Audi Plans To Reduce Prototyping Times

The use of 3D printers has exponentially expedited the prototype process by increasing speed and production time. Audi plans to reduce prototyping times by up to 50 percent by using entirely transparent, multi-colored tail light covers in a single print. This eliminates the need for the previous multi-step process that Audi was using prior.

German automotive giant Audi AG has adopted full color Stratasys 3D printers, which it will use to prototype taillight covers.

Source: http://www.plasticsnews.com/article/20180608/NEWS/306089999/audi-to-significantly-reduce-prototyping-times-with-stratasys-3d

Spotlight: Injection Mold Machines

At NPE 2018, there were many huge injection molding machines that fans were able to visit in person. Big-scale machines, such as the one Milacron Holdings LLC that won the press prize or Arctic Cat’s Wildcat XX, are just two of the items being displayed. Learn more about the injection mold machines that were showcased at NPE below.

 

Fans of large-tonnage injection molding machines will be able to partake of the big iron at NPE2018.

Milacron Holdings LLC takes the big-press prize: a giant two-platen machine with 2,250 tons of clamping force. Big-press history fans take note: Milacron says it’s the biggest injection molding press ever to operate at an NPE.

You can see it at Booth W2703, molding a dashboard for Arctic Cat’s new Wildcat XX, a juiced-up, two-passenger utility vehicle with an off-road-racing suspension. The dash panel weighs 10.5 pounds.

Milacron has sold the 2,250-tonner to Innovative Injection Technologies Inc., a West Des Moines, Iowa-based custom injection molder known as i2Tech.

The molder does lot of work for utility vehicle makers Arctic Cat — which was purchased a year ago by Textron Inc. — and Kawasaki Motors Corp. Another major customer is agricultural ​ equipment maker Deere & Co.

“It’s going to additional automotive and recreational vehicle work,” said i2Tech President Josh Janeczko.

He said high-end utility vehicle sector is strong. “We’re seeing continued increases in sales. It doesn’t seem to lay up, and they continue to invest new capital for new programs,” Janeczko said.

The 2,250-ton Milacron machine will i2Tech’s eighth injection press of more than 1,000 tons, he said.

Janeczko said that after NPE, the big Milacron press will go back to Milacron’s main plant in Batavia, Ohio, for additional testing before getting delivered to West Des Moines in August.

The press, called the Cincinnati after Milacron’s home town, is a new large-tonnage two platen machine with a shorter footprint and high performance.

i2Tech is a longtime Milacron customer. In 1968, the forerunner of i2Tech, Mid-Central Plastics Inc., bought one of the first three injection molding machines made by Cincinnati Milling Machine Co. For more than four decades, the press molded parts; for many years, it turned out seed discs. Finally, in 2011, i2Tech decommissioned the press and replaced it with a new Milacron Roboshot all-electric machine. Milacron took the 1968 machine back to Batavia, cleaned it up and placed it on display in its factory.

Janeczko plans to attend NPE2018. “This is certainly an emotional purchase with me. We have a long history with Milacron. And so, when they came to me with this opportunity, I jumped all over it,” he said.

Here are some of the other big-machines that will make news at NPE2018:

In a North American first, Engel Holding GmbH will run a 1,000-metric-ton press and a fully automated production cell running the DecoJect process, combining injection molding and in-mold graining.

During NPE, an Engel Duo press will make interior upper door trim with various surface textures, such as refined leather grain or a modern carbon look.

Engel will be at Booth W3303.

KraussMaffei Group will show its two-platen GX series press with 900 metric tons of clamping force.

At NPE, the GX will produce 20-liter buckets in a two-cavity mold, doing in-mold labeling.

KraussMaffei will be in Booth W403.

Wittmann Battenfeld Inc. will bring a MacroPower press with 850 metric tons molding a spoiler on a single-cavity mold. The work cell will do condition monitoring for preventive and predictive maintenance.

Wittmann Battenfeld will be at Booth W3742.

Wilmington Machinery Inc., in Booth W1823, will discuss an 800-ton version of its Lumina MP800 medium-pressure injection molding machine.

Wilmington said the Lumina is now available with a new compounding option, for extruding custom-formulated materials, then inject them directly into the part.

Arburg GmbH & Co. used be known as a small-tonnage injection press maker. That ended a dozen years ago, when the company cracked the 550-ton mark, officially in the “mid-sized” category.

Now NPE2018 marks the U.S. trade show introduction of a 730-ton hybrid Allrounder 1120 H in Booth W1325.

