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Articles from 2009 In October

Streamlined SPC

The latest version of SPC software from Zontec (Cincinnati, OH) incorporates a dozen new features, enhancements, and program improvements. Version 8.0 of Zontec’s Synergy 2000 package streamlines many routine program operations, making these tasks much more efficient, and adding greater usability. Among the enhancements are faster setup options for parts, processes and quality characteristics, and templates that assist in the creation of ID and note tags for traceability, assignable causes, and corrective actions.[email protected]

Precise nozzle pressure

Melt pressure in front of the injection screw is an important process parameter for precision processing and machine control is critically dependent on its precise measurement. This is because injection molded components can only be kept within extremely tight tolerances if this pressure can be accurately and repeatably measured and recorded over an extended period. In this respect, the new melt pressure sensor Type 4021A from Kistler (Winterthur, Switzerland) is said to be a groundbreaking new development based on the piezoresistive principle of measurement. It measures this important machine parameter directly in the area in front of the screw with reproducibility errors of —[email protected]

Coordinating an acceptable transfer, Part 2: The toolroom manager

In Part 1 of this series, a tooling engineer is notified that 30 molds are to be transferred out of his facility to another location. This is a longtime customer and it is hoped that other projects will continue, so a well-executed plan must be in place to ensure a successful transfer. After getting an initial plan started, it’s now going to the toolroom manager for the majority of the implementation steps. 

The toolroom manager knows transferring 30 molds is no small feat. He also knows he has to report back to others with the transfer plan and how it’s going to impact other customer jobs and the company at large, so quantifying time and costs involved with the help of the toolroom manager is critical.

Before starting any transfer process, the toolroom manager must address specific issues with regard to the tools being moved, including determining whether there are any molds still running. If not, then his team can more easily coordinate the transfer. However, chances are that at least some of the molds are running against a purchase order, and it will be important to find out when the orders will be complete, as this will help determine when the molds can be shut down to make the transfer deadline. Also, what are the shipping dates for the parts?

Mold weight, which can vary from unit inserts of a few hundred pounds to large molds that are thousands of pounds, is a big consideration, as it directly relates to total volume of molds being moved and how many shipments may be required.

Spare components typically are part of a proper tool transfer and will need to be located, cleaned, labeled, and packed for shipping. This is also true for any automation equipment, such as hot runner controls and cables, robots with end-of-arm tooling, sprue pickers, custom chutes, shields, and other part-containment items. They are considered to be auxiliary items to the mold and it should be verified that these are to be inventoried and packed.

How much information will be communicated back to the OEM? Ideally, documentation from the mold’s life will contains the following items:

• Spare component inventory
• Processing data sheets

• Injection mold/cavity layout sheets
• Water hookup diagrams

• QC reports

Article drawings, mold drawings, and last shots should also be provided so the receiving plant has everything it needs to enable a successful startup.

The molds themselves should be cleaned and protected against corrosion. PM documents should be updated as to any maintenance issues. If the molds are due for service, they should either be serviced, or it should be noted that service is due for the recipient of the tool. If service is up to date, then basic preparation and protection of the mold is sufficient.

“Here is where a proper maintenance and documentation system can pay great dividends to a molder,” says Steve Johnson, operations manager at ToolingDocs. “When established correctly, it will be possible for the recipient of the mold to make sense of what has been done and when, which reduces the ‘maintenance learning curve’ by thousands of dollars. Scribbling ‘fixed mold’ onto a work order only communicates a lack of organizational integrity.”

After the toolroom has completed its responsibilities, the tooling engineer will report back to the plant manager that everything is assembled, documented, properly packaged, and ready to ship. By providing this information, the plant manager has the records he needs should any issues arise at the receiving plant when the molds are sampled.

One will often be shocked to learn how many actual hours are spent in this entire process and how this disruption can impact a manufacturing operation that is working to be lean. In this example transfer, the total shop time required could amount to hundreds of hours for the 30 tools to be ready for shipment. But the dividends are realized at the receiving side, with tools that have less unknowns and are free from damage.

Coming next: The receiving team—getting organized and documenting items when the molds arrive.

Author Randy Winton ([email protected]) is global training manager at ToolingDocs.

