The toolmaker Siebenwurst uses injection molding simulation to optimize part design and production processes in its routine workflows. Among other things, Simcon’s software ensures the quality and dimensional accuracy of the plastic frame for the first series-produced injection molded e-bike.

Controlling Complex Development and Manufacturing Processes, Using Simulation

Spritzgießen

Kunststoffverarbeitung: Verfahren

Composite-Halbzeuge

Halbzeuge und Zwischenprodukte

Kunststoff-Halbzeuge

Spritzgießwerkzeuge

Kunststoffverarbeitung: Maschinen und Komponenten

Werkzeuge für die Kunststoffverarbeitung

Verbundwerkstoffe / Werkstoffverbunde

Kunststoff Werkstoffe

Dienstleistungen

Werkzeug-, Formen- und Modellbau

Spritzgießsimulation

Software

Simulation

A Bike Frame from an Injection  Molding Machine

Marbling is often a real eye-catcher in plastic components. However, the effect is difficult to create and there are some pitfalls when it comes to reproducibility. Novel nozzles for injection molding machines in combination with a special dosing technology allow marbled molded parts to be produced far more easily in a much more robust process.

A 3D-Printed Nozzle and Modified Dosing Method Deliver Reproducible Marbling  in a Robust Process

Kunststoffe

Photonik

Optik

Additive Fertigung

Farben, flüssig

Additive

Exciting Design instead of  Exciting Manufacturing

Hybrid production chains have been increasingly in the spotlight in recent years. This also applies to the combination of conventional manufacturing and additive processes in tool construction. With the example of an injection molding tool, it is shown how mold inserts produced by additive manufacturing can greatly shorten cycle times, and thereby significantly reduce unit costs. The important thing is to find a suitable combination of processes from the variety available.

Additive Manufacturing and Hybrid Molds in Combination with Conventional Machining

HSC- / HPC-Bearbeitung

Spanende Verfahren

Werkzeugkonstruktion

Anlagen Additive Fertigung / 3D-Druck, Metall

Anlagen für die Additive Fertigung

The Potential of Redesign and  Part Consolidation

Anyone seeking to replace a metal component by a plastic one, to reduce the number of component parts from eight to three and simultaneously cut both the weight and manufacturing costs needs to take great care to ensure that all specifications are met – especially if the component is used in a hot gearbox and is subject to high mechanical stress.

Production-Ready Plastic Shifter Fork Offers a Maximum of Functional Integration

Kohlenstofffasern / -matten

Verstärkungsstoffe

Produktentwicklung (F+E)

Innovationsentwicklung

Wirtschaft

Innovationen und neue Technologie

Inserttechnik

Hybrid-Spritzgießen (Metall / Kunststoff)

Replacing Metal in the Gearbox

Starting with the systematic design of manufacturing processes and the precise simulation of part manufacture, through smart tooling technology and sophisticated melt guidance, to efficient mold temperature control, numerous exhibitors have many innovations in the field of tooling technology on offer at K 2019.The current debates concerning marine pollution as well as anthropogenic climate change and its consequences seem to be having an effect at this world-leading trade show for plastics processing in Düsseldorf, Germany. A number of companies are noting the growing customer interest in sustainable, carbon-neutral and resource-efficient modes of production, and offering products and services intended to satisfy this interest.

Resource-Efficient and Environmentally Friendly Products Are the Trend in  Tooling Technology

Werkzeuginnendrucksensoren

Messtechnik

Sensoren / Messwertaufnehmer

Temperiergeräte

Gießanlagen

Temperiertechnik

Normalien für die Kunststofffertigung

Normalien

Heißkanalsysteme

Komponenten für die Kunststoffverarbeitung

Kaltkanalsysteme

Exhibitors See Green

Once again, the K 2019 in Düsseldorf, Germany, lived up to its claim to be the leading trade show for plastics technology. At least in the field of injection molding, there were exciting global innovations to see – if you looked closely.