The 730-ton press meets a demand of U.S. customers for Arburg to produce larger-tonnage machines, company officials said.

SOURCE: http://www.plasticsnews.com/article/20180403/NEWS/180409981/big-injection-molding-machines-in-the-spotlight-at-npe2018

Thermoformed compostable CPLA food trays to be produced during NPE2018

If molds could only be made for one thing, making them for food might be the best option. These new food trays would be able to withstand temperatures of 250 degrees, and you can toss them right in the dishwasher. That is a pretty versatile food tray, that can handle almost anything you can give it.

CPLA food trayOMG SRL (Turin, Italy) will be exhibiting the all-inclusive servo-driven Thermoformer at NPE2018 in Booth #S34034. During exhibiting hours the company will be thermoforming 100% compostable crystallized CPLA food trays using materials supplied by Advanced Extrusion Inc. (Rogers, MN) that withstand a surface temperature up to 250°F and are microwavable and dishwasher friendly. The CPLA extruded sheet is made of plant-based resin, polylactic acid (PLA).

The energy-efficient electric OMG thermoformer produces finished parts by way of precision rule-die trimming on a heavy-duty tonnage 4-post, servo-driven trim press. It also offers these features:

Parts such as food trays, lids, containers, cups, and clamshells are loaded into an auto–stacking-counting station, an integral part of the OMG thermoforming system. Parts are then mechanically discharged onto a final packing station.

To further demonstrate the versatility of their machinery and engineered tooling, OMG will also thermoform AEI’s CPET withstanding temperatures of minus 20°F up to 375°F intended for conventional ovens. This will be done by using the same single-stage tooling used for the CPLA tray. Both materials incorporate a unique nucleating agent to promote accelerated crystallization during the thermoforming process.

AEI will be exhibiting at NPE2018 in Booth #S23014.

EastPack 2018 held June 12-14 in New York City features the latest in manufacturing and automation, a dedicated 3D Printing Zone, hundreds of exhibitors and a jam-packed 3-day packaging conference. For more information, visit the EastPack website.

Source: https://www.plasticstoday.com/packaging/thermoformed-compostable-cpla-food-trays-be-produced-during-npe2018/162381362058533

World’s first 3D-printed yacht features carbon-fiber-reinforced thermoplastic compounds

It seems as if just yesterday 3-D printing was becoming a novelty people were exploring. Now today, we have the world’s first 3-D printed yacht, and the carbon-fiber reinforced thermoplastic compounds holding it together just makes it all that more spectacular. The Lehvoss Group partnered with an Italian boat builder to knock this one out of the park.

The Lehvoss Group and its parent company Lehmann&Voss&Co of Hamburg, Germany, are partnering with Italian boat builder, Livrea Yacht, to build the world’s first 3D-printed sailboat. Since work began on the design in 2014, the group has supported process development and engineered its Luvucom 3F customized 3D-printing carbon-fiber-reinforced thermoplastic compounds specifically for the application.

The 3D-printed yacht features carbon-fiber-reinforced PEEK construction.

The innovative yacht, called the Mini 650, is the ambitious project of two Italian boat builders, Francesco Belvisi and Daniele Cevola. They are building it for the 2019 solo transatlantic yacht race, called the Mini-Transat, which starts in France and ends in Brazil. Livrea Yacht performs all simulation and evaluation work for the project, which is supported by engineers experienced in the America’s Cup and Volvo Ocean Race.

Concurrent with their work of designing and building the Mini 650, Belvisi and Cevola have driven the development of a dedicated direct extrusion 3D-printing technology with their company, Ocore, which is providing the required quality of parts for the yacht. Besides improving the printing hardware—robot, extruder and nozzle—they have patented a new material deposition strategy using an algorithm inspired by fractals.

The customized 3D printing materials engineered and supplied by the group are based on high-performance thermoplastic polymers, such as polyetheretherketone (PEEK). “To achieve the required mechanical properties, these polymers are reinforced with carbon fibers,” says Thiago Medeiros Araujo, Luvucom 3F Market Development Manager for the group. “In addition, they are modified to yield an improved layer strength with no warping of the printed parts. This results in parts that are stronger, lighter and more durable.”

According to Belvisi, Chief Technology Officer of Ocore, “The yacht will be highly competitive thanks to the light and strong 3D-printed parts. 3D printing dramatically reduces the build time for the yacht and also makes it more economical. We are looking forward not only to building the first 3D printed boat but also to winning the competition in 2019.” 

