUCTION CYCLE

M. Bertoletti1, E. Mainetti1, G. Mainetti2, C. Seclì3 
1A.t.i.e. Uno Informatica S.r.l., Italy
2Politecnico di Milano, Mechanical Department, Italy
3Altair Engineering srl, Italy

Abstract

During the last years the main goal of research on aluminium extrusion process has been the reduction of the product time to market. The first stage of pre-production feasibility evaluation of a new profile at the state of the art requires a long time and sometimes it can engage different human resources for many days.
The innovative method we are introducing allows the extruder to search automatically, in a large database of sections images, profiles already extruded that are similar or identical to the new one. This research can be performed with different accuracy on the entire profile or just some detail of it. The new profile can be researched starting from the CAD drawing, a hand-made sketch, an image sent by email or fax or even scanning a real profile utilizing specific scanners. The research time depends on the size of the database and the type of research that is performed, but it is
much faster than a “human made” one, that is currently performed. This system lets the operator extract some important parameters of the similar profiles found that can be utilized in another module of the system to estimate the theoretical production parameters using an analytical calculation method: this method requires Altair’s HX-PROCESS libraries.

HX-PROCESS is a computer aided engineering tool specially designed to help aluminium extrusion plants to determine the optimum processing conditions, billet length, extrusion speed, billet preheating, taper, etc. to estimate the productivity on different presses and to perform costs analysis.
Finally, using the technologies we are presenting in this paper an extruder can reduce the pre-production time from different days to some hours or even some minutes. This considerable time saving brings important advantages in term of human resources availability and money. (Read Full Article)

 

“QUALITY THROUGH DESIGN – SECO/WARWICK CONTINUOUS LOG HOMOGENIZING PLANT CONCEPT PROVIDING UNSURPASSED FLEXIBILITY”


Krzysztof Niemiec - SECO/WARWICK S.A., Poland

Abstract

In the area of extrusion log & billet homogenization of Aluminium 6xxx series alloys (commonly called “soft alloys”), plant managers face high quality requirements, out of which the following two are the most important:
• to provide uniform structure and suffi cient extrudability of the billets within entire cast, allowing to obtain high extrusion speeds and appropriate mechanical properties of extruded profiles 
• to obtain good side surface of the logs without any scratches, damages, oil stains, spots and other imperfections to maximize metal recovery (yield). 

In many cases, cast house managers are obliged to meet these requirements for a wide variety of log diameters, typically from 6-7” to 14-16”. In the same time, they are forced to reduce operating costs, which are mainly related to energy consumption and workforce. All these facts cause it is challenging to meet and maintain high quality standards to low operating costs for a broad range of log diameters. 

SECO/WARWICK, basing on IUT vertical continuous homogenizing technology, has developed an original concept of continuous homogenizing plant to provide more versatile and fl exible equipment than any other existing solution on the market. The paper presents the idea of the innovative continuous homogenizing furnace design and the benefi ts it brings to users. (Read Full Article) 

 

Magazine 2016/3

 

AUTOMATED EXTRUSION DIE DESIGN INTEGRATED WITH SIMULATION OF MATERIAL FLOW

Nikolay Biba - Micas Simulation Ltd., UK
Sergey Stebunov, Andrey Lishny, Alexey Duzhev - QuantorForm Ltd., Russia

Abstract

After years of intensive development, the numerical modelling of extrusion has reached a certain maturity and practical applicability. An essential requirement for effective extrusion simulation is the availability of reasonably good quality 3D CAD models of dies. However many die makers still produce their products using 2D drawings and do not have full 3D models of them. To bridge the gap between requirements of simulation and limitations of industrial practice, a new automated system of 3D die design has been developed. This system not only speeds up the creation of 3D models of the dies but also has an interface to the simulation software QForm-Extrusion that provides rapid analyses of the material flow in newly developed dies and allows improving the design by virtual corrections before actual manufacturing. The paper presents basic principles of this approach and an industrial case study that illustrates all stages of such combined die design and simulation procedure. (Read Full Article)

 

CONCEPTUAL TESTING OF PRESS FORM HARDENING OF HIGH-STRENGTH ALUMINIUM ALLOYS

Ola Jensrud, Knut Erik Snilsberg, Arne Kolbu
Department of Materials Technology, SINTEF Raufoss Manufacturing, Norway

Abstract

The uses of age-hardenable and high-strength aluminium sheet materials in automotive applications may be superior to those using low-strength alloys, especially if the processing of the components is cost-effective. This study demonstrates that the hot forming of sheets has benefits when compared with cold forming in terms of spring-back, formability and microstructural control. The sheet materials tested (AA6082 and AA6070) both represent options when a combination of strength and ductility is an issue. A thermo-mechanical process (TMP) is used involving a press-quench tooling set-up. The solution heat treatment sequence integrates the hot forming of the blank material with direct ageing resulting from the press operation. Using a generic component, it is possible to demonstrate high formability of the alloys with short artificial ageing time in order to achieve the required strength. This new approach appears to succeed in achieving accurate geometrical tolerances, uniform properties and high productivity for aluminium automotive components. (Read Full Article)

 

Magazine 2016/2

HIGH EFFICIENCY APPROACH TO EXTRUSION CORE  

ALESSANDRO GUERRINI
Turla S.r.l. - ITALY

Abstract

Modern extrusion systems must meet, more and more, absolutely precise and stringent performance requirements and at the same time must allow end users to reach these performances with the greatest efficiency.

