Over past months, many in-house workflows and development processes have slowed down and also changed. Nevertheless, time has not stood still, also not in injection molding technology. The debate and development have been shaped by two themes: digitalization and the circular economy. Below are some examples of developments and projects that underpin this trend.

Two displays are seamlessly integrated into the continuously 3D-formed instrument panel

Innovative Injection Molding in Times of Pandemic

Spritzgießen

Kunststoffverarbeitung: Verfahren

Schaumspritzgießen

Künstliche Intelligenz für die Qualitätssicherung

Industrie 4.0

Industrie 4.0 für die Qualitätssicherung

Steuern, Regeln

Software

Mehrkomponenten-Spritzgießen

Folientechnik (IMD, IML, FIM, u.a.)

Digitale Transformation

Wirtschaft

Innovationen und neue Technologie

Spritzgießwerkzeuge

Kunststoffverarbeitung: Maschinen und Komponenten

Werkzeuge für die Kunststoffverarbeitung

Biokunststoffe

Kunststoff Werkstoffe

Spritzgieß-Sonderverfahren

Nachhaltigkeit

Umweltmanagement

Spritzgießsimulation

Simulation

Schnecken und Plastifiziersysteme

Spritzgießmaschinen

Industrie 4.0 für die Kunststoffverarbeitung

Machine Learning / Künstliche Intelligenz für die spanende Fertigung

Industrie 4.0 für die spanende Fertigung

Kunststoff-Recycling

Kunststoff-Aufbereitung

Lasermarkieren

Oberflächentechnik

Laserbearbeitungen

Inline- / Online-Messsysteme

Qualitätssicherung

Qualitätssicherung Kunststoff

Kreislaufwirtschaft

There Is More beyond the Horizon

In contrast to recent years, when particular key themes often dominated the fair exhibits of the leading injection molding machine builders, this year’s Fakuma will present more combinations of many different competences in complex production cells. Thus, Industry 4.0 not only takes slowly concrete shape, but is put into context with peripherals and controls in the development of new series. 

Re-Inventing Injection Molding Holistically  

Servomotoren

Handling, Handhabungstechnik

Instandhaltung, Wartung in der spanenden Fertigung

ERP-Systeme

Polyurethan

Additive Fertigung

Gasinjektionstechnik

Temperiertechnik

Reinraumsysteme / -technik

Machines as the Heart of Production 

With special mold technology and process control, it is possible to produce parts with locally highly foamed structures. The foam can considerably extend the limited design freedom of compact molded and conventionally foamed parts. Hence, extremely abrupt changes in wall thickness can be achieved and conventional design guidelines for ribs circumvented. Variothermal process control ensures excellent surfaces here. 

Process Variant of Foam Injection Molding Opens up New Lightweight Construction Potential 

Customized Foam 

The announcements in the field of injection molding give the impression that the developments of recent years are continuing. These include the increasing digitalization of injection molding production, as well as highly integrated production cells that combine very different competencies. The spotlight shines not only on the machinery, but rather on optimum system solutions for integrating molds and individually configured peripheries in the digital and the real world. 

Fakuma 2018: Injection Molding Networked and Integrated 

Steuerungen (Hardware und Software)

Treibmittel

Spritzprägen

Elastomer-Spritzgießen

The Communicative Machine 

Making a racket is part of the trade. In the past, tradesmen would do this at markets by swinging wooden rattles to attract attention. Today, instead, it is the industry which is trying to make its developments heard and accepted, for example at trade fairs and in the media. What has injection molding technology had to offer recently, aside from Industry 4.0? The answer is process developments that in the main expand the range of applications for plastic parts, mechanical assistance systems that enable consistently high part quality to be achieved more reliably, and the huge field of temperature control. 

New Ways to Attain Special Part Properties Are Advancing the Art of Injection Molding 

Verbundwerkstoffe / Werkstoffverbunde

Making a Racket for Plastics  

Flexibilization of production, lightweight design, functional surfaces, increasing product customization, consistently low reject rates etc. ¿ the OEM wish list is becoming longer and longer. While the OEMs are the main drivers in the injection molding segment, their mounting demands are challenging Tier 1 suppliers, mold makers and systems suppliers alike. For an interview, we met with specialists from GKTool and HRSflow, for whom the search for new solutions is daily routine. The topic is integration ¿ of ideas, processes and system partners. 