Commenting on the partnership with Lehvoss Group, Cevola, who is Managing Director of Ocore said, “We are excited to have them on board for this innovative project. Lehvoss Group is a widely recognized global manufacturer of customized polymer materials. Their sponsorship, additional support and experience with dedicated materials for our technology has helped a lot in driving our project. In addition, we now can also translate this technology to other industrial sectors for other applications.”

Lehvoss Group believes strongly in 3D printing as a way of producing higher performing and competitive parts. “We are happy to be a partner in this challenging and very exciting project,” said Medeiros Araujo. “The Livrea yacht will show what today’s dedicated processing and 3D printing polymers can already achieve.”

Source: https://www.plasticstoday.com/3d-printing/world-s-first-3d-printed-yacht-features-carbon-fiber-reinforced-thermoplastic-compounds/42309566458427

Recycling Plastic

Environmentalists across the globe are always looking for ways to reduse, reuse, and recycle. You can probably guess what one material is that is at the center of this. Plastic. Recycling plastic should always be second nature for people, but what if that went one step further by then using it as an energy source? Learn about this idea in the article below.

The plastics community continues moving forward to recovering currently noHefty Energy Bag home collectionn-recyclable packaging and other items and extracting energy from those materials. One of the most recent steps taken stateside was when Dow Packaging & Specialty Plastics (Midland, MI) and Keep America Beautiful announced in early January that two $50,000 grants were designated  for organizations in Cobb County, GA and Boise, ID, to establish the Hefty EnergyBag program in their respective communities.

The program offers an innovative approach to diverting plastics that cannot be recycled—such as chip bags and juice pouches—from landfills and converting the materials into valuable energy resources. The two winning communities will provide collected materials to facilities utilizing advanced non-combustion conversion technologies, which can generate a liquid fuel, such as diesel. To date, Hefty EnergyBag curbside and non-curbside programs, which include a 2014 EnergyBag Pilot in Citrus Heights, CA and permanent program in Omaha, NE, have kept 17.3 tons of plastics out of landfills.

PlasticsToday wanted to find out more about the program and where things are heading. Answering our questions is Jeff Wooster, Global Sustainability Director, Dow Packaging & Specialty Plastics.

What will come from the total $100k investment, how long will that last and what happens after the funding is exhausted?

Wooster: The winning communities are committed to continuing the program even after the initial one-time grant funding has been exhausted. The individual programs will determine how and when they spend the funds; the implementation phase is expected to occur in the first half of 2018 for Boise and in late 2018 for Cobb County.

As part of the investment, Dow will provide a framework for implementing the program and will facilitate the planning, implementation and measurement phases. Recipients are responsible for managing the program and soliciting involvement from key community stakeholders.

DowDupont's Jeff Wooster

The press release indicates that the materials will be sent to “facilities utilizing advanced non-combustion conversion technologies.” What more can you tell us about those operations?

Wooster: Materials collected through the Boise and Cobb County Hefty EnergyBag programs will be used by existing alternative energy recovery facilities which use non-combustion conversion technologies that convert non-recycled plastics to valuable resources such as oil, diesel and potentially chemical feedstocks thereby helping to minimize the extraction and processing of new virgin resources.

Energy recovery facilities that are approved to receive Hefty EnergyBag program materials must undergo a strict vetting process. With support from environmental consulting firms, the facilities are assessed based on facility ownership, financial stability, environmental compliance and permits, air pollution controls, facility operational practices, voluntary controls and analysis of the environmental impacts.

For example, the energy recovery facilities must hold applicable environmental permits and reports from environmental agencies, as required. These can include comparisons of actual emissions to current regulatory standards and industry best practices.

ADM Cleveland 2018 showcases the latest in robotics, automation, plastics, packaging and design engineering through 5 integrated events including Pack and PLASTEC. For more information, visit the ADM Cleveland 2018 website.

What are the basics of the energy recovery conversion process?  

Wooster: After the Hefty EnergyBag orange bags are collected, sorted and baled at materials recovery facilities, they are shipped to local energy recovery companies for conversion into valuable resources. Potential energy recovery outlets for the Hefty EnergyBag materials can include technologies such as pyrolysis, gasification and cement kiln facilities.