What are the hidden risks of tool transfers? Part 2: Assessing risk in part design

Believe it or not, the design of a part has an important impact on a tool transfer.

It’s important when bringing a new part from the design stage to the first part out of the machine that the right steps are taken. I can remember a few troubled molds that had very small processing windows and could only run in one machine. This happened because the designer missed some of the crucial elements in the process of part design. The one thing you must understand is that the customer doesn’t always know what’s best. In most cases, what is a functioning part is not always one that we as molders can manufacture very easily. 

The first task in assessing risk in your part design is understanding how mold details affect the plastic. Take, for instance, how molecules react around these details. Let’s break it down a little further. In order to get the plastic into the mold, we need it to flow from the injection unit to the cavity. The melt takes whatever route we provide in the mold/part details to get into the cavity. Since plastic is a non-Newtonian fluid, we know that we can change the viscosity 100 times more through flow rate than anything else. Also, since plastic is compressive (and not hydrostatic), it does not transmit energy very well. I like to relate this to a sponge, because if you apply pressure to the center of the sponge, the energy does not transmit equally to the sides. Figure 1 shows how the molecular chain reacts during flow.

Figure 1: Molecular chains

Figure 2: Sharp corners

Figure 3: Warp conditions may occur due to sharp corners

Figure 4: The importance of draft in the part design

Figure 5: The problem with non-uniform wall thicknesses

Figure 6: Rib considerations

Figure 7: Ensuring the measure of things is paramount in GW Plastics’ precision molding practice.

Figure 8: Creating a successful part design

Image A represents the polymer chain at its most relaxed state, without flow. During this time, the polymer chain is coiled up onto itself. The viscosity is at it highest in this state. When the viscosity is high, the plastic is more compressible and it transmits energy poorly.

Image B represents the polymer chain during the molecules’ normal flow. The polymers align themselves, allowing better flow and better energy transmission. The viscosity is lower, giving molders better control over the flow portion of the process.

Image C shows how the polymer chains react with a fast injection rate. Here, viscosity is very low and the material flows easily. However, it does pick up some frictional heat. Imagine holding the ends of a rubber band in your hands and place the center of it between your lips. Now, really fast, stretch and contract it. Repeat this several times without stopping. What do you feel? Heat is generated, much the same way plastic reacts when you stretch and contract the chains. The next step will shed some light on the subject.

In determining risk of your parts, you need to think about how you will be treating the plastic in the cavities. Take the following steps in “risking” your part design.

Step 1: Sharp corners
Sharp corners can cause a few issues in the final product. Stress in the corners causes a weakened condition, burns, sinks, and shrinkage, especially in thick-walled parts. One of the jobs I faced was a five-sided box, about 2 inches high, 1 inch wide, and 1.5 inches deep. The customer had moved this job to multiple companies because the molders failed to hold a crazy specification on warp: less than 0.002 inch using PET. The mold was a hot runner, low-voltage, internally heated manifold. We tried everything under the sun, including making cores that were bowed in the opposite direction. The only thing I fell short on was looking at the part’s sharp corners. This mold could only run in “press 6,” since it was the newer machine. We had some production runs that went very smoothly and others that were a nightmare. It wasn’t until I took a class at RJG 10 years ago that the light finally came on and explained the problem: The sharper the corners, the more stress concentration there is. 

Let’s take a closer look at the sharp corners shown in Figure 2. You can see how three different viscosities of material are flowing through the cavity. All three react differently with flow and packing, not to mention the shear heat the polymer picks up around the corner. What we know about this scenario is that the material flowing around the corner is not consistent.

Let’s add another concern to this—cooling. We have a core that shapes the interior of our part and a cavity that shapes the outside. The problem lies in the corner’s cooling capabilities. You must consider where the heat is being generated. The inside corner has only one cooling capability, where the largest content of BTUs is being generated, while the cavity block has four cooling capabilities, where the least amount of BTUs is being generated. We have now encouraged uneven cooling, creating a greater variable, as well as a variable shrink rate. Inside sharp corners take longer to cool, while the outside cools very quickly. This causes a conflict in cooling rates, and either will void in the center wall section or sink on the outside of the part—or both. 