Christian Götze (GKTool) and Moreno Carvani (HRSflow) about Cost-Efficient Production through Integrated Mold Technology 

Normalien und Heißkanaltechnik

"With System Integration,  Fewer Errors Occur" 

In addition to excellent mechanical characteristics and suitability for recycling, the key feature of hybrid lightweight structures made of fiber-reinforced thermoplastics is that automated, large series production is possible. New mold and process technologies were successfully developed within the scope of the ReLei research project, enabling the production of complex shaped sandwich elements in an efficient combined process.

In the ReLei project, several research and industry partners developed a rear shelf based on a fiber-reinforced polyamide as an example for manufacturing a complex sandwich structure

Thermoplastic Sandwich Structures for Large Series Applications

Fasern

Halbzeuge und Zwischenprodukte

Kunststoff-Halbzeuge

Faserverarbeitung

Industrieroboter

Montagetechnik

Faserverbundwerkstoffe

Andere Werkstoffe

Making It Big with Small Bubbles

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.

Fig. 1. Smart Operation – the machine is operated with only four buttons (© KraussMaffei)

Injection Molding Trends at K 2019

Smart Factory

Energieeffizienz

Mikrospritzgießen

Spritzgießmaschinen, allgemein

Fließpressen

Handling, Handhabungstechnik für die spanende Fertigung

Automatisierungstechnik

Linearroboter für die Kunststoffverarbeitung

Montage-Spritzgießen

Knickarmroboter

Co-Injektion (Barriere-/Sandwich-Spritzgießen)

Hybrid-Spritzgießen (Metall / Kunststoff)

Ressourcenmanagement

Produktion

Technical Excellence thanks  to Digital Assistance

After a year’s forced break of Fakuma, Wittmann Battenfeld is announcing the new servohydraulic SmartPlus machine as the highlight of this year’s trade show. It is claimed to be characterized by high economic and energy efficiency and repeat accuracy.

The new SmartPlus machine is equipped with the HiQ Flow software and the CMS Light condition monitoring system

Messe Fakuma

kunststoffe-international.com

Injection Molding Innovations In-House, Live and in Color

For a cutlery series made of a new biopolymer, three full hot runner molds with digital process monitoring were developed in close cooperation with mold maker Uniform and hot runner specialist Ewikon.

The 16-drop family mold on the machine. The removal and packaging of the parts are fully automated

16:9

Complete Digital Hot Runner Solution for Automated Biopolymer Processing

Condition Monitoring / Prozessüberwachung

Instandhaltung

Virtual Reality für die Qualitätssicherung

Heißkanalsysteme

Komponenten für die Kunststoffverarbeitung

Process Reliability Is Crucial

For the first time a readable digital watermark, imperceptible to the naked eye, has been incorporated into an injection-molded flip cap.

On the flip cap, the digital watermark is not visually perceptible, but can be read like a code by specialized high speed camera

Integration of Digital Watermarks in Complex Injection Molded Packaging Products

Bildverarbeitung

Fertigungsautomation

Barcode-Systeme

Identtechnik

Inspektion, Analyse und Sortierung von Rohmaterial

Key to Purity of Recycled Resins

The article demonstrates the use of digital twins for molds in injection molding through the integration of track-and-trace technologies for data collection.

An RFID reader records whether a mold is ready for the setup process

How Track-and-Trace Technologies Can Support Mold Management

RFID

RFID Teileidentifikation

Digitaler Zwilling

The Digital Mold Twin

Internal pressure loads are typical for fiber-reinforced plastic components. To increase the burst strength of components, the fiber orientation can be modified in a targeted way during injection molding by means of a rotating mold core. A newly developed simulation method allows this modified fiber orientation to be taken into account at the design stage.

Practical implementation of a mold system with rotating core.

Mold System with Rotating Core Improves Mechanical Properties

Werkstoffprüfung, mechanisch

Messtechnik

Werkstoffprüfung

Design Methodology for Parts Subject to Internal Pressure

Family molds belong to the state-of-the-art in injection molding – at least when wall thicknesses and volumes of individual components vary considerably. Using a trial mold soon ready for series production, Synventive demonstrates that – though demanding – optimal process control can be achieved using the right technology. The filling of each mold cavity is controlled individually and in real time. The Kunststoffe editorial team were among the first guests at the new Tech Center.

View into the mold space of the Engel Duo 2700 at the Tech Center. In the background, a 6-axis robot with 180 kg load-bearing capacity which removes the components.

