A 360-degree look at resin conveying systems: types, operation, economics, design, installation, components and controls.
This Knowledge Center provides an overview of resin moisture and the drying process, including information on the best drying practices for your manufacturing facility. Injection Blow Moulding Machine Price
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Combat the skilled labor shortage using this comprehensive resource to train your own plastics processing experts.
Deep dive into the basics of blending versus dosing, controls, maintenance, process integration and more.
This Knowledge Center provides an overview of the considerations needed to understand the purchase, operation, and maintenance of a process cooling system.
Learn about sustainable scrap reprocessing—this resource offers a deep dive into everything from granulator types and options, to service tips, videos and technical articles.
Second quarter started with price hikes in PE and the four volume engineering resins, but relatively stable pricing was largely expected by the quarter’s end.
While the major correction in PP prices was finally underway, generally stable pricing was anticipated for the other four commodity resins.
Despite price increase nominations going into second quarter, it appeared there was potential for generally flat pricing with the exception of a major downward correction for PP.
First quarter was ending up with upward pricing, primarily due to higher feedstock costs and not supply/demand fundamentals.
Despite earlier anticipated rollover in prices for most of the volume commodity resins, prices were generally on the way up for all going into the third month of first quarter.
While price initiatives for PE and PVC were underway, resin prices had rollover potential for first two months of 2024, perhaps with the exception of PET.
Resin drying is a crucial, but often-misunderstood area. This collection includes details on why and what you need to dry, how to specify a dryer, and best practices.
Take a deep dive into all of the various aspects of part quoting to ensure you’ve got all the bases—as in costs—covered before preparing your customer’s quote for services.
In this collection of articles, two of the industry’s foremost authorities on screw design — Jim Frankand and Mark Spalding — offer their sage advice on screw design...what works, what doesn’t, and what to look for when things start going wrong.
In this collection, which is part one of a series representing some of John’s finest work, we present you with five articles that we think you will refer to time and again as you look to solve problems, cut cycle times and improve the quality of the parts you mold.
Gifted with extraordinary technical know how and an authoritative yet plain English writing style, in this collection of articles Fattori offers his insights on a variety of molding-related topics that are bound to make your days on the production floor go a little bit better.
In this three-part collection, veteran molder and moldmaker Jim Fattori brings to bear his 40+ years of on-the-job experience and provides molders his “from the trenches” perspective on on the why, where and how of venting injection molds. Take the trial-and-error out of the molding venting process.
Mike Sepe has authored more than 25 ANTEC papers and more than 250 articles illustrating the importance of this interdisciplanary approach. In this collection, we present some of his best work during the years he has been contributing for Plastics Technology Magazine.
In this collection of content, we provide expert advice on welding from some of the leading authorities in the field, with tips on such matters as controls, as well as insights on how to solve common problems in welding.
Mold maintenance is critical, and with this collection of content we’ve bundled some of the very best advice we’ve published on repairing, maintaining, evaluating and even hanging molds on injection molding machines.
Thousands of people visit our Supplier Guide every day to source equipment and materials. Get in front of them with a free company profile.
NPE2024: Lowering barriers to additive manufacturing adoption in toolmaking.
Allegheny Performance Plastics turned to 1factory's cloud-based manufacturing quality control software for streamlined, paperless quality systems.
To design the best mixers for single screws, you must completely understand how polymer moves through a mixer channel or groove.
NPE2024: Focus is on additives for plastics including PVC and WPC industries.
At NPE2024, Novatec moves to rewrite the rules for material conveying with patent-pending smart-pump technology.
While the major correction in PP prices was finally underway, generally stable pricing was anticipated for the other four commodity resins.
With no minimum order and an impeccable record of on-time delivery, Precision Color Compounds is becoming a force in the color masterbatch business.
Thermosets were the prevalent material in the early history of plastics, but were soon overtaken by thermoplastics in injection molding applications.
After a six-year hiatus, this year’s show was a resounding success, with meaningful technologies on display that will help processors run their businesses more efficiently.
Key factors for the progress are innovative materials, advanced automation and precision engineering.
Topping five other entries in voting by fellow molders, the Ultradent team talks about their Hot Shots sweep.
Serendipitous Learning Opportunities at PTXPO Underscore the Value of Being Present.
Introduced by Zeiger and Spark Industries at the PTXPO, the nozzle is designed for maximum heat transfer and uniformity with a continuous taper for self cleaning.