Injection Molding Trends at K 2019

Schaumspritzgießen

Smart Factory

Energieeffizienz

Mikrospritzgießen

Mehrkomponenten-Spritzgießen

Spritzgießmaschinen, allgemein

Spritzgießmaschinen

Fließpressen

Handling, Handhabungstechnik für die spanende Fertigung

Automatisierungstechnik

Handling, Handhabungstechnik

Spritzgieß-Sonderverfahren

Elastomer-Spritzgießen

Linearroboter für die Kunststoffverarbeitung

Industrieroboter

Montagetechnik

Industrie 4.0 für die Kunststoffverarbeitung

Industrie 4.0

Montage-Spritzgießen

Knickarmroboter

Co-Injektion (Barriere-/Sandwich-Spritzgießen)

Ressourcenmanagement

Produktion

Technical Excellence thanks  to Digital Assistance

Flexflow is an innovative, servo-driven, finely adjustable valve gate system for cascade injection molding. Especially with large-format parts as are used in the automotive industry for interior and exterior applications, the technology can be used to attain significant improvements in the surface quality of the part while reducing the required clamping force and even the part weight. It also avoids the dreaded pressure marks on the molding that often occur with the cascade injection molding process. 

The Italian Hot Runner Specialist HRSflow Focuses on the Quality of Large-Format Parts 

Steuern, Regeln

Normalien und Heißkanaltechnik

Intelligently Controlled Cascade  Injection Molding  

A recently developed variant for processing continuous fiber-reinforced semi-finished products by injection molding, involves positioning a defined number of UD laminates appropriate to the specific requirements in the mold and then overmolding them. The resultant lightweight, three-dimensional parts have rigidity and strength which are markedly anisotropic and optimized for their particular loading situations. 

UD Tape Reinforcement Minimizes Weight while Maximizing Local Loading Capacity 

Greifer

Faserverarbeitung

Werkstoffprüfung, mechanisch

Zug-und Druckfestigkeitsprüfgeräte

Having a Good Grip on Hot Laminates  

At the K 2016 in Dusseldorf, Germany, four project partners demonstrate the end-to-end networked process chain from the product development, simulation and the design of the sensor-fitted tool to testing the first sample on the injection molding machine and finally manufacturing within interconnected production. Thanks to the transparency of this process, the partners are able to set the production course toward the overriding principles of the production concept ‘Industry 4.0’.  

Interconnecting all Elements of the Value Chain from the Product Idea to Injection Molding in the Production Line 

Thermographie

Druck- / Kraftsensoren

Produktentwicklung(sprozess)

Finding our Way through the Labyrinth 

"Think of it like this: the clip is bent when it leaves the machine, and you can see it straightening as it cools", states Georg Schlöser. "And that is how we calculated it", he adds satisfied, since he analyzed the required shrinkage allowance with Sigmasoft, so that the mold could deliver dimensionally true parts from the first shot.  

With Sigmasoft Virtual Molding, F. & G. Hachtel Manufactures Accurate Parts from the First Shot  

Qualitätssicherung

Getting Warpage under Control  

Bielefeld University of Applied Sciences has succeeded in developing an injection mold that does not require conventional liquid-based temperature control. Heat equalization is effected by means of heat pipes instead. Mold design and heat-pipe selection are based on the outcome of thermal simulations, which yield reliable results thanks to an unconventional approach. 

Simulating Heat Flow in Injection Molds with Heat Pipes 

Prozesssimulation

Kupfer

"No Cool" Molds, Properly Simulated 

To be able to cost efficiently design complex molds, e. g. for BMC components, it is essential to take into account the mold cooling. Thus, the mold costs increase in a linear relationship with the number of heating cartridges provided. It is therefore desirable to aim for as few cartridges as possible, but at the same time, this can have a disadvantageous effect on the homogeneity of the temperature distribution and the robustness of the process. Until now, these conflicting goals were largely resolved based on experience. But it can also be done systematically. 

Simple Answers to Complex Questions in Mold Design 

DOE-Software

Determining the Optimum Heating Concept for BMC 

The optimization of injection molding processes by using software to simulate mold filling and solidification is standard today. However, this has its limits, especially if the material properties or the flow behavior are not known with sufficient accuracy. The services offered by Beaumont, such as material testing, injection molding tests or the optimization of flow channel systems, can help here.  