The most critical steps in the aluminum extrusion are the following:

1) Log  heating

2) Billet pressing

3) Profile quenching 

These steps are at the same time:

1) The most critical for the correct achievements of metallurgical and geometrical properties of the end product

2) The most energy expensive in the complete extrusion project   

The ability to perform these steps with the lowest energy consumption determines most of the time the success of one company versus its competitors. In particular the following aspects have been analyzed and solved to offer machines tackling adequately these challenges, listed below the features of the machines that help in this regard... (Read article)

 

ALUMINIUM APPLICATION IN MODERN LIGHT-WEIGHT CAR DESIGN 

Jürgen Hirsch
Hydro Aluminium Rolled Products GmbH - Germany

Abstract

Aluminium is the most suitable and fastest growing lightweight material for automotive applications, as castings, extrusions and sheet. Aluminium is in fi erce competition with well established and advanced steel solutions, Magnesium and Carbon/Glas Fibre Reinforced Plastics.
Here the results of Aluminium car design evaluated in the “SLC” (“SuperLIGHT-CAR”) project on “Sustainable production for Emission Reduced Lightweight Car Concepts“ are presented, where new solutions for signifi cant weight
reduction in cost-effective mass produced “Golf-class” cars have been evaluated in a Multi-Material-Design. The final prototype BiW included 64% aluminium parts as sheet, extrusions or castings and reached 35% weight reduction with additional part costs of 7,8 €/kg saved. The developed Aluminium solutions are shown and the specific material spects are discussed. (Read article)

 

INNOVATION AFTER DIE CLEANING CAUSTIC SODA RECOVERY FROM EXTRUSION DIES: CASE HISTORY

Walter Dalla Barba, Marcello Rossi, 

Italtecno, Italy

ABSTRACT

In aluminium extrusion industry, the cleaning of extrusion dies is conventionally afforded by use large quantities of caustic soda cleaning solution, which needs to be regularly disposed by external companies.

The more and more stringent environmental Laws and the increasing ecological costs, have brought to the natural conclusion that the caustic solution should be recycled instead of being wasted.

It is described the case of an European extruder, where a new technology for automatic die cleaning and automatic recycling of caustic soda has been implemented on a full industrial scale and very successfully.

The reasons which led to this choice are listed. Also, the results of implementing this technology will be detailed, along with the change on operations, the beneficial cost effects, the dramatically reduced impact on a complicated urban environment. (Read article)

 

Magazine 2016/1

RECENT ADVANCEMENTS IN ‘STATE OF THE ART’ ALUMINUM EXTRUSION SIMULATIONS

Mike Foster, Deepu Joseph - Scientific Forming Technologies Corp., USA
Tushar Bakhtiani - VIP Tooling, USA

Introduction

Process modeling software based on the finite element method (FEM) is a valuable tool in analyzing metal forming processes [1,2]. Extrusion is one such process where important information can be gained by using simulation [3,4]. The material flow during extrusion can be analyzed, giving insight into the initial transient behavior in the die, weld seam formation, etc. Stresses in the die components can also be obtained using simulation, allowing die modifications to be analyzed to see if they would improve the stress state and make die cracking less likely.
Several techniques can be used to simulate the stresses in the extrusion dies. One option is to model the extrusion process using rigid dies that do not deform. A subsequent stress analysis can then be run at a particular step of the extrusion simulation, after switching the tooling components from rigid to elastic. This provides the stresses in the tools at that one particular instance in time. This is called a decoupled stress analysis.
This paper deals with a second technique called coupled die stress analysis. Some extrusion dies are designed to elastically deflect during the extrusion process. This deflection closes gaps between the tooling components that were initially present. In order to model the extrusion process in these dies, a coupled analysis is needed so that the die deflection can be accurately captured during the forming. This type of simulation needs to use the Updated Lagrangian (UL) finite element formulation so that the transient flow and die deflection can be captured. All UL simulations performed in this study used the process modeling software DEFORM-3D. These coupled extrusion simulations are very computationally intense and are considered to be ‘state of the art’.
Also discussed in this paper is a novel method for viewing material flow in Arbitrary Lagrangian Eulerian (ALE) extrusion simulations. ALE extrusion analyses, as implemented in DEFORM, use a mesh that does not update in the extrusion direction. Functionality has been developed to track the metal flow in these ALE simulations in a transient manner. This allows the location of weld seams to be predicted in either Updated Lagrangian or ALE simulations. (Read Article)

 

The Prime Source for Improving Extrusion Productivity

Paul Robbins, Lin Chun (Ken) Chien, Bill Dixon - Castool Tooling Systems, Canada

Abstract:

The ever-increasing pressure for higher productivity for the extrusion press, demands for better tooling and an understanding of the tooling systems. Most extruders know more contact efficiency, higher net recovery and faster ram speed improve extrusion productivity. Studies however show some extruders are able to produce net productivity rates as high as 2400kg/hr for a typical 8 inch billet, and some extruders only have net productivity rate at 2000kg/hr. The productivity discrepancy clearly shows, only few extruders truly understand the functions of their tooling. Many fail to achieve high productivity. Perhaps, some extruders place too little emphasis on the prime source of improving productivity. The paper will address the prime source for improving productivity. (Read Article)

 

Magazine 2015/4

 

 

A CONSOLIDATION OF OPTIMIZATION TECHNIQUES FOR ALUMINUM EXTRUSION OPERATIONS

Craig R. Werner, VP Extrusion Technology Kaiser Aluminum, USA
David Turnipseed, Belco Industries, Inc., USA

 

This paper combines and builds on seven prior ET (Extrusion Technology) Seminar papers (two of them Management Issues “Best of Track”) presented by the author at ET ’08 and ET ’12 and accompanying Light Metal Age articles. 