To understand the full impact of this problem, we must understand what most process technicians would do to correct the sink and void problem. Typically, when these defects detected, the process tech raises the pack and hold pressures, maybe even profiling them to iron out the quality defect. The problem is, we have now increased the density of the plastic in that area, as well as in others. When the density goes up, the shrink rate goes down. It shrinks less, so the part is too big. Pressure losses across a part can be great, and therefore higher pack and hold pressure is not the same everywhere in the part. Pressure is typically highest near the gate and lowest farthest from the gate; it is not linear. Many times, the approach to this is dictated by the talents or knowledge of the process tech.

The problems escalate when we try to transfer this mold to another machine. If the waterlines are connected differently, or the water flow varies, you will not make the same part. If your machine is not tuned the same as the first machine, in this case for injection speed, you will change the shear rates and the distribution of the plastic when injected. If you do not posses the same talents that were used in tweaking the process to get the approved part, you may not make the same part.

If you are making a noncritical dimensional part, this may not be a big deal to you. However, in my case, it was huge. From a scale of 1-5, 1 being the best situation and 5 being the worst, I would rate this corner a 5 (see Figure 3).

Step 2: Draft
I cannot tell you how many times I have run across transfer tools, or even new molds we built, where the customer asked for no draft or even a reversed draft. You and I know that plastic needs some draft to come off the cores. I had a mold making cylinders that were 8.00 inches long and 3.00 inches in diameter, with no draft. The material was a wide-spec polypropylene. The designer went with the customer’s request to have no draft on the part. No matter how fast or how slow we ran the mold, the part would just fold inside-out. The fix? We had to make new cores, at close to $5000 each, with draft on them. We added 2° draft and explained to the customer that this was needed in order to manufacture the part.

Another thing people seem to overlook on the jobs I have consulted with is the draft for the details or for additions and subtractions to the walls. The risk for this job was easily a 5. However, after we added the draft, the risk went down to a 3. There were still risks of sticking during startup, due to only having 2° of draft. But since we had to compromise because of the functioning aspect of the part, that was all we could do (see Figure 4).

Step 3: Nonuniform walls
It is important to verify that you have nominal wall thicknesses across the whole part. If you have a solid model program, it would be easy to draw a circle within the wall sections where the circle would make a two-point contact and drag it around the part geometry to make sure the walls are consistent. In Figure 5, you can see how, in the thicker sections of the walls, you would have to draw a larger circle in order to make the same contact as the thinner walls. In these sections, you may have issues packing out sinks. You may get voids, shrinkage, and many other problems. 

The example in Figure 5 is a five-sided box with all of the problems you may face. This box is a housing for a signal relay that goes into a truck.

1. Sharp corners

2. Thick-to-thin sections
3. Thick-walled additions

If I rated this part as it stands, I would have to rate it a 5.

Step 4: Additions and subtractions
Additions and subtractions should be considered throughout the part design phase, as there are rules that need to be followed. In Figure 6 we will talk about three major rules that should be considered during the additions phase.

Figure 6 shows how the rib thickness should be no thicker than half the wall thickness (6A). I once ran a battery housing made of a fire-retardant Cycoloy material. With ribs that were more than half the thickness of the part’s main wall, we were unable to pack out the sink. I remember trying every trick in the book to get rid of these sinks. Finally, the customer did allow the sink and we were able to run the job. However, every once in a while the sink would get worse due to viscosity shifts in the material.

The diagram also shows that ribs should be placed at a distance that’s a minimum of two times the part’s main wall thickness (6B). If you bring the ribs closer than that, there is a chance of getting defects like sinks and voids. I have even run across issues of sticking on the core, since it is harder to add sufficient draft on these ribs when they are too close.  

Any time I get a call from a client about short ribs, the first questions I ask are, what is the melt index of the material? What is the thickness of the part’s main feeding wall (6C)? And how high is the rib? Almost every time, the rib is much more than three times the thickness of the part wall. Remember, when we close the mold, air is occupying the space between the cavity and the core. Air is also occupying the space in the rib detail as well. We can add venting on the parting lines and in knockouts, and possibly in mold details, but it is very hard to vent ribs. Also, plastic will always take the path of least resistance.