Single-Shot Injection Molding of Heterogeneous Components

Schröder, Susanne

Leading-Edge Process Control

The plastics processor TKW Molding, which specializes in safety-related automotive components, is responding to the increasing requirements of its tier 1 and OEM customers by extensively automating its injection molding production. This also encompasses downstream process steps, such as integrated component testing, traceable part deposition and packaging. The company has been working closely with Arburg in this field since 2020.

A robotic system removes the parts from TKW’s 8+8-cavity mold.

Fully Automated In-Mold Assembly Process at TKW Molding

Optische Mess- und Prüftechnik

KFZ-Zulieferer

Dienstleistungen

Safely Belted in

Design Surfaces thanks to Innovative Mold Coating

New Injection Molding Technology for Foamed Parts with Class A Surfaces

With the MicroJect Advanced, Faurecia, a company of the Forvia Group, is presenting a new manufacturing process for foam injection molding.

With the MicroJect Advanced, Faurecia, a company of the Forvia Group, is presenting a new manufacturing process for foam injection molding. The motivations for the development were to achieve a sustainable manufacturing process as well as greater design freedom and product quality. By combining an innovative mold coating and modified process control, substantially more lightweight visible components with flawless surface quality can be manufactured with a significantly lower carbon footprint.

In foam injection molding, surface defects (so-called foam streaks or silver streaks) usually occur, which until now have made it impossible to use foamed components in visible applications. The new “MicroJect Advanced” manufacturing process produces flawless visible parts with intricate textures or other design surfaces (Fig. 1). In addition, the parts are significantly more lightweight but still stable thanks to their bionic design, which is inspired by nature. In the overall process, the carbon footprint can be reduced by half compared to conventional solutions. The process is presented at K 2022 at the booth of the machine manufacturer Engel with an example of various textured surfaces in a plate demonstrator and a door trim demonstrator using this technology (Title figure).

As a first step, an inert gas (CO2 or N2) is dissolved in the plastic melt under permanent back pressure. During injection into the cavity, there is a pressure drop resulting in foaming of the plastic melt comparable to suddenly taking the cap off a bottle of soda pop. In the injection mold, a so-called integral foam is produced: a molding with unfoamed skin and a foamed core.

Without an appropriate countermeasure, the part has a rough surface with foam streaks, which make it difficult or impossible to use the thermoplastic foam injection molding (TFIM) process for visible applications. Although solutions preventing, or at least minimizing, streaks – one of them is dynamic mold temperature control – have long been available, they have not been able to gain widespread acceptance on the market. Complex processes, higher equipment and material costs, longer cycle times and high energy costs made it difficult to implement them economically. In addition, the surface quality was insufficient.

The new technology allows foam injection molding to be used much more widely. The production of lightweight TFIM parts with a flawless Class A surface is made possible by an innovative mold coating (manufacturer: Eschmann Textures International GmbH). This is a thin layer of a technical ceramic that also carries the texture of the visible component.

During injection, the ceramic acts as a short-term heat barrier, which keeps the melt at the cavity wall in a plastic state just long enough for a sufficiently high cavity pressure to build up in order to smooth the surface. Because the mode of operation of the variotherm (dynamic) mold cooling is similar, though without supply of external energy, one can speak of a “passive variotherm process”. Despite the thermal insulation, the cycle time is not prolonged. Consequently, not only foam streaks can be completely prevented, but tiger stripes, differences in gloss, pressure marks or ghosting and even visible weld lines are now also a thing of the past.

The surface textures are introduced into the ceramic coating with the latest generation of an ultrashort pulse laser. Its pulse frequency is more than two orders of magnitude above that of normal commercial lasers, such as are used for texturing metal surfaces. Compared with steel surfaces, much more intricate and complex textures can be introduced in a ceramic coating. The method thus offers completely new design possibilities for the surfaces of plastic components (Fig. 2), which in the future will even be usable as high gloss decorative parts and will thereby make complicated and expensive painting, or even laminating, unnecessary.

TFIM integral foam components are comparable to sandwich structures in terms of the material mechanical properties. This is due to their outstanding weight-specific flexural and torsional properties, predominantly in aircraft, ships and boats, as well as wind turbines. Moreover, the cross-section of an integral foam, unfoamed on the outside and cellular on the inside, corresponds to the structure of a human bone. This three-dimensional material configuration proves especially useful in lightweight engineering, and is not the only inspiration from nature.