 

The aluminum extrusion process lends itself to mathematical optimization in a unique way.  When called on to teach neophytes about the process or how to optimize, “We Neither Create Nor Destroy Matter” is a key mantra. This paper will cover optimization techniques directly applicable to extrusion operations, which can be implemented by extruders in single parts, or in combination.  Topics will include: 

 

  • Continuous Extrusion Optimization System
  • A Two-Decade Case Study – How Modeling Drove Exceptional Results
  • Why Data Integrity is critical, and how to achieve it
  • Is Operational modeling Worth the Effort?
  • Optimization of Log Lengths and cut Mill Lengths
  • Using Linear Programming modeling techniques in an extrusion operation
  • Employee Motivation in an aluminum extrusion operation
  • WES LLC work on Benchmarking Aluminum Extrusion Operations
  • WES LLC Extrusion Optimizer

 

The author has more than three decades of experience developing and applying these techniques at his own company and other extrusion facilities. (Read Article)

 

NEXT GENERATION EXTRUSION PRESS CONTROL THERMOMETRY 

Jon Raffe Willmott, Susan Fiona Turner, Tom Rockett, Stuart Francis Metcalfe and Peter Drögmöller

Land Instruments International Ltd. 

We report on the next generation of radiation thermometry for extrusion press control and describe the latest algorithms we have developed for increased accuracy in measuring the temperature of aluminium alloy. Measuring and controlling press temperature is important for maintaining and improving process efficiency and die life. Aluminium temperature measurement is one of the biggest challenges in radiation thermometry due to the material’s low efficiency factor in emitting infrared radiation (known as emissivity) and the variable nature of this property both within and between different alloy types. We have recently developed four new non-contact radiation thermometers, for use in monitoring the extrusion process. The die exit thermometer and post quench thermometer both contain new algorithms that can adapt to changing emissivity and provide an accurate measurement on extruded aluminium.

(Read Article)

 

Magazine 2015/3

 

LONG TERM WEAR INVESTIGATION ON CVD COATED EXTRUSION DIES

Joachim Maier1, Rolf Beckert2 and Thuy-Vu Tran3
1 Joachim Maier, WEFA Inotec GmbH, Germany
2 Rolf Beckert, WEFA Inotec GmbH, Germany
3 Thuy-Vu Tran, WEFA Inotec GmbH, Germany

Abstract

Coated dies currently show different failure modes and lifetime. So far wear prediction was only possible under real extrusion condition. This is a time consuming method for developing and improving CVD coating systems for extrusion dies. Basic tribological testing in extrusion technology for a short time period was possible by means of tribo-cone-test-method [1]. Since long term wear phenomena were not possible to detect on coated dies so far a new methodology of accelerated lifetime testing (ALT) was implemented and a “close-to- extrusion”-condition wear tester. Different parameters like rotational speed, pressure and initial probe temperature have been tested with various CVD coatings against different Al- alloy and tool steel combinations. The aim is to find the optimum conditions to create a critical value for coating wear to be end of life criteria.

The High Temperature (HT)-CVD-coating has been established and well proven for standard extrusion applications. The newly developed Medium-Temperature (MT)-CVD-coating for extrusion dies show promising attributes in terms of e.g. profile surface quality [2]. Thus in the long-term tribological test stand the lifetime of MT-CVD [3] and HT-CVD probes were tested and compared with real die coating failures. For specific Al-alloy compositions (EN AW-3xxx, EN AW-6060, EN AW-6082) a wear versus time (or running meter) - chart was created to assess the specific wear pattern of each alloy both in the test probe as well as in the real die.

Besides abrasion phenomena the adhesion of various alloys inside the coated dies has an important impact mainly on profile surface quality. The adhesion effects were investigated in an adhesion test set-up and the relation between adhesion thickness and re-crystallization layers were discussed (Read More)

 

REINVENTING TOOLING MANAGEMENT TO OPTIMIZE EXTRUSIONS COST UNDER A STANDARD PRICE PER PIECE BASIS

Danilo G. Ciccola
ALREYVEN EXTRUSIONS, Maracay, Venezuela

Abstract

On the global aluminum extrusion market, competitiveness frequently drives extrusion companies to sell their profiles on a standard price per piece basis, thus, controlling costs and metal waste is important in order to keep them as lowest as possible. Among the vast production systems currently known in the world, cost modeling for extrusions could be very challenging for one reason: extrusions could generate an almost infinite quantity of designs, each of them with very specific production parameters.