Energy recovery technologies that Cobb County and Boise will be using for their programs are complementary to mechanical recycling because they are able to capture the energy value of non-recycled plastics that would otherwise be thrown out and wasted in the landfill. Pyrolysis is a non-combustion conversion process that breaks down plastics into hydrocarbons by submitting them to high temperatures (350°C to 800°C or 662°F to 1,472°F) in an oxygen-free environment. Products of pyrolysis include oils, waxes, fuels and ultimately chemical feedstocks. The value of energy recovery outputs depends on the type of plastics collected and the price of competing energy sources. The recovery efficiencies vary with each individual process.Hefty outdoor bag bin

Do you expect these programs to continue to spread?

Wooster: Since we have proven the Hefty EnergyBag program works (i.e. that non-recycled plastics can be collected at curbside and at a quality acceptable for energy recovery outlets), we plan to gradually expand the program to other cities across the country.

Once energy recovery technologies are more widely used and accepted as valuable producers of liquid fuels such as diesel, the expectation is that this will lead to the acceptance and use of these technologies to produce a chemical feedstock which could be used to create new plastics.  Our vision is to expand the use of new technologies that lead to the advancement of the circular economy, which we strive for.

Where do U.S. efforts stand vs. similar programs in other regions such as Europe?

Wooster: The Hefty EnergyBag program, which is currently active in the U.S., complements mechanical recycling by providing a much-needed solution for plastics that currently cannot be mechanically recycled. The program enables curbside collection and conversion of these non-recycled materials into valuable energy resources. It is a significant step forward for the U.S. in achieving positive long-term environmental and economic advantages, including more alternative energy resources and fewer tons of valuable plastics ending up in U.S. landfills.

In certain parts of Europe, collection systems and treatment technologies for plastics are well-established and enable the integration of mechanical recycling with energy recovery. For example, in 2014, it was reported that plastics recycling and energy recovery reached an average of a 69.2% diversion rate in the EU28, Norway and Switzerland. Countries such as Switzerland and Austria are leading the way with the high recycling and energy recovery rates in excess of 95%, thereby minimizing the amount of plastics going to landfills.

Is this energy recovery solution the default process when other options are unavailable or impractical?

Wooster: Dow and the plastics industry are working to increase the amount of plastic packaging and materials that can be mechanically recycled by re-designing packaging where possible and by creating innovative new technologies that allow for increased recycling.

While mechanical recycling is the preferred solution for many post-use plastics, some plastics cannot be readily mechanically recycled because of material composition or lack of end users. In this case, according to the EPA’s Waste Management Hierarchy, energy recovery is the next best sustainable alternative. A range of energy recovery technologies are being used to complement mechanical recycling in order to help divert these valuable post-use plastics from landfills. These options complement each other and help realize the full potential of discarded plastic. While we are improving options for capturing value from used plastics, it is important to keep in mind why those plastics were used in the first place. The value in the use of the plastics will always be the primary driver of sustainability, and we must remember to keep that in mind as we optimize the value captured after the use phase is completed.

Where does this work within a Circular Economy model?

Wooster: As a global advocate for resource recovery technologies, Dow Packaging and Specialty Plastics is dedicated to sustainability through policies and programs that advance the vision of a circular economy for plastics, an important focus of the 2025 sustainability goals Dow set in 2015. Plastics are a valuable resource and through energy recovery we can recover their embedded energy content. There is no reason to continue to send plastics items that cannot be or are not being mechanically recycled to the landfill, when we can recover them to be used as valuable resources. The circular economy requires the input of energy and capturing the energy value from materials that would otherwise be wasted, which helps conserve resources that benefit all of us.

We have learned that energy recovery technologies, as supported by EPA’s waste management hierarchy, have a definite role to play in diverting non-recycled plastics from landfills. While most pyrolysis technologies currently produce an oil or diesel fuel output, the continued development and acceptance of these technologies is necessary for chemical recycling to occur at acceptable scale. This will help us achieve the ultimate circular economy goal of creating new plastics from materials that can’t be recycled via traditional mechanical recycling processes.

Our long-term vision for the Hefty EnergyBag program is that collected materials are used not only as energy resources but also for chemical recycling whereby new plastic feedstocks such as naphtha can be produced and used to make new plastics in a closed-loop system which satisfies the requirements of the circular economy.

How does this method of recovery compare to the TerraCycle model, i.e., programs that repurpose otherwise non-recyclable materials?

Wooster: At Dow, we believe we need a wide variety of technologies and systems to create a sustainable society. The Hefty EnergyBag program and other innovative recycling systems are complementary to traditional mechanical recycling. Many different types of recycling, repurposing and reuse programs can contribute to creating a more sustainable society by allowing resources to be used more efficiently.