MF Software Exclusively Distributes Beaumont Products in Europe 

Werkstoffprüfung

Rheologie

Higher Productivity and Better  Process Control 

Users can now precisely simulate and design the mold temperature control already at the planning phase. 

Cooling Simulation with Temp-Flex Hoses 

Precise Simulation of Thermal Behavior 

Susanne Schröder will become editor-in-chief of the magazines Kunststoffe and Kunststoffe international on December 1, 2020. The current editor-in-chief Dr. Karlhorst Klotz will leave the company by mutual agreement.

Werkzeuge für Leichtbauwerkstoffe

Präzisionswerkzeuge

Tiefziehwerkzeug

Werkzeugüberwachung

Toolmanagement

Werkzeugwechselsysteme, Spritzgieß

Werkzeug- und Formenbau

Modulare Werkzeugsysteme

Absaugungen für Werkzeugmaschinen

Betriebsausrüstung / Betriebsmittel

Absaugvorrichtungen

Fluorkunststoffe

Thermoplaste

Werkzeugverwaltungssoftware

Prüfen von Kunststoffen

Biokunststoffe

Presswerkzeuge, Kunststoff

Werkzeugreinigung, Kunststoffe

Standardkunststoffe

Kunststoffverarbeitung

Lohnfertigung

Technische Kunststoffe

Füllstoffe für Kunststoffe

Kunststoff

Bauwesen

Baustoffe

Kunststoffhandel

Handel

Betriebstechnik für Kunststoffverarbeitung (Peripherie)

Kunststofffasern

Kunststoff-Recycling

Kunststoff-Aufbereitung

Hochleistungskunststoffe

Qualitätssicherung Kunststoff

Change in the Chief Editorial Office of Kunststoffe

“You Can See What Is Happening  in the Mold”

Interview with Eberhard Duffner and Paul F. Filz by the Magazine Kunststoffe

The 2019 K fair focused on the fusion of digital methods with analog production processes. At the fair, Arburg and Simcon showcased a filling process proceeding in real-time, as a 3D animation, on the display of a machine control panel, for an example of sunglasses, made of PA12. All that was needed to prepare this, was to load the simulation model, as well as the geometry of the part, directly onto the machine controls. This sounds almost too easy to be true. Right?

At the 2019 K fair, Arburg and Simcon showcased a filling process proceeding in real-time, as a 3D animation, on the display of a machine control panel, for an example of sunglasses, made of PA12. All that was needed to prepare this, was to load the simulation model, as well as the geometry of the part, directly onto the machine controls. This sounds almost too easy to be true. Right?

The dream of using simulation results directly on injection molding machines has been around for decades – and has always interested Eberhard Duffner. He had already been head of development at Arburg and head of the advisory board of the injection molding section at the Institute for Plastics Processing (IKV) in Aachen, Germany, for some time, when he had a remarkable experience: “I asked, who is using simulation, and all hands went up in the circle of machine manufacturers. I then asked, who has tried to transfer these simulation results directly into basic machine settings – and this time, those same hands stayed down. I was surprised.” So: how is it possible, that, in this day and age of digitization, injection molding machines still know so little about the mold and the part? “Somehow”, Duffner thought, “it should be possible to take scientific insights from the IKV advisory board and apply them at Arburg. We discussed these ideas a lot: is it possible, today? How can we do it? These questions marked the beginning of the collaboration between Arburg and the simulation software experts at Simcon.

Kunststoffe: Mr. Duffner, Arburg and Simcon showcased a filling simulation, directly implemented on an injection molding machine, at the K show in 2019. What’s the main idea underpinning this solution?

Duffner: First, we want to simplify the job for machine setters. They should not have to analyze curves to get optimal mold filling. The fact that set curves don’t directly translate to the real process is something I also experience during trials, and in the production of molded parts in our customer center. Our goal is that the setter need not observe the screw stroke or the pressure profile over time. Instead, we want to visualize the filling process in 3D on the machine, and show how it changes, depending on the parameters. This means you need to have a simulation on the machine. And that is the first stage of the filling assistant, which we have implemented from the simulation.