Even though the world has experienced a huge progress on computer and electronics development, some manufacturing technique still relies on the expertise of experienced people on the business, so management procedures is an important tool to succeed. Even though extrusions are commonly sold considering weight ratio for any profile marketed, possibility arises when prices are set up on a standard per piece basis. The main purpose of this research is to analyze key elements such as metal (raw material) and die (tolling) influence to optimize production costs by implementing a standard procedure that enhances the best practices for tolling management. According to this case study; results shows that there’s a point in which the lowest extrusion cost takes place, therefore tools should be discarded (rejected).

Savings by using this method of analysis would depend on market conditions, prices, types of profiles and so on, savings could reach even 5% of original cost, giving a practical, simple and easy to implement method to keep competitiveness and increased revenues (Read More)

 

Magazine 2015/2

PERIPHERAL COARSE GRAIN FORMATION IN HIGH SILICON CONTAINING ALMGSI ALLOYS

Yusuf Demirci1, Zafer Zorlu1, S. Mutlu Ayan1, Kemal Çakır1, Özgül Keles2
1 Asas Aluminum Tic. A.S., Kucucek Mevkii Akyazı, 54440, Sakarya-TURKEY
2 Department of Metallurgical and Materials Engineering, Istanbul Technical University, Maslak, TURKEY

 

Abstract

AlMgSi aluminum alloys are preferred for structural applications in automotive, railway and aerospace industries. The quality of products, in terms of mechanical properties and surface quality, are very vital. Peripheral coarse grain growth (PCG) structure is one of surface imperfections that result in low machinability, mechanical properties and surface appearance. PCG is generally observed in high- strength aluminum alloys.

In this study, alloy composition, die design and extrusion process parameters have been investigated to understand the major factors effecting PCG structure in hard aluminum alloys and retarding PCG formation. The recrystallized layer thickness was examined using optical and electron microscopy, the hardness of the layer was measured. Significant improvement on PCG has been obtained by changing die design and alloy composition. (read more).

 

AN OPTIMIZED TRIBO-TESTING METHOD FOR COATING INVESTIGATIONS FOR ALUMINIUM EXTRUSION DIES

Christoph Becker1, Pavel Hora1, Joachim Maier2

1ETH Zürich, Institute of Virtual Manufacturing, Switzerland
2WEFA Singen GmbH, Germany

 

Abstract

During the extrusion process complex tribological effects between the die surface and the extruded material occur. The recently designed and optimized “Torsion-Tribo-Test” allows the investigation of these tribological phenomena under different load, velocity and thermal conditions. The main advantage of this new developed testing method is its Al-sample volume constraint and due to that a constant friction area also in use of high pressure.

The following investigations have not been carried out only with conventional nitrided samples but also with coated ones. Several CVD (Chemical Vapor Deposition) coatings have been applied to the tool-samples and tested against Al alloys. With this new experimental setup a first step is made to test conventional and new-developed coatings under extrusion conditions in a laboratory environment.

In the context of this study the optimized “Torsion-Tribo-Test” for evaluating tribological phenomena will be presented. Besides the experimental setup, the tribological results of measurements for different thermo-mechanical conditions will be presented and discussed too. (read more)

 

 

Magazine 2015/1

 

AN INNOVATIVE, FAST AND ACCURATE FEM METHOD FOR THE PREDICTION OF DEFORMATION AND STRESSES IN ALUMINIUM EXTRUSION DIES  

A.J. Koopman, ALKO Engineering, Netherlands

 

Abstract

 

Optimizing aluminium extrusion dies using the predicted occurring stresses and deformations whilst designing the die, decreases the chance of breakage, profile deformations and flow problems during extrusion. However design time is limited and the traditional simulations require much time to get the stress and deformation results. In this paper a faster FEM method is shown that predicts the stresses and deformations in the die. The basic assumption, that the forces of the aluminium on the die can be captured in analytical formulas, is proven to be accurate (read article).

 

 

Magazine 2014/4

QUANTITATIVE EVALUATION OF PORTHOLE DIES DESIGN PRACTICES BY MEANS OF FE ANALYSES

Tommaso Pinter - Alumat & Almax Mori, Italy

Barbara Reggiani - University of Bologna, Italy

Abstract

During the last decade, finite element simulations have became a very useful technology for tool designing, especially in such cases, like in the extrusion process, where on-plant die trials are expensive and sometimes of difficult interpretation.

However, even if good die-design practices are well known by the leading industry players, quantitative evaluations of commonly adopted die-design solutions are seldom available in literature.

This contribution presents the preliminary results of a new approach for porthole dies design optimization by means of finite element analysis using HyperXtrude® software (read article)

 

HYDRAULICS AND CONTROLS RETROFIT CAN BREATHE NEW LIFE INTO YOUR EXTRUSION PRESS

Jeff Grube
Bosch Rexroth Corporation (www.boschrexroth-us.com)

Introduction

Aluminum parts producers are carefully assessing the performance of their extrusion presses as customers such as vehicle component manufacturers, aerospace suppliers, window and door (fenestration) suppliers and other high-volume users seek faster turnarounds and smaller order lot sizes. Customers are also requiring more complex profiles and extrusions with lowered costs.