Anything else to point out to PlasticsToday’s audience?

Wooster: While better management of used plastic packaging is an important part of improving our sustainability performance, it is essential to recognize that the use phase of the lifecycle is the most important contributor to sustainability. Our decisions about sustainability should always be based on the benefits and burdens across the entire lifecycle, not on a single phase. By allowing food, medicine and other products to be delivered safely to consumers by providing the needed protection, we are able to make a tremendous positive impact. We must all remember that packaging is an investment that protects the resources used to make the products inside it.

For more information, visit  http://www.hefty.com/hefty-energybag/faqs/

Source: https://www.plasticstoday.com/packaging/hefty-strides-made-recovering-plastic-packaging-energy-source/61044711558184

Determining Cooling Times

A crucial step in injection molding is cooling the plastic.  If the material is improperly cooled, it could affect the shape and size of the finished product.  However, not all materials are equal when it comes to the amount of time needed to cool down.  Learn how to calculate cooling times for materials in the article below.

What goes into injection molding cooling time?

Making Adjustments in Molding

Ever wonder what goes into the entire injection molding process?  Machinists have to make sure everything is set perfectly or otherwise the product can turn out very wrong.  As plastics are being molded, adjustments have to be made often to correct things or prevent mistakes from being made.  The article below discusses every factor that has the potential to be adjusted and how to do so if necessary.

The finer points of injection molding process adjustments

by: Garrett MacKenzie

on November 15, 2017

Processing in plastic injection can be a tricky business. It takes a strong and knowledgable approach toward process setup when adjustments are being made to a process. Materials respond in different ways to process change, and every adjustment needs to be made with a solid understanding that a part’s dimensions, aesthetics and even function can either be improved or degraded as variables are changed.

A good comparison to process adjustment in regards to machine response are old-style radios with knobs designed for both broad and fine tuning. One knob is used to aggressively adjust frequencies to get to the station you want. The other knob allows for fine tuning of a particular station.

Process adjustment is very similar. There are adjustments that can be made for fast and/or broad change(s) while establishing process, and other changes work better when making small adjustments to an established process. It is crucial to note that the time to be making major changes to a specific process is during the engineering phase of process development and validation.

This article outlines various changes available to processors when a process requires adjustment. Specific parameter changes and their potential outcomes, as well as specific problems to look for, are covered. The article also provides insights on how long it takes for specific changes to take effect.

Barrel temperature. Adjusting barrel temperature can be either a broad or fine change to process. It is important to remember that the best way to gauge the end result of a temperature change is by measuring melt temperatures. Melt temperature variation can result in a deterioration of the overall result even with a modest adjustment.

Great care should be taken to verify part function, aesthetics and dimensions. Some instances that may require barrel temperature change might be when viscosity is a suspect in the occurrence of defects or if process optimization is being attempted.

One important consideration to note is that these types of changes require time to allow the change to take effect. The best approach to verifying the result of temperature modifications is monitoring the change itself. If a temperature is raised or lowered, allow the temperature to first rise or drop or rise to the setpoint. You must then allow 20 minutes for the barrel to heat soak or cool to see if the change was successful.

Large temperature changes are best approached with the press idle. This prevents running scrap because of the length of time required for heat changes to take effect with a press in running condition. It is important to note that when a press is in running condition, it could take several hours for a large change to be confirmed as the actual molding condition.

Mold temperature. Much like the barrel temperature process, mold temperature also serves a dual purpose as both a broad or small change and changes cannot be ruled as good or bad without first allowing the mold to heat soak or cool for a minimum of 20 minutes after the setpoint has been reached.

The mold responds similarly to barrel temperature changes in that it could take a couple of hours for the mold to settle into the actual running state condition when large changes are made. Small changes can generally be confirmed 20 minutes after the setpoint has been reached. It should also be noted that mold temperature changes should be avoided until at least 20 minutes after startup to be sure that both the barrel and mold have reached a heat-soaked state.

Back pressure. Making changes to back pressure is generally a broad adjustment, resulting in larger changes to barrel temperature. While increasing back pressure raises barrel temperature and lowers viscosity, it’s important to remember that it also breaks down the material more aggressively, which results in shorter chains. This can adversely affect part strength. When making large changes to back pressure during production, it can take several hours for the barrel to soak or cool to a consistent result.

Cut-off. Changes to cut-off would be used for fine tuning a process, and are achieved quickly. After making the change, the result generally can be viewed by verifying that the cut-off position was made on the next cycle. Large changes to cut-off should only be made with hold and pack pressure removed to prevent tool damage. Hold and pack are added back into the process in increments following verification that the part fills out to 95 to 98% of total fill. The part should have a small, short or sink-like appearance prior to adding pressure.