Now, let’s look at the five-sided part in a solid model for the truck turn signal relay (Figure 7). My risk rating of this part design before changes were made is shown in Figure 8.

Let’s sum up the scores of our examples. Out of a total of 35 points for a total high-risk situation, we received a score of 27 points for the part design. To me, this job would not be accepted through the design phase as the score is pretty high. Typically, anything higher than 15 can be in question; however, I do have customers who are even more critical than I am. After all, we don’t get paid to make constant tool adjustments.

Sharp corners    5

Draft    5

Nonuniform walls    5

Additions and subtractions    12

Total    27 points

After modifying the design of the five-sided box, we can create a successful part design (Figure 8, after) that will allow the processor to have a greater processing window.

So, how does this help us? We all have been in situations of tool modifications because critical elements were overlooked up front. Some modifications may have been small while others may have been very costly. If we can think smarter up front in the part design phase, and think about it in a sense of the plastic’s point of view, we can eliminate those costly mistakes. Let’s put this a different way: How costly is it to change a drawing vs. cutting or replacing steel?

Missed Part 1 of this series? Find it here.

And there’s more: Part 2 of “Coordinating an acceptable transfer” covers the toolroom manager’s responsibilities.

Author Dan Clark ([email protected]) is a Consultant/Trainer with Scientific Molding Implementation Specialists RJG Inc.

More on this topic:
What are the hidden risks of tool transfers? Part 1
What are the hidden risks of tool transfers? Part 3: Noninstrumented tool transfers

RocTool, German institute work together on inductive heating

One of the more significant developments at the Fakuma tradeshow earlier this month likely fell below most processors' radars as the developers of two technologies for inductive heating of injection molds agreed to partner, a move that could encourage the technologies’ already swift-growing acceptance.

There was reason for concern as both have interesting but similar technology, similar enough that a patent dispute could have ensued and prevented the processing community from showing interest in either. Instead, the two—RocTool (Le Bourget du Lac, France) and Germany’s plastics institute in Lüdenscheid (German acronym KIMW)—will work together, with RocTool acquiring the KIMW’s patents and the institute agreeing to continue its development work while also promoting both outfits’ products in Germany, Europe’s largest injection molding market and one open to innovation.

Joining KIMW’s Stefan Schmidt (center) and RocTool’s Alex Guichard (right) is Korbinian Kiesl, owner of injection molding machine maker, Billion, which hosted RocTool at its stand at the Fakuma tradeshow.
MPW has reported on both of these and their developments before, including this article. Inductive heating is not new, but both RocTool and the KIMW have advanced it significantly. The gist of induction is that electricity, and not water or oil, is used to rapidly heat an injection mold’s surface. Because only the surface of the mold is heated, cooling also can be done rapidly. The combination of rapid heating and cooling helps prevent warpage and makes for better surface appearance.

The German partner’s Indumold technology involves use of an inductor inside an injection mold, while RocTool’s Cage system forms a cage around a mold’s exterior. Indumold is already in commercial use, says Stefan Schmidt, managing director in Lüdenscheid. RocTool actually only changed focus to injection molding in 2008 but sold 16 licenses in 2008 and expects to sell about 20 this year. Prior to 2008 the company had worked almost exclusively with processors of thermoset composites.
On an injection mold, RocTool CEO Alex Guichard says a Cage-equipped mold’s surface can be heated about 100ºC in just 6-10 seconds; Indumold gets you that 100ºC change in temperature in just two seconds, says Schmidt. Injection of the melt is onto this hot surface, with water then used to rapidly cool the mold. Because the inductive heating only affects the mold’s surface, cooling can be focused just on that and not be wasted on the rest of the mold.

Guichard and Schmidt say the path to partnership was forged as both businesses began to compete on some projects. Generally, though, Indumold makes more sense for parts with deep cuts, and the Cage system is better for large panels. Patent concerns also played a part, as did Guichard’s realization that it would take a German partner to be successful in that country.