These industry conditions, along with consolidation among aluminum shapes suppliers, are creating greater operational demands on presses. When parts makers consolidate, they typically move work onto one press and maximize its use, which can strain the machine, particularly older presses.

Although some parts producers may feel compelled to completely replace an old extrusion press to keep up with production demands, this major investment may not be necessary. If the press frame is sound, a retrofit and upgrade of key press components, such as hydraulics and controls, can extend the life of the press and provide a more flexible, reliable, long-term manufacturing solution that meets the needs of the extruder and raises press performance levels. (read article)

 

Magazine 2014/3

NON-CONVENTIONAL DIE FOR A THERMAL BREAK PROFILE

Sutanay Parida, Gulf Extrusions Co., U.A.E. 

Abstract:

Thermal Break profile is a combination of two types of profile attached together by a heat resistant (Polyamide) strips. Both the profiles are generally extruded from different dies and could be from different Presses. In most of the cases the production of both the profiles at same time with equal numbers, always remain a challenge to the extruders. Similarly when these profiles are further process for Anodizing or Powdercoating, controlling of different baskets carrying different profiles not only make the whole process chain delayed but also create an unbalanced process load. But by studying every step and re-engineering the process flow, a die with two cavities having different profile developed which ultimately resulted in to an ON-TIME delivery and cost effective production of the thermal break profiles. (read more)

 

PREDICTION OF GRAIN SHAPE EVOLUTION DURING EXTRUSION AND ANNEALING OF 6XXX ALLOY

Antonio Segatori, Barbara Reggiani, Lorenzo Donati, Luca Tomesani

DIN-Department of Industrial Engineering, University of Bologna, Italy

Abstract

In the extrusion of aluminum alloys the process chain involves different steps of thermo-mechanical stresses of the material leading to deformation of the grains during plastic forming and several degrees of static recrystallization during cooling. In defective cases, peripheral grain coarsening may occur thus causing profile scrapping. The implementation of a predictive tool able to simulate the whole complex sequence of phenomena involved in the extrusion process, consequently results of considerable interest. Experimental and numerical analysis were performed to investigate the grain shape evolution of 6XXX aluminum alloy during the extrusion process in order to develop a prediction model. A first experimental campaign was carried out in order to investigate the texture deformation modes and retrieve the microstructure evolution model. This model was coupled with the analytical static recrystallization formulations available in literature for the final implementation in a commercial FE code. A unified model was therefore implemented through user-routine, thus carrying the innovation of a model able to simulate grain evolution during the entire process: deformation and following ageing with an integrated approach. A second experimental campaign was used to validate the model on a wide industrial range of Zener-Hollomon values, comparing the experimental and numerical results at the end of the dynamic evolution and of the consequent static recrystallization. The results were analysed also in terms of grain growth effect, although this phenomenon is still not well captured by the model. (read more)

 

Magazine 2014/2

EXTRUDER AUTOMATION SYSTEM WITH SELF-SETTING CAPABILITY

Madhukar Pandit, University of Kaiserslautern, Germany

Abstract

In an extruder for producing aluminium profiles, process parameters, such as the ram speed run and the desired profile temperature at the die exit have to be set before starting an extrusion cycle. Whereas for the second and succeeding cycles, the settings can be adjusted manually or automatically based on the variables measured in the previous cycle(s) and the quality of the resulting product, the task arises that the initial settings for the first cycle have to be chosen appropriately. In the paper, a new method for automatically setting the process parameters is described which is based on storing data of product features and corresponding optimal process parameters in a data base and employing techniques of artificial intelligence to estimate the initial settings. The implementation and performance of a system using a MS SQL Eexpress server in a real extruder are given. The facility can be extended to a comprehensive database system which caters to the requirements of marketing, production control, process automation and quality control. (Read article)


A COMPARISON BETWEEN DIFFERENT APPROACHES IN THE EVALUATION OF EXTRUSION DIE LIFE: STATIC STRENGHT, FATIGUE AND CREEP

Barbara Reggiani, Lorenzo Donati, Luca Tomesani
DIN- Department of Industrial Engineering, University of Bologna, Italy

Abstract
The demand of high quality extruded products involves the requirement of an increasing efficiency of the production systems leading to severe operational conditions for the die. Among different classifications proposed in literature for die failures, one focus on separating manufacturing and in service failures. The latter category is additionally split, as proposed by the authors, in static failure, damage and deformation/deflection failures. Static failure appears after e reduced number of extruded billets as a consequence of an overload or poor initial die design. Damage and deflection failures are indeed induced by the synergic detrimental action of creep and fatigue phenomenon. All the failure mechanisms are die design and in-service conditions dependent. In particular, in discriminating the dominant role of creep and fatigue in leading to final die discard, a considerable role is played by the dwell time. This is the time of constant load acting on the die and represents the time required to extruded each single billet function of both ram speed and billet length. Fatigue and creep can be seen as limit cases with zero and infinite dwell time. A novel model is proposed for the prediction of the deformation undergone by extrusion dies in the creep-fatigue regime after multiple cycles (i.e. multiple extruded billets) based on a modified version of a simple creep law already implemented in all the FE codes. The starting point is a physical experiment reproducing the thermo-mechanical conditions of a die. The model allows to account also for the dwell time. The model has been validated against small scale dies. A test was also performed on an industrial hollow die used in a controlled experiment. (Read article)