Cool time. Cool time can be either a broad or fine-tuned change. Cool time effects can be verified 20 minutes after the change has been made, but larger changes may require more time for the overall result to take effect. Take note that longer cool times adversely affect cycle time.

Screw speed. Screw speed is a change that is used while fine tuning the cycle time of a process. The general rule of thumb is that the screw rotate time should be 1 1/2 to two seconds faster than the actual cool time setpoint. It is also important to remember that changes to back pressure can result in longer or shorter screw rotate times. Screw rotate time should be verified every time a change is made to back pressure. A screw that recovers too quickly can result in splay defects. Too long a recovery will affect the overall cycle time.

Mold and ejection speeds. Mold and ejection speeds are best made with the press out of production to prevent mold damage. Changes should be reviewed critically while cycling the clamp manually. Slower speeds will affect overall cycle.

In closing, both broad and fine-tuned changes are critical to process validation, and great care must be taken to prevent straying from the overall verified process. Any time a change is made, parts should be viewed as suspect, and proper precautions should be taken to verify that parts meet quality standards. Change results should never slow the overall cycle time, unless defect conditions exist that can only be corrected by lengthening the cycle time. Always remember that a single change can result in multiple outcomes, such as a temperature change resulting in burns and/ or warping or a pressure change resulting in flash or sticking parts.

Be sure that all personnel handling or inspecting the parts are aware that changes have been made, and identify potential hazards so they know what to look for. When process changes reach the desired effect, monitor the process for a full shift prior to changing setup data. As a scientific molder, it is important to review all process monitoring data to verify that changes are documented to ensure process validation has been accomplished.

Our goal as processors is eventually to reach our constant goal of zero rejects, 100% efficiency and repeatable success during startup and production. Repetitive manufacturing results in business success through process standardization and consistency.

Any changes to established processes should be viewed as suspect, and searching for a root cause is key to maintaining process consistency. Man, mold, machine, material or maintenance—the five Ms of molding—could be causing process deviation. Evaluate these areas prior to making any changes to a proven, validated process. A careful approach to process change will ward off many headaches and prevent poor-quality products from reaching the customer.

Source: https://www.plasticstoday.com/injection-molding/finer-points-injection-molding-process-adjustments/17906981557827

A New TPE series

The plastics industry encompasses much more than you think.  Almost every object you touch or see every day has at least one plastic component.  Your car, more specifically, has a lot of plastic parts – some of which are made with injection molding!  The article below discusses a new thermoplastic elastomer (TPE) series that can be installed around car windows.  Keep reading to learn about it!

New TPE series offers strong adhesion with EPDM rubber

At this year’s Fakuma in Friedrichshafen, Kraiburg TPE debuted a new series of thermoplastic elastomers especially developed for excellent adhesion and UV resistance in two-component applications with ethylene propylene diene monomer rubber (EPDM). The new Thermolast K compounds are intended primarily for automotive applications such as EPDM window trim and sealing profiles with molded TPE corner joints and end elements.

The automotive industry is the largest and fastest-growing market for thermoplastic elastomers (TPE). New applications exist for door and window seals, which require dimensionally stable corner joints and end elements. This has been achieved in the past with styrene-butadiene compounds (SBC) and crosslinked thermoplastic vulcanized (TPV) rubber. The cost-effectiveness of TPV is limited, however, due to diverse factors in the manufacturing process, in particular the window trim. The EPDM adhesion series from Kraiburg TPE offers a good alternative with added value.
“The production of diverse sealing frames and window trims consisting of EPDM profiles with molded corner and end elements requires new material solutions,” says Michael Pollmann of Kraiburg TPE. “The versatility of our TPE technology has made it possible for us to develop a competitive material that solves the phase separation problems of the systems that are currently used. In addition, we have the market expertise and customer orientation for fast implementation of such innovative two-component applications.”

The core requirements for corner joints and end elements of window trim profiles include excellent adhesion and weathering resistance, which are ensured by the long-term process stability of the TPE/rubber connection. It is also necessary to minimize the injection temperature of the TPE solutions in order to reduce the cooling and cycle times of the 2-component elements.