Ultradent's entry of its Umbrella cheek retractor took home the awards for Technical Sophistication and Achievement in Economics and Efficiency at PTXPO.
technotrans says climate protection, energy efficiency and customization will be key discussion topics at PTXPO as it displays its protemp flow 6 ultrasonic eco and the teco cs 90t 9.1 TCUs.
Shibaura discusses the upcoming Plastics Technology Expo (PTXPO) March 28-30
Line features a single touchscreen for easy setup and operation.
Oerlikon HRSflow’s T-Flow HRS control has launched with three models that are configurable to multiples of six zones.
NPE2024: Dukane’s new Ultrasonic Thin Wall welding system is well suited for welding applications of PP to PP TD25 painted parts.
Series offers higher output, lower melt temperatures and energy savings.
Noting that geopolitical changes require new corporate strategies, European plastics and rubber machinery trade groups announced that incoming orders fell 22% in 2023.
System tracks, controls and saves everything from material recipes to process parameters, operator activity from logging on to start, to emergency stops and more.
Mixed in among thought leaders from leading suppliers to injection molders and mold makers at the 2023 Molding and MoldMaking conferences will be molders and toolmakers themselves.
After successfully introducing a combined conference for moldmakers and injection molders in 2022, Plastics Technology and MoldMaking Technology are once again joining forces for a tooling/molding two-for-one.
Multiple speakers at Molding 2023 will address the ways simulation can impact material substitution decisions, process profitability and simplification of mold design.
When, how, what and why to automate — leading robotics suppliers and forward-thinking moldmakers will share their insights on automating manufacturing at collocated event.
As self-imposed and government-issued sustainability mandates approach, injection molders reimagine their operations.
August 29-30 in Minneapolis all things injection molding and moldmaking will be happening at the Hyatt Regency — check out who’s speaking on what topics today.
Get your clicking finger in shape and sign up for all that we have in store for you in 2023.
Molding 2023 to take place Aug. 29-30 in Minnesota; Extrusion 2023 slated for Oct. 10-12 in Indiana.
Join this webinar to learn about Conair's patented Conveying with Optimizer system, which utilizes artificial intelligence (AI) to overcome resin conveying issues automatically. Conveying with Optimizer uses valves, remote sensors and AI to eliminate conveying challenges that operators face daily throughout the plant. With this new fully-retrofittable solution, interruptions like clogged filters, air leaks, changes in density or distance, moisture changes, and operators making manual adjustments can all be eliminated with Conair's Conveying with Optimizer. Agenda: What exactly is Conveying with Optimizer? What are the benefits of using Conveying with Optimizer? What problems does Conveying with Optimizer overcome? How to upgrade your system
Cooling time is typically the longest step of the molding process. How can you make it more productive? Learn how cooling time can be turned into production time by running two molding processes simultaneously on a single molding machine. For longer cycles, this can mean twice the productivity. In this webinar, you'll learn more about the Shuttle Mold System and how to calculate its potential productivity impacts for your application. Agenda: Learn how the Shuttle Mold System can deliver value to your business See the recent technical updates made to the system Calculate the potential impact on productivity
Discover possible applications in large format printing including layup tools, transport modules, film fixation devices, design components and enclosures. These are used in various industries such as automotive, aerospace, architecture and many others. Agenda: Possible applications in large format printing: layup tools, transport modules, film fixing devices, design components and enclosures. Process reliability and component quality in component production Pros and cons of the technology Sneak peek into current development projects—What will the large format printing of tomorrow look like?