Magazine 2014/1

BENEFITS OF AUTOMATING YOUR DIE-POLISHING USING ADVANCED AFM TECHNOLOGY

John Stackhouse, Micro Technica Technologies, Germany

Abstract

Traditional Die polishing of the Bearings, using skilled technicians, can be replaced by a machine control-based technology that provides benefits of cost-savings and quality improvements.The newest form of Abrasive Flow Machining (AAFM) Technology, with pre-programmed control of Media flow-rate, counter-pressure, temperature and other machine settings is proving to be productive; with improved Die life, profile quality and extrusion throughput. New Dies and those run on the Extrusion Press can be processed effectively and quickly, without handwork. All bearing surfaces, even those inaccessible with hand tools, are processed uniformly by the viscous but free-flowing AAFM Media, that acts as a "Flowable File" as it is pumped through the Die profile(s) (Read article)


BILLET AND BLOCK LUBRICATION BEST PRACTICES

James E. Dyla, Amcol Corporation, USA

Abstract

Dummy block lubrication has changed significantly over the years with the inception and evolution of the fixed dummy block and the integration of hot log shears and saws. More recently, there has been an emphasis on safety which has led to the elimination of the popular acetylene sooters and the complete guarding of the extrusion press. Of course, there is the constant passion to improve productivity, reduce downtime, and increase recovery. Two technologies have come to the forefront to spray lubricate either the back side of the billet or the dummy block directly. The first is Boron Nitride based ceramic powders which are electrostatically applied and the second is Water Based Organic Polymer solutions which are air atomized. Both are designed to completely eliminate manual lubrication and fully automate the process. Both have advantages and disadvantages. Further, both technologies have evolved over many years in order to improve reliability and reduce overuse of lubricant and the subsequent overspray. This article will attempt to provide a brief, yet thorough, comparison of both technologies and explore best practices in use. (Read article)

 

Magazine 2013/4

PRACTICAL IMPLEMENTATION OF NUMERICAL MODELING TO OPTIMIZATION OF EXTRUSION DIE DESIGN FOR PRODUCTION OF COMPLEX SHAPE PROFILES

Nikolay Biba, Sergei Stebunov, Andrey Lishny, QuantorForm Ltd., Moscow, Russia

ABSTRACT
The paper presents the experience of aluminium profile extrusion simulation using QForm-Extrusion program. Due to non-uniform material flow the profile that leaves the orifice may bend, twist or buckle. The goal of the simulation is to predict this undesirable shape deterioration and to find ways to minimize it. The program has special interface for fastest die geometry import. The program automatically finds bearing zones and converts them into parametric form allowing modification of bearing design without return to original CAD model. Alterations and optimization can be done by using a special module “Bearing Editor”. In turn with simulations the user can modify die design to achieve the most uniform distribution of longitudinal velocity. The simulation also provides comprehensive analysis of the tool stresses and deflection taking into accounts all the components of the tool assembly. Coupled simulation mode allows to analyse the influence of the die deflection on the material flow and to compensate this effect. The software is in use at many die making and extrusion companies showing its high economic efficiency. (Read article)


AN UNDERSTANDING OF FLOW STRESS IS FUNDAMENTAL TO INCREASING PRODUCTIVITY

Paul Robbins, Castool Tooling Systems, Canada

ABSTRACT
In discussing the evolution of the now maturing extrusion industry, there is a basic truth which should always be considered. The productivity of every extrusion plant can be improved. There are no exceptions to this rule. The single uncontrollable limiting factor in the quest for increased productivity is the maximum speed at which the metallurgy of the alloy being used will permit it to form saleable product with the required profile. Everything else in the entire production system is now controllable.
The technology of light metal extrusion has improved considerably in the past few years. With both die design and production systems increasingly being digitized and improved, extruders can now provide profiles with a level of complexity, dimensional tolerance and surface finish that was unknown just a few years ago. The ability to understand flow stress, as well as new equipment such as automated die heating systems, and improved single cell die ovens have contributed to the developing maturity of the extrusion industry (Read article)

 


Magazine 2013/3

CHARACTERIZATION AND MODELING OF THE DEFORMATION AND DAMAGE BEHAVIOR OF THICK-WALLED ALUMINUM PROFILES

D.-Z. Sun, A. Ockewitz, G. Falkinger, F. Andrieux
Fraunhofer Institute for Mechanics of Materials IWM Freiburg, Germany

ABSTRACT
Extruded aluminum profiles show a pronounced anisotropic deformation behavior and inho-mogeneous properties over thick-ness and for different wall thick-nesses. In vehicle simulations shell elements have to be used due to computer capacity whereas the
applicability of shell elements for thick-walled components has not been verified. Since fracture strains of aluminum profiles are relatively low, damage modeling has to be included in component simula-tions. However, it is not clear, which damage model can be used in these cases and which specimen tests have to be performed to cali-brate the model parameters. (Read Article)


STRESS ACCELERATED TEMPERING OF HOT WORK STEELS AS A FAILURE MECHANISM IN ALUMINUM EXTRUSION TOOLING AND DIE CASTING DIES

Joseph C. Benedyk and Philip NashThermal Processing Technology Center
Illinois Institute of Technology, Chicago, Illinois, USA

