Fewer Layers for Fuel Tanks

Ixel polyarylamide (PARA) blow molding resin can be used for fuel tank systems for small off-road and garden equipment according to CARB and the EPA.

Sunroof frame for the Cadillac SRX produced by Inalfa Roof Systems Group. The one-piece frame (previous designs are an assembly of four parts) was produced with short-glass filled polypropylene using the MuCell process during molding. One benefit of the microcellular process is a 60% minimization of warpage compared to solid molding. What’s more, the frame has a weight savings of 12% and the number of tools and checking fixtures required were less, resulting in a savings of capital investment of about 50%.

The 2010 Alfa Romeo Giulietta that has a 1.6-liter diesel features a high-heat resistant charge air duct resonator made with a polyamide.

High-volume process has been developed for PUR coating thermoplastic parts such as interior trim pieces.

Underhood tubing can be made with a new PPA that is highly temperature resistant and comparatively easy to process.

When you have platen components like these for a 2,000-ton injection molding machine, local location is valuable.

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Although the approval from the California Air Resources Board (CARB) and the U.S. Environmental Protection Agency (EPA) for the barrier material from Solvay Advanced Polymers (solvayadvancedpolymers.com) for three-layer fuel tank systems specifies applicability for lawnmowers, snow blowers, weed trimmers, generators, and other small off-road equipment, it is probably worth noting that Ixef BXT 2000-0203 polyarylamide (PARA) blow molding resin has gotten the OK. The resin exceeds the CARB TP901 standard that limits fuel vapor emissions to 1.5g/m2/day for small off-road engines, and the EPA reg for CE10 ethanol.

The approval means that three-layer extrusion-blow molded tanks consisting of HDPE/Ixef/HDPE can be made instead of coextruded five-layer HDPE/EVOH tanks, thereby simplifying production.

Alfa Goes For “Acoustic Comfort”
2010 Alfa Romeo Giuliettas equipped with the 1.6-liter Multijet 105-hp Euro 5 turbo diesel feature a noise-dampening charge air duct resonator that is produced with a high-heat polyamide from DSM Engineering Plastics (dsmep.com), Stanyl Diablo OCD2100. The material is said to withstand more than 5,000 hours of exposure to up to 200°C with <15% loss in mechanical properties. Of the part being produced for Fiat by Hutchinson (hutchinsonworldwide.com), Maurizio Sevetti of the Fiat Group Materials Lab Plastic Unit said, “At Fiat we are committed to increasing the level of acoustic comfort, while at the same time protecting the environment by decreasing noise and increasing fuel economy. We found that thanks to its unique long-time high-heat aging performance, Stanyl Diablo OCD2100 was the only material we could approve for temperatures above 200°C for 3,000 hours.”

Plastic Process Can Improve Carbon Footprint
Can a plastic part production process help reduce CO2 emissions in a big way? According to research conducted for Trexel (trexel.com), the developer of the MuCell microcellular foam technology process, by Simply Sustain (simplysustain.com) that is most certainly the case.

First, the process in brief. MuCell—which can be used in injection molding, extrusion, and blow molding-involves metering in precise quantities of nitrogen or carbon dioxide into the component being made. As a result of the tiny cells within the component, there is a reduction in weight (as well as of material and production costs).

In one measure, 70 components, representing 194 lb. of vehicle weight, were assessed as to the effect of their being made with the MuCell process. In a second assessment, redesign for optimum use of the process was taken into account. In both cases, a cradle-to-grave analysis was performed.

Without redesign, there would be a savings of 15.7 lb. per car. For a fleet of 100,000 vehicles over a life of 150,000 miles, that would translate to a fuel save of 2.8-million gallons and CO2 emissions reduction of 29,155 metric tons.

For the redesigned parts, the weight save would be 35.4 lb. per car. That would translate for the 100,000 cars for 150,000 miles into 6.3-million fewer gallons of gas and a reduction of 64,971 metric tons of CO2.

Clear-Coat Process Developed
A new process for creating clear-coated components in a single manufacturing cell at high volumes has been developed by ENGEL (engelglobal.com/na) along with an Austrian company, Schöfer GmbH (schoefer.at) and Hennecke GmbH (hennecke.com).

Named “clearmelt,” it combines thermoplastic injection molding and thermoset polyurethane (PUR) reaction injection molding to produce parts like interior trim pieces.

In a typical operation with a sliding-platen two-cavity mold, a thermoplastic sub-strate is molded while the empty mold cavity is sprayed with a PUR mold release agent. A clear PUR coating is injected onto the thermoplastic part, which is then cured. And it continues. A multicavity rotary-platen mold can be used to increase production. Coating thickness of less than 0.5 mm can be achieved.

Plastic Tubing for Underhood Apps
Another metal-to-plastics underhood application is being facilitated by the development of a new high-temperature polyphtalamide (PPA), Rilsan HT from Arkema (arkema.com), that can be used for tubing applications. It is said to reduce overall system costs by up to 50% compared with metal tubing assemblies. The resins can be processed on standard extrusion equipment. It is also available in injection-molding grades for the production of connectors.

Learning from Others
“Although automotive is generally considered to be a high-volume industry, it isn’t anything compared with caps and closures,” observes David E. Lawrence, president, Plastics Machinery Injection/Extrusion and Mold Technologies, Milacron Inc. (milacron.com). “It’s not unusual to see a 128-cavity mold making bottle closures. It looks like its raining caps when the mold opens.” He says that one customer makes a billion caps per month.

That said, he believes that there are things that can be learned by auto from other industries—although molds with 128 cavities may not be one of them. (That is, given the demand for caps, the molders have the ability to put a whole lot more money into their molds than is likely to be the case for automotive molders.)