RocTool acquired the IP, patents, brand name and know-how surrounding Indumold and will now license the process as well as its own. The Lüdenscheid team will demonstrate RocTool’s technology at their facility and help introduce it to Germany; the KIMW also received an ownership stake in RocTool. RocTool, though a small company, has a presence in Japan, the U.S., and soon Taiwan and India, offering opportunity for Indumold to see use far afield from its German roots, says Schmidt. “The next challenge,” he says, “is to get the cooling (on an inductively heated mold) to be as rapid as the heating.”

Inductive heating is not for every molding application as there is a cycle-time penalty. The technology is of interest for system costs reduction in the processing of parts which, after molding, require coating, painting, or other surface enhancement. The rapidly heated mold surface causes parts to form with no weld line and often with a near-mirror surface.

Guichard adds, “So far, most of the emphasis has been on parts with a top surface finish, but the future will be more use of the rapid heating for high-temp materials” such as polyether etherketone (PEEK). Impressive at the Fakuma tradeshow in October was a large (60 cm by 50 cm; 900g) PEEK part, 2.2 mm thick, that RocTool displayed. The panel was molded with a single injection point, demonstrating how the heated (330ºC in this case) mold surface positively affected melt flow. “If you can change the flow, you dramatically change the injection molding business,” said Guichard. Matt Defosse

Nypro sells Chihuahua site to Fortis Plastics

unit, a injection molding and extrusion business that formed in late 2008 through acquisitions from Leggett & Platt Inc. and Atlantis Plastics Inc. Fortis currently operates a resin compounder and eight regional molding facilities, including an operation in Ramos, Mexico.

Nypro Chihuahua’s nearly 100,000-ft2 facility features, injection molding. painting, decorating, and cleanroom capabilities. According to a release, Fortis hopes to expand the site by “extending its products and capabilities to Fortis’ current customer base of appliance, medical device, building products, and furniture makers.” Fortis currently employs 950 at facilities in Fort Smith, AR; Carlyle, IL; Poplar Bluff, MO; Henderson, KY; Jackson, TN; South Bend, IN; Houston, TX; and Ramos and Chihuahua, Mexico. Monomoy operates a $280 million private equity fund and has completed 25 transactions in four years. It now owns 10 business that collectively employ more than 5000.

Nypro Chihuahua serves the electronic/telecommunications, consumer, industrial and automotive markets, with 250 employees, 42 injection molding machines, including eight in a Class 100,000 cleanroom, manual assembly, painting, and a metrology lab. Nypro maintains three other operations in Mexico. The newest is Nypro Juarez, established early in 2007. That site has 72 molding machines, ranging from 45 to 600 tons, with a Class 100,000 cleanroom. In Guadalajara, Nypro Kanaak Guadalajara operates a 140,000-ft2 facility in the heart of Mexico’s “Silicon Valley.” A joint venture between Nypro and Sealaska, the site has paint and decoration services, including a Class 100,000 clean painting room, with two fully-automated booths. Finally, Nypro Monterrey has 75,000-ft2 of production space, with two molding rooms—one housing 25 machines, and the second, a Class 100,000 cleanroom, with 19 presses. [email protected]

Dumping penalties imposed on PE bags from Indonesia, Vietnam, and Taiwan

On March 31, 2009, bag makers Hilex Poly Co. LLC (Hartsville, SC) and Superbag Corp. (Houston, TX) petitioned Commerce to investigate the alleged dumping, and on May 14, 2009, the U.S. International Trade Commission (ITC) voted unanimously that the domestic bag-making industry was materially injured by the dumped imports.

Going forward, importers of polyethylene retail carrier bags from Taiwan are now required to cover the estimated antidumping duties through a bond or cash deposit. Once the preliminary determinations are published in the Federal Register, which should happen within the week, importers will also have to post bonds or pay cash deposits for plastic bags from Indonesia and Vietnam. In addition, U.S. Customs and Border Protection will suspend liquidation of those entries pending Commerce’s final determinations in the investigations. Those investigations must be completed within 135 days, and the ITC will make a final determination within 180 days. If Commerce and the ITC each make affirmative final determinations, antidumping duty orders will imposed in March 2010.

