Engineers, designers and companies affected by emission guidelines need to stay well-informed and ahead of the game, according to several officials who spoke during the Society of Plastics Engineers' Annual Blow Molding Conference, held Oct. 12-13 in Chicago.
An official with Mergon Corp., based in Anderson, S.C., laid out a time line for when some products will fall under new guidelines from the Environmental Protection Agency. In 2010, new standards affected products under the SORE (small off-road engines) category, including hand-held devices such as string trimmers, leaf blowers, chainsaws and edgers. Several non-hand-held products were covered under 2011 standards, including walk-behind mowers, generators and pressure washers. Into 2012, riding mowers and zero-turn mowers will fall under the standards.
The challenge is to find monolayer technologies to meet barrier properties, said Mergon's Steve Thompson. Formerly, barrier property requirements were met by other means — such as multilayers in automotive fuel tanks and fluorination technology in SORE fuel tanks.
But multilayer is a high-investment technology with limited flexibility and is suitable for high-volume production. Fluorination technology use in high density polyethylene blow molded containers is limited because there are additional freight and handling costs, an additional supplier is needed, and its ability to achieve future regulation changes is questionable, as is the cosmetic finish of the tank.
Mergon does use fluorination technology in a facility in South Carolina, Thompson said.
Options in monolayer technology include Hyperier, a proprietary barrier resin from South Korea's LG Chem Ltd.; an Enbarr LLC nylon material combined with nano-barrier technology; and Ticona's Hostaform, which reportedly has been used successfully in blow molding small gas tanks. Officials currently are awaiting permeation and test results.
Options in two- or three-layer technology include Enbarr's ethylene vinyl alcohol-based Tievoh, for three-layer structures and Solvay Plastics' Ixef for two- and three-layer structures. Ixef started trials in 2007 using Mergon's specialized blow molding machine fitted with three extruders, enabling a three-layer parison. That material was difficult to process and has since been reformulated, with test results pending.
Ford Motor Co., for its part, is pursuing advanced blow molding technologies primarily focused on complying with evaporative emissions standards, optimizing product design and reducing design complexity.
Evaporative emissions standards are changing, said Ford CAE manager Mohammad Usman. “We are aggressively looking at this,” he said. “What worked in the past is not going to work. We're going after new technology.”
That includes twin-sheet blow molding. Other technologies include three-dimensional blow molding for ducts and hoses. The company also is changing the way it blow molds foam ducts. Via traditional blow molding, there was the extra operation of adding a layer of foam. Through new technology, Ford performs in-mold addition of the foam layer. The company also is suction blow molding several products including air ducts, turbo hot-charge ducts and a fuel filler pipe that is in development.
Usman said suction blow molding provides high flexibility in complex article geometry, improved wall-thickness distribution and better surface appearance. Ford also redesigned and converted a fuel manifold from injection molding to blow molding to address failure due to high pressure, he said.
At John Deere's technology innovation center in Moline, Ill., Ken Carter, staff materials engineer for polymers, is looking way ahead for fuel-tank requirements and is encouraging everyone else to do the same.
The California Air Resources Board is enforcing its requirements in stages and each stage takes three to five years.
“CARB right now is evaluating lawn and garden,” he said. “It will probably be next year, but the trend is to lower it. … So by 2020, who knows where CARB will be,” Carter said.
In addition, Carter encouraged officials to be aware of new fuels on the market, such as the controversial E-15 — a blend of gasoline and ethanol. As of Aug. 10, E-15 was not registered with the EPA and is therefore not legal for distribution or sale as a transportation fuel, according to Carter.
The blended fuel contains up to 15 percent ethanol, so it cannot be used with lawn and garden equipment.
“The issue with the lawn and garden industry is not the ethanol, it's when it sits,” Carter said. The tanks for those products aren't generally used every day like automotive tanks are.
“Is your material going to hold up through long haul? When you design and manufacture, you have to look at it for the long term,” he added. “There is a lot of uncertainty with E-15 and how it will go.”