The AD/EPDM/UV series fulfils all of these requirements by combining optimal adhesion properties with long-term resistance to UV radiation and thermal effects with a hardness of 70 Shore A. Compared to competitive materials, these special TPE products exhibit superior stability. The EPDM profile is neither compressed, nor destroyed or deformed. The compounds feature uniform color fastness versus EPDM and there is no tendency of stickiness or phase separation.

Kraiburg TPE has examined the suitability of the new materials in comprehensive adhesion, weather exposure and thermal ageing tests. The processing properties and stability were optimized in close cooperation with the machine and mold manufacturers. “Our tests showed that the cleanliness of the EPDM contact surfaces with the TPE are crucial in these two-component elements and that freshly cut seal profiles result in optimal adhesion.”

The AD/EPDM/UV technology is already being tested by several customers in the automotive industry.

 

Source: https://www.plasticstoday.com/automotive-and-mobility/new-tpe-series-offers-strong-adhesion-epdm-rubber/70890623757682

Use of Plastic Bottles

Plastic bottles have been a topic of conversation for many years as people debate whether or not their use should be banned.  The argument for banning is in part due to the fact that if not properly recycled their waste harms the environment.  The blog post below discusses both sides of this and how the plastics industry has improved the design of bottles just recently.

Consumers should make sensible choices

Don Loepp | The Plastics Blog

Can we manage to use less stuff without resorting to bans?

The Trump administration took some lumps this month for reversing an
Obama-era policy that allowed a ban on plastic water bottles in national
parks.

Let’s take a step back and examine this from a common-sense point of view.

First, the ban itself was very limited. The National Park Service
adopted the policy in 2011, but the official stance was that the ban was
encouraged, but not mandatory. The policy had been implemented at just
23 of 417 park service locations. Also, the policy did not actually ban
plastic water bottles, but it did ban their sale.

Parks that went along with the ban had to install water bottle
filling stations and add signage letting visitors know where to find the
fountains. I assume those stations will remain, along with the message
to visitors that they should use refillable water bottles to help the
environment. That’s a great lesson that other public places, both
private and public, should emulate.

Also, the ban applied only to bottled water. Parks with the ban still
could, and did, sell other drinks packaged in plastic bottles, like
soft drinks. Why make it difficult for park visitors to drink water but
not unhealthy drinks? I acknowledge that’s also an argument in favor of
banning all drink bottles, but it’s still a valid point. If you’re
trying to reduce plastic bottle waste, why single out only one product,
and specifically one that’s healthy and important for the health and
safety of hikers and backpackers?

Finally, the target was supposed to be pollution, but it ended up
being plastic. Some national parks have a serious problem with litter.
But if water was sold in paperboard cartons, pouches, glass, aluminum
or, heck, paper bags, some people would still toss them on the ground
instead of disposing or recycling them properly. That’s a cultural issue
that needs to be changed.

This doesn’t mean I’m encouraging people to use single-use plastic
water bottles. I want to discourage everyone from buying them. Consumers
buy far too much bottled water and consume them even in places where
they can easily use a refillable container instead, like home and work.
Canteens and other refillable containers are the better environmental
choice; that’s a decision I make every day, and I hope others do, too.

But there’s a difference between encouraging the right behavior and
banning a product. There is a need for single-use packaging. Water
bottles are easy to recycle, and they have value to recyclers. And
today’s bottles are a lot lighter than bottles sold just a few years
ago, meaning they use a lot less PET resin.

I would like to see more states, or even the federal government, put
deposit systems in place to encourage recycling and discourage litter.
That would have a greater impact on the environment than the largely
symbolic policy that had been implemented in some national parks.

Loepp is editor of Plastics News and author of The Plastics Blog. Follow him on Twitter @donloepp.

Source: http://www.plasticsnews.com/article/20170831/BLOG01/308319996/consumers-should-make-sensible-choices

Efficiency of Non-Return Valves

Preventing leakage and improving shot consistency should be top priorities for injection molding professionals.  The non-return valve or check ring on machines plays a key role in this.  The article below dives into this topic and discusses new trends in injection molding that prevent leaks, etc., and also the pros and cons of new methods.  Continue reading and see if you should make adjustments on your machines.

Injection Molding: Time for Another Look at Non-Return Valves


First and foremost, they must seal properly, and check valves with stepped angles or radiused seats perform the best.


Columns Post: 7/25/2017
John Bozzelli

One of the most important details of the hundreds involved in injection molding is the non-return valve, or check ring. There are various versions of this—the three-piece, four-piece, full-flow, ball-check, etc. Leakage upon injection continues to be a problem, especially on small shot sizes. Most molders recognize the issue, but few do anything about it. But there have been some developments worth noting.