According to ITC data, the volume of bags imported from Vietnam more than doubled from 2006 to 2007, exploding from just over 3 million to 7.28 million in 2007. Last year, they dropped down to 7.19 million bags. The increase from Indonesia was similar, with 2006’s imports of 1.59 million jumping to 3.39 million in 2007, before dropping to 2.81 million in 2008. Taiwan’s imports increased from 2006 to 2007 as well, rising from 2.17 million to 3.98 million. Unlike Indonesia and Vietnam, they continued to expand in 2008, hitting 4.57 million. The dollar value of imports of plastic bags from Vietnam, Indonesia, and Taiwan in 2008 were $79 million, $38 million, and $51 million, respectively. Tony Deligio

September 2009 OESA Supplier Barometer shows uncertainty

(OESA) released September’s survey, in which 100 OESA member companies participated with 112 responses. While there is confidence in the short term among Tier One and Tier Two suppliers with respect to capital to fund their businesses, smaller firms are less confident in their ability to access necessary capital for equipment acquisitions, M&A opportunities, and program consolidation leads. Of the respondents, only 5% said they were “significantly more optimistic” about conditions in the industry, while the vast majority, 74%, said they are only “somewhat more optimistic.”
A continuing thorn for suppliers is the ongoing contention between them and OEMs over the issue of progress payments for tooling programs, which, the survey summary points out, is also an issue for bankers as program cancellations, payment delays, and volume volatility injects significant risk into the equation. Suppliers note that better working relationships that include timely progress payments could reduce costs overall. “It appears a customer might get a competitive advantage with better access to technology, greatly improving costing accuracy and a quicker response time from its suppliers” by improved working relationships, said the survey.
The Cash for Clunkers program boosted the OESA Automotive Supplier Barometer Sentiment index, lifting it a full 10 points to 72 in September. “However, the respondents sprinkled their comments with phrases such as ‘a blip’ and ‘too early to celebrate’ such that it is easy to see there is a great amount of reserve in the spike in production schedules,” said the survey summary.
Suppliers are trying to adjust to the “new normal” with cost cutting and restructuring toward a much lower break-even point, with the median break-even unit level for this group of respondents at 9.5 million units (vehicles). Respondents estimated 2010 North American production volume will be 10.1 million units, which means that even with a modest increase in production, suppliers, on average, should be above their break-even point next year, the survey concluded.
Of those who were “significantly more optimistic” about conditions in their businesses improving, one respondent said, “NA sales and production have hit bottom. Even though sales are at dismal levels, inventory is down and fleet demand should improve, boosting production above break-even points, at least for the balance of the year.”
Some respondents took advantage of the weakness of some of their competitors, commenting, “While competitors were cutting back, we became much more aggressive. Increased effort resulted in two business awards.”
Of those who were “somewhat more optimistic,” one respondent said, “New program awards have provided our company with some optimism, but the overall over-capacity in our industry coupled with uncertain future sales demand keeps our optimism in check.”
When asked how their calculated tooling cost of capital and overall tooling costs would change if the customer provided tooling progress payments, 33 respondents said it would result in a “slight reduction” (no, or under 5%, cost reductions). “Not significantly,” said one supplier. “We have shifted the burden to suppliers and are using EDC financing. Maybe a few percent pick-up.”
Only three respondents said it would “significantly change” the cost to capital (greater than 10%), and one noted, “The cost would be reduced by at least 30%.”
There were 25 responses to “no change” or “not an issue.” One respondent commented, “Assuming a nine-month tooling lead-time to PPAP, very little to zero. It’s so competitive right now that for standard lead-time tooling there is very little cost of capital allowed in the tooling bid.”
Five respondents said that it would improve cash flow, with one commenting, “Since we currently fund $5-$10 million in customer tooling costs at any point in time, our cash flow would be significantly improved (note: our annual sales are just over $100 million).”
Five respondents said they are already receiving progress payments. “Customers already give us 40/30/30 progress payments in most sectors,” commented one.
Overall, the majority of respondents (50) said that the working relationships could be vastly improved if the issue of progress payments were not such a hurdle. “The relationship would see major gains,” noted one respondent. “A HUGE portion of the customer relationship is burdened by conversations about program risk, volumes, investment recovery, etc.”
Another respondent commented that the working relationship would “improve greatly,” and the pressure on the supplier reduced significantly. “The environment is changing and suppliers can no longer fund major capital or tooling expense without advances or progress payments,” they said. Clare Goldsberry