ABSTRACT
Conventional tempering curves (isothermal curves of hardness vs. time) for steels that have been austenitized and quenched to
form martensite essentially provide information on tempering behav-ior at tempering temperatures with zero stress applied. At the same time, in hot work tooling used in aluminum extrusion and dies used in high pressure die casting, the die steels in the quenched and tem-pered condition, are subjected to stress and temperature, begging the question of what is the effect of stress and temperature combined on these dies and tooling during application. A significant history of stress accelerated tempering of a variety of hot work steels has been established in various types of tests conducted under special-ized thermal fatigue and creep
testing conditions. (Read Article)


Magazine 2013/2

AUTOMATIC CLEANING OF EXTRUSION DIES

Massimo Masiero, Italtecno, Modena, Italy

(Read Article)

NONDESTRUCTIVE EXAMINATION OF EXTRUSION PRESS HYDRAULIC CYLINDERS

(Read Article)

GLOBAL ALUMINIUM APPLICATIONS IN ELECTRIC VEHICLES AND CHARGING INFRASTRUCTURES

(Read Article)


Magazine 2013/1

NEXT GENERATION OF CONTINUOUS HOMOGENIZING PLANTS, PROCESS FLEXIBILITY

J. Talerzak, Seco/Warwick ThermAL S.A., Poland

Abstract
When discussing the area of ho-mogenizing in general and con-tinuous homogenizing in specific, the general idea has been that the continuous homogenizing oven produces a lower but still a more consistent quality than batch homogenizing. This ena-bles the extrusion press mana-gers to set their press speed at a higher level as the metallurgical properties in the metal are more or less equal between billets.

(Read Article)

OPTIMIZING DIES WITH ADVANCED TECHNICAL TOOLS

T. Andreoli, Phoenix International Spa, Italy

Abstract
Everybody knows that aluminium usage is extremely wide -spreaded all over the world. This scenario has been reached mainly thanks to this material’s characteristics, but most of all with a complete set of techni-cians and experts that put their
effort to improving it: various e-xamples are refiners and end users, extruders and die makers.

(Read Article)


Other Magazines

FURNACE ENERGY SAVING MYTHS

The approximate cost of these ideas for aluminum melting and holding furnaces will be presented...

David W. White, The Schaefer Group Inc., USA

(read article)


RESPONDING TO TECHNICAL REQUIREMENTS FOR EXTRUSION CONTAINERS AND STEMS

G. Strehl, S+C Extrusion Tooling Solutions, Germany

Germany

(read article)


LARGE DIAMETER BILLET CASTING WITH WAGSTAFF® ARC™ CASTING TECHNOLOGY AND ABB EM STIRRING

Tim Scott, Research Metallurgist, Wagstaff, Inc.
Christer Carlsson, Area Sales Manager, ABB

Introduction
Wagstaff, Inc. has been involved with billet casting technology design for many years with sizes typically below 530 mm diameter. Interest in increased billet diameters recently induced a fresh look at the need to cast a wide range of alloys in extended sizes. The intent of the Wagstaff® ARC™ (Advanced Refractory Channel) Large Diameter Billet Technology development is to push the boundaries of current market capabilities.

To date development has been primarily focused on casting the challenging 2XXX and 7XXX alloys with the ARC mold. First production tooling has been manufactured and shipped to be commissioned this year.

To broaden the benefits to the casthouse, a parallel research project was established to investigate the effect of Electro Magnetic (EM) stirring as an additional method to increase value to end users of large diameter billets produced with ARC Technology.
Wagstaff, Inc. provided the casting tooling and casting expertise, while ABB provided the modeling, electromagnet and power supply control for the stirring.
 

THE ALUMINIUM INDUSTRIAL SYSTEM AFTER THE CRISIS

Mario Conserva, Alfin-Edimet Spa , Brescia, Italy

Abstract
The global aluminium market has heavily felt the effects of the recent global crisis; after years of uninterrupted growth, the demand experienced its first negative signs in 2008, with a consistent further decrease followed into 2009, for the expected return in 2010 to a relative growth trend.

The evolution of the crisis confirmed changes in the barycentre of aluminium production and demand, a process which has been under way for at least 10 years and is determined by the differences in energy costs, relative maturity of the markets and by the interesting growth potential of light metal in developing countries.
A key aspect of the aluminium value chain is the question of energy; the long term supply of electricity at a competitive price on an international level is a matter of priority for the production of primary aluminium.

 (read article)


EFFECT OF LENGTH VARIATION ON DISTORTION MODE DURING COOLING PROCESS IN ALUMINUM EXTRUSION SIMULATION

S. Bikass1, B. Andersson2, A. Pilipenko2
1 University of Oslo – Faculty of Mathematics and Natural Sciences –Norway
2 SINTEF – Materials and Chemistry – Norway

(read article)


A COMPARISON OF ALUMINUM AND PVC WINDOWS MANUFACTURERS BUSINESS MODELS

Carmine Garzia, USI, Università della Svizzera Italiana, Switzerland


(read article)


MANUFACTURING OF DISCONTINUOUS STEEL-REINFORCED
ALUMINUM PROFILES BY MEANS OF CO-EXTRUSION


Matthias Haase, Daniel Pietzka, Nooman Ben Khalifa, A. Erman Tekkaya
Institute of Forming Technology and Lightweight Construction (IUL),
TU Dortmund University, Germany

(read article)


HOW GLOBALIZATION IS CHANGING COMPETITION
IN THE ALUMINIUM INDUSTRY INDUSTRY


Bruno G. Ruettimann, Consultant

(read article)


QUALITY DEFECTS THAT ARE NOT ACCEPTABLE

...It is a general concept in extrusion industry that the press is not productive when extruding scrap...