One gaining acceptance is two-stage machines. These have a screw to melt plastic and feed a plunger to make shot size; the plunger injects the plastic, much like a syringe. The tolerance or fit of the plunger and barrel is tight, providing less leakage and better shot consistency. Note that the plunger does not rotate. This works well but there is a trade-off for a larger pressure drop in the form of a longer and more complex nozzle body.

Yet another development has seen a switch from the “sliding ring type check valves (Fig. 1) to a “locking” ring type (Fig. 2). To be clear, what I call the “sliding” ring is where the screw rotates and the sliding ring does not; it only moves back and forth horizontally. Lately I am seeing most new check rings of the “locking” ring type. The ring still moves back and forth during recovery and injection, but it rotates with the screw as the screw rotates to make shot size. The ring is “locked” with the screw tip and rotates at the rpm of the screw as it builds the shot. I am not convinced the “locking” is a good idea.

What are my concerns? For starters, tolerances, barrel wear, and performance. The clearance between the ring and the barrel wall needs to be tight. You do not want the plastic to leak between the ring and the barrel wall. You want this to act like a syringe and not allow plastic to leak backward as we inject. Therefore, if this is a tight fit and it rotates at high rpm, aren’t you going to wear the front end of the barrel faster? Think of filled (like glass fiber) resins. Some may argue it is not a big deal for unfilled resins, but they will have to convince me that there are no problems with dirt, pieces of metal, other types of contamination, and unmelted or partially melted granules, especially with semi-crystalline resins. Most processors recognize that the non-return valve is a problem in molding. But, where is the research to figure out how to correct this so we make parts that are more consistent? I want valves cut and tested and then see resulting data. That said, let’s revisit what we have and what available technology might apply.

What is needed for a “good” non-return valve? The basic functions of a non-return valve are:

1. To allow plastic for flow through it—not over it—during screw rotation to develop the required shot size for your part. There should be no dead spots for the plastic to accumu- late or hang up. The flow path for the polymer should have minimum pressure drop and no shear stress due to sharp corners.
2. To provide a near-perfect seal so that upon injection this valve slides shut quickly and acts like the plunger in a syringe to push plastic forward into the sprue, runner, gate, and cavity, not allowing any plastic to slip back during injection, pack, or hold. We want it to seal under pressures up to 30,000 to 60,000 psi (2070 to 4140 bar).
3. To work properly on every shot.
4. To do the above without excessive wear on the barrel inside diameter. Note: It is possible that the non-return valve works properly but still does not hold a cushion due to wear on the inside diameter of the barrel. A better seal is made over a small area—not at mating or near mating angles.
5. To last at least six months to a year under normal use, understanding that some abrasive resins or filler will influence functional life.

As I’ve written in previous columns and said in every one of my seminars: It is critical that the check-valve seal not leak. How do make a good seal? Is it best to seal over a wide area or over a small area? Look at almost any container at home; take the cap off and analyze how the seal is made. You must admit these do a good job most of the time. Water bottles, sauce jars, you name it … they all have small contact angles and few failures. Granted, these are low-pressure applications; but at 20,000 psi, a seal is best made over a small or narrow area, not a wide area like 90% of all check valves.

Take a good look at the non-return valve, even a ball check, and you see we are sealing over a relatively wide area. So wide that if you have a glass fiber, piece of dirt, or even a partially melted granule, the injection pressure could lift the sliding ring or ball off its seat. This will result in a leak that will push molten polymer all the way to the feed throat after a few shots. This is not solved by locking the check valve; it is solved with a stepped or better yet radiused seat. A recent study showed the radiused check valve (Fig. 3) outperformed the standard by 87%.

We need a stepped angle or radiused seats to accomplish proper seal. The point being that a better seal is made over a small area—not at mating or near mating angles. A stepped or radius works and wears better. Some of my clients are seeing shot repeatability they have never seen before, with three times the life of a standard valve. Questions remain as to what radius is best and where should it go—on the seat or the ring? Our industry is the third largest manufacturing base in the U.S. and we need more and better fundamental research.


ABOUT THE AUTHOR: John Bozzelli is the founder of Injection Molding Solutions (Scientific Molding) in Midland, Mich., a provider of training and consulting services to injection molders, including LIMS, and other specialties. Contact john@scientificmolding.com; scientificmolding.com.


Source: Plastics Technology  http://www.ptonline.com/columns/time-for-another-look-at-non-return-valves