Kunststoffe: And what’s next?

Duffner: Next, we want to focus on helping our users to solve quality issues. In order to do that, we need to demonstrate the process fluctuation in a modern, interactive, three-dimensional visualization. In this way, the machine setter can see what is happening inside the machine, without needing to interpret an abstract scientific curve. That is the challenge.

Kunststoffe: Mr. Filz, that sounds like it makes sense. Why is there still a gap between product development and production in injection molding?

Filz: Mainly for historical reasons: in simulation, people have typically thought in terms of physical process variables of the melt, like the volumetric flow rate, filling times, or packing pressures. But injection molding machines are set up with different kinds of parameters, like screw advance speeds, screw strokes, changeover points and so on. These approaches basically achieve the same thing, but it is not easy to convert into one another. So, in a nutshell, things get lost in translation between engineering and production.

Kunststoffe: What would you estimate: what share of companies use a filling simulation nowadays, when they are designing molds?

Filz: We estimate that about 25 percent of companies use simulation systematically during product development. In those 25 percent, I’m counting the companies who actually simulate in-house, not companies that only order a simulation as an external service every once in a while, when they have a particularly complex part.

Kunststoffe: Considering those numbers: isn’t integrating the filling assistant like taking the second step before the first?

Filz: No, certainly not. We want to make results from engineering easily accessible to the injection molding machine user, to help close that gap between production and engineering. Production practitioners often claim that real-life results don’t match what engineering has sent them. And it’s easy to see why: something about the mold was modified in the interim, or a process is run differently from what was anticipated in engineering – usually, for good reasons. So, there is a disconnect between the engineering plans and the practical implementation. That’s why it makes sense to take a more integrated approach, with a filling assistant that’s right there, on the machine. Because that way, you can better ensure that those two things match.

Kunststoffe: So you would prefer there to be feedback loops with reality?

Filz: Yes, clearly, we want that matching to happen. In many cases, people on the front lines aren’t feeding those real-life observations back to engineering. This of course makes it difficult to see how well the results were realized on the injection molding machine. When people observe how well reality and the simulation results correspond if the settings match, the benefit becomes clearer. And this will continue to increase adoption of using simulation as a tool. As a result, we will eventually go way beyond the 25 percent usage rate that I just mentioned. There is still an incredible amount of untapped potential out there, and this is something that really helps customers realize and capture that value.

Kunststoffe: How are the on-screen animations linked to the real processes on the machine?

Duffner: You can see in real time what is currently happening in the mold, as a live filling image displayed on the machine control screen. To bring these two things together, we compute a simulation model, which is parameterized and fully integrated into the Gestica control. The animations are then shown, synchronized with the injection process on the machine. Not only that, we also use parameters from the simulation, such as dosing volume, temperatures and pressures, as presets for the machine. On the screen, the mold filling then does not simply run linearly over the screw path, but is also linked to the compressibility of the melt and the closing behavior of the non-return valve.

Kunststoffe: That is, you could also use the screen to better understand partial filling behavior?

Duffner: Yes, if we stop the injection process at a certain point, say 90 or 95 percent for a filling study, then the part from the machine should look like the simulation results displayed in the filling assistant, with a certain accuracy. That is the first function that we’ve integrated: a regular sample filling study. As of today, this may not yet be precise enough for all classes of molds. But it works well with the kinds of molds with which we have already tested it. We need to address this openly – otherwise we cannot win the acceptance of the machine setters.

Kunststoffe: Which kinds of tools or geometries have been left out, for the time being?

Duffner: We are quite comfortable with a mold with a cold runner gate and a certain number of cavities. I wouldn’t put a 96-cavity screw cap mold in this category, because the hot runner volume is three times the shot weight, and compressibility has a massive effect.

Filz: Such multiple-cavity molds involve considerations that are not yet tackled in the simulations. A very large hot runner with lots of branches, for example, has a life of its own in terms of how it is controlled, and that is not yet taken into account by the simulation. The simulation assumes some standard conditions. But as long as those basic requirements are met, you can reliably use simulations of the type that will be available on the Arburg machine, for both simple and more complex components.