In this webinar, Cold Jet will discuss some of the ways processors use dry ice such as in-machine mold cleaning at operating temperatures, de-flashing or de-burring parts, improving OEE scores, extending mold life, cleaning parts before painting, post-processing 3D printed parts, lowering GHG emissions, and monitoring and reporting the process. Agenda: Cold Jet Overview & Dry Ice 101 Understanding the Process and Fine-Tuning Techniques Case Studies: Applications in Plastics Monitoring the Process Exploring the Importance of Dry Ice Cleaning in an ESG Era
Finding it hard to get technical talent? Experiencing the pain of a knowledgeable, long-term employee's retirement? Learn how plastics processors are training generative AIs on their operations and unlocking the value from their tribal knowledge. Plastics processors are training generative AI models on their operations — from machine manuals to tools, polymers, procedures, maintenance records and engineering projects. Applying generative AI in the right ways can lower plastics processors' costs, improve overall equipment effectiveness (OEE) and upskill teams. In this webinar, you'll learn how to deploy AI technical assistants to your teams, what works and what doesn't, and how to use AI to build an organization that never loses tribal knowledge and fosters inter-team collaboration. Agenda: What is generative AI and how can its cognitive abilities be applied to plastics? Case study: how an injection molder trained a large language model on manuals and maintenance records to reduce downtime Case study: using generative AI in engineering teams to improve product development Live demonstration of a generative AI deep-trained on plastics knowledge Looking to the future: five predictions for an AI-augmented workforce in plastics
Turnaround time can be as low as 24 hours, although two or three days might be more typical. Rapid prototyping like this is especially useful to quickly identify critical end-use part geometries that will work in the molding process. Key components include material choice, 3D printing technology selected, use of adaptable mold bases for the mold inserts and implementation of appropriate injection molding process conditions. This presentation will review work conducted toward the assessment of a high-stiffness, high-temperature-resistant ceramic modified urethane acrylate for injection molding inserts. Agenda: Guide for 3D-printed injection mold inserts Optimization of digital light processing (DLP) printing Compatibility with various thermoplastics Real-world application success stories
Debuting in 2010, the Parts Cleaning Conference is the leading and most trusted manufacturing and industrial parts cleaning forum focused solely on delivering quality technical information in the specialized field of machined parts cleansing. Providing guidance and training to understand the recognized sets of standards for industrial cleaning, every year the Conference showcases industry experts who present educational sessions on the latest and most pressing topics affecting manufacturing facilities today. Discover all that the 2022 Parts Cleaning Conference has to offer!
Presented by Additive Manufacturing Media, Plastics Technology and MoldMaking Technology, the 3D Printing Workshop at IMTS 2024 is a chance for job shops to learn the emerging possibilities for part production via 3D printing and additive manufacturing. First introduced at IMTS 2014, this workshop has helped hundreds of manufacturing professionals expand their additive capabilities.
Formnext Chicago is an industrial additive manufacturing expo taking place April 8-10, 2025 at McCormick Place in Chicago, Illinois. Formnext Chicago is the second in a series of Formnext events in the U.S. being produced by Mesago Messe Frankfurt, AMT – The Association For Manufacturing Technology, and Gardner Business Media (our publisher).
Learn here how to take advantage of new lightweighting and recycle utilization opportunities in consumer packaging, thanks to a collaboration of leaders in microcellular foaming and multilayer head design.
FIG 1 Retrofit of Trexel’s B-Series gas-metering equipment to add blowing agent to the polymer melt through a port in the extruder barrel. (Images: Trexel Inc.)
Use of recycled plastics materials is a critical factor in the move toward a fully closed-loop economy in the plastic industry. Simply put, producers must reduce their energy and raw-material consumption to meet strict new legislation touted for introduction in 2025, as laid out in the proposed packaging regulation published in November 2022 by the European Commission. Cosmetic products that are contact-sensitive, for example, will contain 40% postconsumer regrind (PCR) and all other bottle packaging will contain 35% and 65% by 2030 and 2065, respectively. This is a tall order.
The challenge is not only the supply, availability and quality of recycled resins but also the development of new processes to enable their use and exploit their potential. With the sudden requirement for PCR and the need for respectable quality, cost will likely be an issue. Brand owners, in particular, are looking for ways to remain cost-competitive with the virgin product configurations of today’s common packaging specifications. Lightweighting through foaming has also gained growing attention and process adoption in recent years as an alternative to downgauging, which may compromise topload performance.
Trexel, a market leader in foaming technologies for lightweighting, and W. Müller, a market leader in blow molding multilayer head design, have partnered to create a lightweighting solution for inclusion of PCR and lowering the cost of bottle production without significantly sacrificing mechanical properties. Trexel has been delivering both physical and chemical foam lightweighting solutions for injection and blow molding. Its MuCell physical foaming technology is now standard or optional on many OEM injection molding platforms. With a recent focus on packaging solutions in injection molding, plus the company’s history of foaming blow-molded automotive ducts with the accumulator-head process, Trexel has implemented a MuCell foaming solution for extrusion blow molding (EBM) on shuttle and wheel machinery. Trexel is now working with brand owners on scale-up bottle projects.
FIG 2 Left: Solid, natural color. Middle: Foamed with no TiO2. Right: Foamed with 2 wt% TiO2 in outside skin. Foaming adds opacity with less or no need for pigment.