Bionics – Lightweight Engineering Inspired by Nature

Self-developed CAE simulation routines can predict both the mechanical properties of integral foam components (structural simulation), as well as the flow behavior (structural simulation) of gas-loaded melts. Part regions with inadequate mechanical properties are stiffened with reinforcing ribs, which are disposed as honeycombs in a normal case. Slim geometries with ribs can be made just as stiff as the thick solid material without ribs, even with a lower material input. Very similar to a water-lily plant, on which an infant can sit without sinking, future TFIM components from Faurecia will consist of a thin skin with a sophisticated stiffening network at the back.

To avoid the risk of sink marks, ribs or B-side features (screw or weld bosses, clips or retainers) can generally be connected on the reverse of the component at right angles. This is particularly unfavorable for the force transmission because, due to the right-angled arrangement at the rib-base, there is increased stress here, which can lead to failure of the rib (notch effect). To minimize the notch effect, another example from nature was used. At this point, technology copies the architecture of a tree. Its trunk follows a geometrical principle that significantly reduces the notch effect. All the B-side features thus become more robust and can transmit larger forces. Such a functional part design cannot be applied in conventional injection molding. This is only possible due to the significantly greater design freedom in Microject Advanced.

The dissolved blowing agent improves the flowability of the melt significantly (plasticizing effect) and the non-localized foam pressure in addition permits significantly thicker ribs without sink marks. Both have the consequence that visible components can be made significantly thinner than before. In most cases a material saving of between 10 and 20 % is possible by altering the design to take account of foam. The foaming process itself permits a further weight saving of 5 to 7 % even for thin-walled components.

Besides a demonstrator with various textured surfaces that is produced at K 2022 by physical foaming (MuCell process), Faurecia also will show a demonstrator door trim part which is 23 % lighter than its unfoamed counterpart (Fig. 3). Of this saving, 17 % is accounted for by the above-described design change and 6 % by the foaming itself. Due to the significantly lower cavity pressure, the components can be realized with only 10,000 kN clamping force, while at least 18,000 kN is required for the unfoamed version.

Compared to unfoamed injection molding, significantly less energy is necessary for the foamed door trim. The reason for this is the lower required clamping force as well as the per se lower material consumption. A life cycle assessment (LCA) of the global warming potential (GWP) performed by Faurecia has shown that the carbon footprint of the production process is halved. The CO2 emitted by obtaining and manufacturing the raw materials used is reduced by 23 %.

To make the product even more sustainable, the components are injected with a newly developed polypropylene type with a high recyclate content. The compound was developed especially for the new technology by experts of the Faurecia Sustainable Material Division (SMD). Besides good foamability, the material development also focused on matt, scratch-resistant surfaces. For the developers, it was important for the surfaces to have a soft, tactile feel, which, for textile surfaces, gives the component surface a pleasant appeal, even for different textures. If the innovative textures are combined with tailored color additives in the polymer, the grain character can be additionally emphasized and the visual experience made even more authentic. The validation of the new technology was successfully concluded some months ago.

Faurecia Innenraum Systeme GmbH  

Ausgabenartikel

Single-source component: the door panel comes directly from the injection-molding machine as a ready-to-install visible component with different grains.

Fig. 1. TFIM component from traditional manufacturing (right) and MicroJect Advanced demonstrator with graining (left). 

Fig. 2. Examples of textures (clockwise from top left): textile, slate and cork, textiles in various colors, wood.

Fig 3. The door trim, which is about 25 % more lightweight than an unfoamed part, with a stable internal structure, is shown at the Engel booth.

Name - Hauptartikel

 Jochen Klos is R&D Manager Injection Moulding at Faurecia Interiors in Hagenbach, Germany.

Dr. Alexander Roch is R&D Team Leader Injection Moulding, Technical Lead Microject Advanced at Faurecia Interiors.

Company contact: <a href="https://www.faurecia.de/en" target="_blank">www.faurecia.de</a>

A broad styling variety for injection molded parts: with Cera-Shibo, Eschmann Textures offers a coating process that allows different designs to be produced from the same mold. In conventional processing methods, the structure is determined by the mold. Cera-Shibo is different: with a heat-resistant, wear-resistant ceramic coating on the mold surface, plastic parts with a virtually unlimited bandwidth of individual surface structures can be produced – with Cera-Shibo, the structural information lies in the ceramic layer. This layer can be removed completely from the mold at any time and reapplied without additional polishing work, wall thickness changes or the like.

<a href="https://eschmanntextures.de/?lang=en" target="_blank">eschmanntextures.de</a>