Kunststoffe: What about materials?

Filz: Here, too, at this time there are still some restrictions, as we have not yet been able to test everything down to the last detail in the short time before the K show. We are now doing this step by step, so that we will have comprehensive coverage for the filling assistant.

Kunststoffe: What does the interface between machine and simulation look like?

Filz: One advantage of simulations is, that there is basically only one variant. If, for example, we were to specify an injection volume flow profile as a bar, it would work wonderfully, because there would be no mass and no control valves that needed to be regulated in some way. What is a bigger challenge, is for Arburg to take the information from the simulation, and translate them so that they are implemented physically on the actual machine.

Duffner: We complement each other and of course we have to create translations between several different software interfaces. For example, let’s say you’ve got a flow rate profile with a few discrete jumps. But the machine can’t do discrete jumps, and may not be able to achieve the targeted maximum speed. In such cases, we compute normalized profiles, for example by adjusting the total injection time, to translate it into something that is feasible in practice, on the machine. But that’s not all: we have to transfer the model to the respective machine with its specific gear and configuration, i. e. implement it in the real physical environment. This changes the model, possibly impacting quality, and you have to take a step back in the model creation process. So, this is a recursive process – and a lot of hard work.

Kunststoffe: Mr. Duffner, you said earlier that you transfer some parameters from the simulation into the process. Which parameters are those?

Duffner: With Arburg, development is based on the principle “machine knows part” – i. e. it knows itself and its special equipment, and it knows the molded part. The machine gets its 3D geometry from the filling simulation, so it knows the shot volume and can calculate the metering volume, taking into account the screw speed, the pvT curve and the nonreturn valve parameters. For certain materials, we have stored settings that can be obtained through the material selection. And we have a clear philosophy for the changeover point, which is set at 98 percent filling.

Filz: Arburg takes all of the results from a regular simulation, such as temperature settings for the melt or the injection volume flow profile, and converts them into what the machine needs. It’s really a symbiosis of what we can do in the simulation and what Arburg are able to do with their know-how, to influence the behavior of the machine so that realizes the optimal simulation results.

Kunststoffe: The original focus of simulation is actually to calculate shrinkage and warpage, right?

Duffner: Yes, that has been in focus. And we will also take this aspect into account in the future, in order to optimize the parameters for this. But right now, we’re prioritizing other aspects. If you want to support a machine setter efficiently, you’ve got to focus different things than when you are supporting the part designer who uses simulations for tool design. Today, it still takes too long to calculate the full simulation inline on the machine itself. Solving this requires close cooperation, understanding from both sides and a willingness to constructively deal with failures along the way. Because it’s less useful if you’ve got time to go get a coffee while the machine is running the calculations for a simulation model. Our goal is for the 3D representation to run in real-time.

Kunststoffe: What do you think: will your customers embrace the filling assistant?

Duffner: The filling assistant is an essential tool for sampling, for the mold designer – provided that the results are reliable, and the machine setter can trust their accuracy. This is our first priority. Of course, this what we believe. For example, let’s take a technical part with leaps in wall thickness. In order to fill this part with a constant flow front speed, as theory would suggest, you’ve got to accelerate at thicker points and reduce speed at thinner ones. Up to now this has been a black box for the setter. With the filling assistant, on the other hand, they can see exactly when a jump is coming, and can respond accordingly. Running a simulation gives you mathematically rigorous results, based on the geometry of the part and the volume flow profile. The setter doesn’t need to guess anymore.

Filz: Above all, you need to eliminate transfer errors, which happen because things are lost in translation between engineering and the machine operator. If the operator obtains the basic settings in an automated way, that helps. Efficiency automatically increases, because setup times are reduced, and typical ambiguities and translation errors can be avoided. It’s like having a car navigation that considers traffic jams and thus avoids unnecessary stress. This makes it much less likely that the machine setter will be woken up by a WhatsApp in the middle of the night because a machine is at a standstill.