The multilayer solution involves metering nitrogen into the barrel of the EBM machine and foaming the core layer of a three-layer sandwich such that the layer ratio (by thickness) remains similar to the solid predecessor three-layer design but with reduced weight in the PCR core. There is also reduced core extruder speed associated with a given volumetric bottle output. By specifically coupling the MuCell process with a proprietary patented additive, impact strength, topload and ESCR will pass the necessary industry tests. Typically, there has been an improvement of up to 3 times in impact performance over previous foaming technologies, which is driving the ability to make larger foam-core bottles. The system and method are license-free and may be retrofitted to the existing screw and barrel, as depicted in Fig. 1. In addition to weight savings, TiO2 and other white masterbatches can often be reduced or eliminated, because foam adds an opaque appearance, as shown in Fig. 2.
Lightweighting through foaming is an alternative to downgauging, which may compromise topload performance.
W. Müller’s multilayer head and extruder systems can be retrofitted to most monolayer systems as well as on a new system. W. Müller, which built its first three-layer head in 1990, brings significant process experience with PCR-laden products through its RECO head series. MuCell is a physical foaming process, depending partially on the pressure events in the head or multiple heads in structure of three or more layers. As noted by Jens Schlueter, president of W. Müller USA, “Although there are many standard three-layer extrusion head designs out in the market, it is essential to have the experience with how to create designs that accommodate the foaming process. Understanding melt flow, melt pressure and how to perfectly dimension the flow channels inside the head is critical to a successful foaming application. Our expertise in providing custom-designed heads for different materials and designs ensures that our customers get the right solution for their needs and particular specifications.”
Of particular importance to the process is the ability of the Trexel SCF (supercritical fluid) delivery system to respond to pressure fluctuation that may arise from the addition of some lower-grade PCR to the extruder. Trexel’s proprietary system will “learn” process patterns and react to real-time events to keep foaming levels consistent to ensure process stability and consistent bottle geometry. To enable this, simple process timing signals from the blow molding machine are used.
W. Müller has installed two lab foaming systems, one at its headquarters in Troisdorf, Germany, and the second at its U.S. office in Agawam, Mass. They are both equipped with Trexel’s latest B120 SCF delivery system and handled bottle mold for use in demonstrations. Clients may also pick from other standard molds or supply their own molds to test out the technology.
Of particular importance is the ability of the gas-injection system to respond to pressure fluctuation that may arise from addition of some lower-grade PCR to the extruder.
To retrofit the pumping system, a hole is drilled in the existing barrel in a position so there is enough residence time to dissolve nitrogen gas in the melt. Trexel has conducted background research to mathematically define the exact parameters required to ensure homogeneous gas diffusion in such processes through work with its recently patented injection molding screw designs. Because almost 10 times less gas is used in the foam blow molding process than in injection molding, there is usually enough residence time to mix gas with the existing blow molding screw design, and therefore the process will not typically require a new screw and barrel.
It is anticipated that in the future Trexel’s SCF delivery system controls will be integrated into the W. Müller control system to provide a one-stop foaming add-on which will convert an existing monolayer system to a full multilayer foam system.
FIG 3 Case study bottle mold for topload and drop-impact testing.
The following case study was used to corroborate and summarize recent work using the demonstration mold. A blow molding system was configured as in Fig. 2 and combined with Trexel’s handled bottle mold as shown in Fig. 3. The die tooling was downsized such that the parison layflat dimension was the same for solid and foamed extrudate – yielding the same amount of flash/top/tail. In some cases, die ovalization may change slightly from that for a solid product.
FIG 4 Parison layer structures between solid and foam test bottles. Die tooling was downsized so that the parison layflat dimension was the same for solid and foamed extrudate – producing the same amount of flash/top/tail.
Weight was then reduced in the core extruder, as shown in the center bar in Fig. 4; here the tail was too short to actually mold a product. Gas was then injected and the structure was foamed back to a thickness similar to a solid part, as shown on the right-hand bar of Figure 4. Given that stiffness is a key factor that varies as a cube function of nominal thickness, overall thickness can be manipulated to offset the reduction in density, which varies only linearly with stiffness. In essence, foam has a better stiffness-to-weight ratio than solid structures.
Blow pressure was then applied, typically lower than for solid molding, sometimes in multiple stages. The lower pressure at these thicknesses does not introduce the need for greater cooling time or a change in mold venting. In the process, minor calibration or crushing of the structure takes place to leave the final product as shown in Fig. 5. For example, the final foam parison from Fig. 4 is 2.16 mm, which is calibrated (compressed) by nearly 50% during the blow process to leave a final thickness of 1.12 mm, shown in Fig. 5.
FIG 5 Final bottle structures after blowing and foam versus solid metrics (table), showing savings in bottle weight, cost and cycle time.