Srimay Basu, Dubai Aluminium Company Limited, Dubai, UAE


(read article)


THE ULTIMATE EXTRUSION TOOLING SYSTEM
FOR MAXIMUM RAM SPEED AND MINIMUM UNSCHEDULED

...Maximum saleable product with minimum unscheduled do-wntime is the goal of every e-xtruder because...


Paul Robbins, Castool Tooling Systems, Canada

(read article)

 


INCREASING DOMESTIC MARKET DEMANDS AS THE MAIN DRIVER FOR THE SUSTAINED DEVELOPMENT OF CHINA’S ALUMINIUM INDUSTRY IN THE PAST AND IN THE FUTURE

...China has become the largest aluminium producing and consuming country in the world...


Zitao Wang, Lw Aluminium Processing Technology Service Centre, Guangdong Non-Ferrous Metals Society – Processing Academic Committee, Guangzhou, China

Jie Zhou, Department of Materials Science and Engineering, Delft University of Technology, The Netherlands

(read article)


N5NITROGEN
ELIMINATION OF EXTRUSION DIES OVERHEATING BY USING LIQUID NITROGEN TECHNOLOGY

The use of liquid nitrogen on extrusion process allows big speed increases (from 10% up to more than 50%) but, in order to reach such results, it is required an easy and safe management of the whole process...


Massimo Bertoletti, A.t.i.e. Uno Informatica, Italy

(read article)


STATE-OF-THE-ART OF INTEGRATION


Massimo Bertoletti, A.t.i.e. UNO Informatica, Italy

(read article)


GREATER ECONOMY IN THE EXTRUSION OF ALUMINIUM SECTIONS

The use of nitrogen for improving output and quality in the extrusion of aluminium has been widely adopted today...


Giampiero Valenti, Messer Italia SpA, Italy - Thomas Böckler, Messer Group GmbH, Germany

(read article)


ANALYSIS OF SOME PROCESSES OF INTENSIVE PLASTIC DEFORMATION (IN CONFORMITY WITH INDUSTRIAL CONDITIONS)

The present paper covers both well-known and new techniques of intensive plastic deformation applied for an increase in the number of microslips and refining of grain size in a structure of aluminium alloys, to obtain...

Vadim L. Berezhnoy , All-Russia Institute of Light Alloys (VILS Stock Co.), Russia

(read article)


PROPERTIES OF 2XXX ALUMINUM EXTRUDED RODS BOTH IN T3 AND T8 TEMPERS

Extruded products made from 2XXX aluminum alloys nowadays are used for various applications...One of the most common semi product made from these alloys are rounded extruded rods...


Igor Duplančić, Jere Prgin, Zoran Bračić, Siniša Junaković
Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, University of Split, Croatia, TLM Inc., Croatia

 (read article)


EXPERIMENTAL STUDY OF LONGITUDINAL WELD-SEAM PROPERTIES IN HOLLOW EN-AW 6060 AND EN-AW 6082 ALUMINIUM ALLOY EXTRUSIONS

...For the successful application of structural extruded products, the mechanical integrity of the longitudinal weld seams is thus of paramount importance.
This paper presents the results of laboratory extrusion trials with the EN-AW 6060 and EN-AW 6082 aluminium alloys...

A.J. den Bakker, W.H. Sillekens, E. Meijersc
Nedal Aluminium B.V. - TNO Science and Industry - Netherlands Institute for Metals Research - The Netherlands

(read article)


DOUBLE PULLER SYSTEMS. WHICH ONE TO CHOOSE?

Extrusion technologies have had during the last years constant updating giving the market several options and solutions to improve productivity and quality...


M. Spizzo - OMS impianti Italy

(read article)


FURTHER GLOBALISATION OF THE ALUMINIUM INDUSTRY AND STRATEGIC DILEMMAS OF LOCAL PRODUCERS OF SEMIS

Trends shaping the world and the aluminium industry in the 21st century are the economic strength of East Asia and increasing vulnerability of the Western World concerning energy, raw materials and its economic deficit. The rapid growth of production and consumption of primary aluminium in China...


V. Kevorkijan, Impol Aluminium Industry, Slovenia

(read article)


MAXIMISING THE PRODUCTIVITY OF ALUMINIUM EXTRUSION WITH NITROGEN

Several methods of introducing the liquid nitrogen are described. Results are presented for each and the advantages of each technique are discussed...


Paul Stratton, BOC and Chong Ee Sung, MOX, Great Britain

(read article)


INNOVATIVE TUBE EXTRUSION PLANT FOR ALUMINIUM ALLOYS

Modern tube presses are characterized by a clear and readily accessible arrangement of the required auxiliary devices...


Axel Bauer
SMS Eumuco GmbH, Leverkusen, Germany

(read article)


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