Materials: Impact modifier helps TPOs balance stiffness, toughness

Dow Chemical (Midland, MI) is in the process of commercializing a new impact modifier for rigid thermoplastic olefins (TPOs) that will increase their flexural modulus without affecting low-temperature impact resistance, allowing designers to downgauge parts without sacrificing mechanical properties. In a paper presented at the Society of Plastics Engineers’ Automotive TPO Conference, Dow’s Kim Walton said the new impact modifier, which will join the Engage family of products, showed 15-20% greater impact efficiency than best-in-class commercial ethylene/1-octene copolymers, with equivalent low-temperature high-speed dart impact results and 15% higher modulus as SEBS block copolymers in TPOs at equivalent levels.

In late October, Dow Chemical Market Manager Dave Mitchell told MPW that the latest member of the Engage family had completed internal testing, and was currently being validated at several automotive customers, with commercialization expected in the fourth quarter. Walton and Mitchell said the impact modifier’s higher level of performance is primarily derived from improvements in its compatibility with polypropylene (PP), allowing what they call “optimum dispersion” and a greater balance in stiffness/toughness properties.

At the SPE event, and in other communications with automotive customers, Mitchell and Walton said that lightweighting is top of mind for many in the sector, driven by heightened fuel-efficiency standards. In internal simulations, Dow has found that for certain parts, a TPO with its new Engage impact modifier could downgauge by 5-10%. “In real terms,” Mitchell said, “you think about bumper fascia, which have an average weight of 25-30 lb; if you can get to a 10% reduction, you’re talking about 3 lb of material, and that’s a significant change for the industry. The industry sees every pound as a pretty significant shift.”

In addition to allowing lightweighting, Dow also believes the new impact modifier could allow greater adoption of plastics in a vehicle exterior due to its effect on TPOs’ coefficient of linear thermal expansion (CLTE). “I think the other trend we see in the marketplace is the desire to use plastics in more places,” Mitchell said. “One of the major things folks are doing is beginning to look at is, ‘How do I wrap further around the car?’”, targeting parts like rear fenders, which traditionally have been steel. “This product has a reduction in CLTE as well, which we think will also help with design and let our customers get into the different areas, get into the rear portion of the car.” Matching steel’s CLTE and allowing better fit/function has been a barrier to plastics in some automotive exterior components. Tony Deligio

Names in the News: PTI’s Tom Brady recognized by SPE blowmolding group

Thomas Brady, founder of Plastic Technologies Inc. (PTI; Holland, OH), was recently awarded the 2009 Lifetime Achievement Award by the Society of Plastic Engineers’ (SPE) Blow Molding Division in recognition of achievements large and larger over the past decades.

Brady’s work at PTI may well have merited the recognition on its own. Formed in 1985, PTI has grown to be recognized as one of the plastics packaging industry’s leading technical development services for companies interested in starting or expanding their use of polyethylene terephthalate (PET) packaging, especially blowmolded bottles. The companies he started employ 200 from locations in Holland and Bowling Green, OH, as well as Yverdon, Switzerland. A spin-off company has become one of the country’s leaders in PET recycling.

Thomas Brady
Prior to founding PTI, Brady was vice president of plastics technology for Owen-Illinois, Inc. (O-I), where he led the development of the first PET soft drink containers. His team was critical in study of molecular orientation in PET during stretch blowmolding. The culmination of this pioneering work was the introduction of the first continuous rotary reheat stretch blowmolding machine in the U.S., which effectively cleared a path for PET to replace metal cans and glass jars and bottles.

“I thank SPE for this prestigious honor. I also would like to thank all of the employees at PTI who have made the company the plastics packaging thought leader it is today. My family also has played an important contribution. Their continued support throughout my career encouraged me to forge new paths,” Brady said.

Phoenix Technologies was formed in 1992 and is now one of the largest global recyclers of PET for bottle and blowmolding applications.

Brady, who earned his Ph. D. in plastic materials engineering from the University of Michigan and his master’s and bachelor’s engineering science degrees from Dartmouth College, is now serving as interim dean of the University of Toledo’s Judith Herb College of Education. [email protected]