The result was a foamed bottle that is 6 g lighter, with an overall density of 0.830 g/cc and a core density of 0.760 g/cc. Nominal thickness of the outside layer was the same as in the solid structure, and extra thickness to maintain stiffness came from the foamed layer. The cycle time in this instance was reduced by 2.5 sec. The final metrics of the bottle are shown in the table in Fig. 5, which notes savings in bottle weight, cost and cycle time. It should be noted there are multiple ways to quantify the savings. Cycle time may remain constant (same volumetric output) but with reduced material consumption; or alternatively there might be similar material (weight) throughput as with a solid wall, but with increased volume output — more bottles per hour. In this case study, it was a mixture of both.
FIG 6 Scanning electron micrograph of a typical three-layer foam structure, with a 1.3 mm total thickness, outer solid skin layer of 0.17 mm, foam layer of 0.92 mm and inner solid skin layer of 0.21 mm.
An important factor in the technology, as noted, is the homogeneous mixing of gas, but also the synergy of the gas desorption at the instant that pressure is released at the die exit. This creates very small bubbles with an aspect ratio typically no more than 2:1 and cell size less than 100 microns after blowing (Fig. 6). The foam parison continues expanding such that there is ample thickness in the base of the bottle. Unlike traditional nucleating agents, the proprietary nucleant additive in this process does not negatively affect impact strength (if, for example, you were to put it in an unfoamed product). The combination of those factors enables the foam technology to apply to much larger bottles than just 200 ml and pass impact tests.
Three base tests were performed on the test bottle. The drop-impact test was 11.5 ft for the foamed bottle with an ESCR test pass. Topload test results showed that for the same weight (comparing Trials 8 and 11 in Fig. 7), force per mm of thickness was the same for foamed and unfoamed bottles. Furthermore, the foamed bottle showed a 20% increase in total energy absorbed before the peak topload was reached.
FIG 7 Topload tests show that for foamed and unfoamed bottles of the same weight (trials 8 & 11), topload force per mm of thickness was the same, but the foamed bottle exhibited 20% more total energy absorbed before peak topload was reached. A solid bottle of the same thickness but higher weight showed greater topload strength.
Further work is now being conducted on different materials and shapes for brand owners. This extends to biopolymers, which will not be subjected to the regulations in Europe when they begin to roll out but would benefit from cost reduction. Work is also being conducted on wheel machines where the technology has been run successfully at full scale on larger bottles for applications like household detergents.
Trexel has shown a new and improved way to foam bottles with the ability to reduce the cost of PCR-laden bottles and/or simply to lightweight bottles as an alternative to downgauging which is limited by topload strength. Foam has an improved stiffness-to-weight ratio and provides opacity without adding masterbatch.
Ability to pass topload and drop-impact tests enables foaming to be used in much larger bottles.
Trexel has addressed a key shortcoming of previous renditions of the foaming technology — in particular, drop-impact resistance has been addressed, while topload strength can be maintained by increasing thickness at the foamed lower density. Foaming will not be suitable for every product, such as monolayer, very thin, heavily embossed or with ultrahigh drop-impact requirements. But the list of successful applications is ever growing and gaining attention.
Foaming can be retrofitted to old machines or installed as new. In the former instance, W. Müller and Trexel have partnered to provide the ability to change a monolayer machine to make multilayer foam structures with minimal capital investment and no royalties.
ABOUT THE AUTHOR Sam Dix is the R&D director at Trexel and previously of Zotefoams PLC. He has dedicated over 20 years to developing innovative lightweighting solutions for the plastics industry. This has included a wide range of hardware, systems and processes for customers worldwide. Contact: S.Dix@trexel.com; 781-266-7391; trexel.com.
Reinvention is essential at Capital Polymers, a toll recycler that has completely transformed its operation in a short period of time.
Compatibilizers are proving their worth in boosting critical properties such as impact/stiffness balance of PCR and PIR blends of polyolefins and other plastics.
St. Joseph Plastics grew from a simple grinding operation and now pursues growing markets in recycled PP, food-grade recycled materials, and customized post-industrial and post-consumer compounds.
PureCycle prepares to scale up its novel solvent recycling approach as new facility nears completion.
At K 2022 this month, W. Müller is presenting a system for PCR processing in a three-layer coextrusion, using an energy-saving barrel-heating system.
Agreement with MuCell Extrusion allows Trexel to pursue foam blow molding in packaging as well as automotive.
MuCell technology gains new momentum in blow molded packaging through this partnership of a leader in physical foaming with supercritical gases and a leader in coex blow molding hardware and controls.
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